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Family and Species Accounts

WATERFOWL

Family Anatidae

Of almost 30 waterfowl species observed regularly in the Sierra, most pass over during spring and fall migration and only about half of those breed in the region. Most members of this family frequent low-elevation marshes, ponds, and reservoirs, but a few visit Alpine lakes and turbulent streams of the high country.

Waterfowl are distinguished from other birds by their bills, which are blunt, somewhat flattened (except for mergansers), with a hard tip, or “nail.” All species are excellent swimmers and well adapted to aquatic living, with webbed feet, long necks for underwater feeding, and thick coats of down. The region’s ducks can be roughly divided into two groups based on foraging techniques and corresponding anatomy: dabbling ducks, which are generally agile on land and feed by tippingup in shallow water; and diving ducks, which generally feed by diving and swimming under water. Diver’s legs are positioned far back on their bodies to help them dive and swim but render them nearly helpless on land, requiring them to run across the water’s surface before taking flight.

Swans and geese usually mate for life, and males and females wear identical plumage. Ducks are sexually dimorphic, with males displaying bright, well-marked breeding plumages and using elaborate courtship displays to attract the more subtly patterned females. Most duck species undergo a postbreeding molt into “eclipse” plumage that leaves the males looking very similar to females for about two months. The timing of this molt usually corresponds to a flightless period when flight feathers are replaced. This is followed by a molt of body feathers that produces the typical bright male plumage in time for the winter courtship season.

Ducks typically mate for a single season, with males taking no part in incubating eggs or caring for young and abandoning their mates soon after the last egg is laid. Waterfowl eggs are white, buff, or greenish in color and lack spots or other patterns. Geese and swans usually lay about five eggs, while most ducks lay five to more than ten. Females of most waterfowl incubate eggs for 20 to 30 days, and the precocial young can walk, swim, and feed immediately after hatching; they can fly after five to seven weeks—sooner for ducks than for swans and geese. Ducks are also sexually dimorphic in voice, due to an asymmetrical enlargement of the male’s windpipe (the tracheal bulla). This causes them to emit low grunts and whistles rather than the louder, and perhaps more familiar, vocalizations of females. This diverse, cosmopolitan family includes about 145 living species and 4 recently extinct species. The family name was derived from L. anas, a duck.

Greater White-fronted Goose

Anser albifrons

ORIGIN OF NAMES “Greater” to distinguish it from the “Lesser” White-fronted Goose (A. erythropus), a native of Eurasia; “white-fronted” for the margin of white feathers surrounding their bills; L. anser, goose; L. albifrons, white forehead.

NATURAL HISTORY Some hunters call these birds “speckle-bellies” or “specs,” perhaps a more apt description than “White-fronted Goose.” The bold, horizontal barring on the bellies of adult birds is visible in flight, unlike its namesake white patch (“front”) at the base of the bill that can be seen only at close range. White-fronted Geese graze on grasses, fallen grain from harvested fields, and aquatic plants while on the wintering grounds. Winter flocks numbering in the tens of thousands roam rice fields and wetlands in search of abundant sources of food, where they mingle with white Snow and Ross’s Geese. White-fronts travel in V-shaped wedges high above the landscape, frequently uttering loud, laughing calls—somewhat reminiscent of high-pitched barking dogs; these double or multisyllabic calls are unlike those of other geese.

STATUS AND DISTRIBUTION Greater White-fronted Geese breed in the high Arctic regions of Alaska and northwestern Canada, and they winter abundantly in California and other southern states. They are among the first of the northern breeders to arrive in California, and wintering flocks can be seen by mid-September. They are also the last geese to depart in spring, and migrating flocks fly over river canyons in the northern Sierra until at least mid-April.

West Side. Uncommon spring and fall migrants, a few individuals land on large, reservoirs; individuals rarely seen in flocks of Canada Geese on Sierra golf courses and wet meadows.

East Side. From late February through early April, thousands congregate in Sierra Valley and Honey Lake prior to departing for northern breeding grounds; uncommon spring and fall migrants and overwintering birds recorded at most large lakes and reservoirs.

TRENDS AND CONSERVATION STATUS White-fronted Geese have made a dramatic comeback across North America, including wintering populations in California. The lowest populations were recorded in the 1970s, but reduced harvest levels implemented in the 1980s allowed their populations to increase dramatically by the mid-1990s. Christmas Bird Count data showed a tenfold statewide increase from lows of fewer than 10,000 in the early 1970s to more than 110,000 in 2010. Creation of wintering habitat has increased winter survival, and earlier snowmelt at northern breeding areas has resulted in increased breeding habitat.

Snow Goose

Chen caerulescens

ORIGIN OF NAMES “Snow” for the white plumage of adults; Gr. chen, goose; L. caerulescens, bluish, for the blue color morph of this species.

NATURAL HISTORY Thought to mate for life, Snow Geese remain in family groups and have strong family ties maintained for many years. The young do not breed until at least three years old, so family units can be quite large. Flock formations are not as organized as for other geese, and Snow Geese fly in loose wedges and long diagonal lines that may extend for miles. Among the most social of all waterfowl, Snow Geese often concentrate in huge flocks sometimes numbering more than 100,000 birds milling about in productive feeding areas. They fly up to 30 miles between feeding and roosting sites, and large flocks descending into a field can resemble falling snow. Wintering and migratory birds roost on water but forage mostly on land. Entirely vegetarian, they are drawn to recently harvested rice fields and grain stubble but also forage on bulrushes and other marsh plants in winter and on freshly sprouted grasses in spring. Once classified as a separate species, the rare (in California) “Blue Goose” is a dark color morph of the far more abundant Snow Goose and represents a tiny fraction of the species’ wintering population.

STATUS AND DISTRIBUTION Although they are abundant winter residents of the Central Valley, Snow Geese are only infrequent migrants over the Sierra in fall (early October to mid-November) and spring (mid-March to early April) that land occasionally on large lakes and reservoirs.

West Side. Uncommon spring, fall, and winter visitors to Lake Almanor but rare elsewhere; flocks sometimes numbering more than 500 birds cross the Sierra every year, primarily north of the Yosemite region.

East Side. Fairly common migrants through Sierra Valley and Honey Lake in spring and fall; rare or casual farther south.

TRENDS AND CONSERVATION STATUS Snow Goose populations in North America have quadrupled since the 1970s, possibly in response to increases in wintering carrying capacity created at refuges and in flooded rice fields. Their population explosion has impacted breeding habitat conditions throughout their range. Breeding birds are having major impacts on Arctic tundra environments by grubbing for roots and tubers disturbing the fragile soil and denuding large areas. Recently liberalized hunting seasons have been implemented to reduce populations to historic levels.

Ross’s Goose

Chen rossii

ORIGIN OF NAMES “Ross’s” for Bernard Rogan Ross (1827–1874), a trader for the Hudson’s Bay Company in the mid-1800s who collected many bird specimens, including this goose.

NATURAL HISTORY Smallest of our wintering geese, Ross’s Geese weigh only slightly more than Mallards but have much longer wingspans. They fly south from high Arctic breeding grounds in the company of Snow Geese, and the two species flock together in winter. In mixed flocks, Ross’s can be identified by their smaller size relative to the larger and more abundant Snows. Ross’s also have short, stubby bills and lack the “grin patches” of Snow Geese, and they seldom call in flight, unlike their larger cousins.

STATUS AND DISTRIBUTION Fall and spring migrants over the Sierra, Ross’s Geese might be spotted among flocks of Snow Geese on large lakes and reservoirs. “Blue-morph” Ross’s Geese can be found rarely in large flocks of “white” geese in the Central Valley but are accidental in the Sierra.

West Side. Rare spring, fall, and winter visitors at Lake Almanor and at other large reservoirs; casual south to Lake Isabella.

East Side. Uncommon in fall and winter in flocks of Snow Geese at Sierra Valley and Honey Lake; rare from Lake Tahoe south through the Owens Valley.

TRENDS AND CONSERVATION STATUS This species experienced a serious decline from the 1950s to 1970s, when its North American wintering population fell below 25,000 birds. However, full protection from hunting and the development of refuges and private wetlands have reversed this trend, and the wintering population in California now exceeds 100,000.

Cackling Goose

Branta hutchinsii

ORIGIN OF NAMES Branta, Modern English, related to “burnt” referring to the dark coloration of the head and neck; hutchinsii for Thomas Hutchins (1730–1789), an American frontiersman, surveyor, and geographer who collected the first specimen of a “small Canada goose” in northern Canada, where he was employed by the Hudson’s Bay Company.

NATURAL HISTORY Based on recent studies, the “Canada Goose complex” has been divided into two groups, including seven types of large-bodied Canada Geese (see account below) that mostly breed at lower latitudes and a group of five (one extinct) smaller forms known as Cackling Geese that breed in the high Arctic. Three forms of Cackling Geese visit California in winter, including “Aleutian” Cackling Goose (B. h. leucopareia), “Taverner’s” Cackling Goose (B. h. taverneri), and the form that once had exclusive use of the name, “Cackling” Cackling Goose (B. h. minima). The latter form is the one most likely observed with larger Canada Geese in the Sierra. Compared to Canada Geese, Cackling Geese are noticeably smaller, generally darker underneath, with shorter necks, smaller heads, and more delicate bills. The behavior and ecology of Cacklers and Canadas are similar and are covered in the following account.

STATUS AND DISTRIBUTION Cackling Geese are sometimes spotted in flocks of Canada Geese in fall, spring, and winter, but they leave for northern breeding grounds by late March.

West Side. Uncommon fall and winter visitors to the foothills below about 3,000 feet in the northern and central Sierra, and rare farther south; casual or accidental visitors to mountain lakes and meadows up to the Subalpine zone.

East Side. Rare; almost always seen in association with flocks of much more abundant Canada Geese.

TRENDS AND CONSERVATION STATUS “Aleutian” Cackling Goose populations dropped precipitously from the late 1960s to the mid-1980s, and this subspecies was listed as Endangered in 1967. The decline was due to a combination of predation from introduced Arctic foxes on their Aleutian Island breeding grounds, subsistence harvest in Alaska, and sport harvest on the wintering grounds, mainly in California. Careful management, including local control of foxes on the breeding islands and taking into account the need for fair and equitable bag limits among all hunters on the breeding and wintering grounds, promoted their rapid and encouraging recovery in recent decades. In 2001 the “Aleutian” Cackling Goose was removed from the Endangered Species list, and current populations are now well over 100,000 birds. The recent change in taxonomic status from a subspecies of Canada Goose to a full species has inspired birders to pay more attention to Cackling Geese, increasing reports and improving our knowledge of their status and distribution.

Canada Goose

Branta Canadensis

ORIGIN OF NAMES L. canadensis, of Canada, where a large portion of their population lives.

NATURAL HISTORY The loud honking of Canada Geese is often heard before their V-shaped flocks appear overhead. After forming pair bonds in their second or third winter, mated birds usually stay together for life, like other geese and swans. Extremely clannish, Canada Geese stay in family groups throughout the year. These strong social bonds led to the isolation of small breeding populations and the evolution of new subspecies across North America. Seven forms of “large-bodied” Canada Geese are currently recognized, with the most common form in the Sierra being large Great Basin “Honkers” (B. c. moffittii) that weigh up to 14 pounds. This is the only breeding subspecies in the Sierra, but other, smaller subspecies also mingle with Honkers in pastures, ponds, and golf courses in fall, winter, and spring. The smallest and darkest members of the “Canada Goose complex,” Cackling Geese (B. hutchinsii), are now recognized as a separate species (see account above).

Honkers nest commonly in the Great Basin and Sierra, and the breeding season usually extends from late February through mid-July. Monogamous pairs select nesting sites in a variety of natural and artificial sites, usually near water. Nesting pairs aggressively defend their territories, hissing menacingly if perceived predators (including humans) or neighboring geese venture too close to the nests. Artificial nesting structures are readily used, especially when located in farm ponds with irrigated pastures or golf courses nearby. They construct nests from local plant materials, usually cattails, tules, or small twigs. Nests are large, with outside diameters two feet or more, but the inner cup is only about nine inches and lined with soft down and plant fibers. Both parents care for the goslings and establish strong family ties that hold them together during migration and on the wintering grounds.

Primarily vegetarians, Canada Geese forage for grasses, clovers, and cultivated grains in pastures, wet meadows, and grain fields. More than most waterfowl, they have adapted their foraging behavior and migrations (or lack thereof) to exploit agricultural crops and other human-created food sources and habitats. Since Canada Geese are quick to use human-made habitats, they often multiply and become a nuisance in such settings because of their abundant droppings and aggressive behavior.

STATUS AND DISTRIBUTION Historically, most of California’s Canada Goose population nested farther north in the Cascades and the Great Basin and visited the Sierra in transit between their breeding and wintering grounds. In recent decades, however, creation of reservoirs, artificial ponds, golf courses, and irrigated pastures has expanded the habitat available for these adaptable geese, and they are now year-round residents in many areas.

West Side. Common or locally abundant residents throughout the western foothills north of the Yosemite region; uncommon or rare farther south; at higher elevations nesting occurs at Lake Almanor, Lake Van Norden (in Placer and Nevada Counties), and other large reservoirs.

East Side. Common to locally abundant residents in suitable habitats; representative nesting areas include Sierra Valley, Honey Lake, Lake Tahoe, Bridgeport Reservoir, Mono Lake, and Owens Valley.

TRENDS AND CONSERVATION STATUS Prior to the early 1970s, resident Canada Goose populations outside of northeastern California were small and localized to a few areas in California, including Butte County (the Oroville area) and some breeding birds in the Bay Area. Some of these may have been the progeny of birds released by the California Department of Fish and Game decades ago or from private breeders or hunting clubs. Once a few pairs become established in urban or suburban settings, where they cannot be hunted, they reproduce at remarkable rates and have done so all across the state and country. Sierra populations reflect this overall trend. Before the mid-1980s, Canada Geese were very rarely recorded on any Sierra Breeding Bird Survey routes. They are now routinely found on nearly a third of those routes, and they are now common breeders in suitable habitats on both sides of the Sierra.

Tundra Swan

Cygnus columbianus

ORIGIN OF NAMES “Tundra” for the species’ high Arctic breeding range; “swan” may be derived from an OE. word meaning “sound,” or possibly from L. sonus, a sound; L. cygnus, swan; L. columbianus, of the Columbia River, where the type specimen of the species was collected.

NATURAL HISTORY When sitting on the water with necks erect, Tundra Swans tower above nearby geese and ducks; adults weigh up to 16 pounds and have 7-foot wingspans. Mated pairs stay together for life, and their young become sexually mature after four years. Strong family ties keep related groups together on 5,000-mile round-trip journeys to and from high Arctic breeding grounds. They usually arrive in California by mid-October and depart by mid-March.

Due to their large body mass, swans must run across the water’s surface for a considerable distance before taking flight. Once aloft, their flight is rapid and direct, as V-shaped wedges cut through the sky. Like geese, swans have their legs positioned for good balance for walking and roosting in pastures and harvested grain fields. They are also powerful swimmers and forage in shallow water, wet fields, and irrigated pastures. Swans never dive but instead dip their heads and necks in shallow water and occasionally tip up. After a winter of frequent dipping into muddy or alkaline water, their heads may attain a rusty color. Preferred foods include leaves, stems, seeds, and tubers of aquatic plants as well as the seeds and young shoots of rice and other grain crops.

STATUS AND DISTRIBUTION Tundra Swans are mostly confined to rice-growing areas and wildlife refuges of the Central Valley and California’s northeastern plateau in late fall and winter. Tens of thousands congregate in rice fields north of Marysville, Yuba County, and in the low foothills along Highway 20 between Grass Valley and Marysville, just west of the Sierra.

West Side. Common spring, fall, and winter visitors to Lake Almanor; rare at other foothill reservoirs north of the Yosemite region; casual migrants south to Lake Isabella.

East Side. Uncommon or rare winter visitors to most large lakes and reservoirs; most records in late December or January.

TRENDS AND CONSERVATION STATUS For more than 60 years Tundra Swans have been protected from hunting in California, allowing their populations to recover dramatically from the early 20th century, when they were shot indiscriminately for their plumage. Meat of older birds was considered too tough for human consumption.

Wood Duck

Aix sponsa

ORIGIN OF NAMES Wood refers to the species’ preferred habitat; Gr. aix, waterfowl; L. sponsa, bride, a reference to the male’s elegant plumage.

NATURAL HISTORY The exquisite breeding plumage of male Wood Ducks reflects metallic patterns of green and violet when bathed in sunlight. They are the only North American waterfowl with entirely iridescent wings and backs, and males display more different colors than any other Sierra bird. Females are similar in shape but wear more subdued tones. Their relatively small size (about half the size of Mallards), long tails, and broad wings enable graceful flight through dense woodlands. When disturbed, females make loud, nasal shrieks, and the males give low, squeaky whistles.

As their name suggests, Wood Ducks are partial to forested backwaters, where oaks, willows, cottonwoods, or dogwoods form dense tangles over water. They search for oaks with abundant acorns, an especially favored food. Wood Ducks usually hunt for acorns and other seeds in leaf litter of the forest floor but also land in trees and pluck them from the highest branches. They also forage in water for aquatic plants, insects, and other foods. Wood Ducks usually forage by bobbing at the water surface like puddle ducks but will also make shallow dives for submerged prey.

Courtship behavior begins in midwinter, when females fly to high perches to summon prospective mates; they are unique among Sierra ducks in their ability to perch in trees. Often, several males will compete for a single female until she selects her favorite. Mated pairs show great affection and often preen each other gently on their heads and backs. Females invite copulation by submerging their bodies in shallow water with outstretched heads and necks, as their chosen mate circles nearby.

Cavities in large trees are the Wood Duck’s natural nesting sites. However, most pairs now use artificial nest boxes that have been installed widely in the Sierra foothills and throughout the state. Within a day of hatching, females coax their downy young from the nest. The tiny size and fluffy down of day-old hatchlings allow them to flutter uninjured to the ground from heights more than 50 feet and then walk away to the nearest wetland. Mothers alone guard their broods from predators—including raccoons, river otters, feral cats, opossums, large predatory fish (especially largemouth bass), and non-native bullfrogs—that may consume entire broods. The young are highly vulnerable to predators until they attain flight, which requires up to 70 days. After the breeding season, Wood Ducks do not require densely wooded areas and might be seen floating with other ducks on open lakes and reservoirs.

STATUS AND DISTRIBUTION Year-round residents of the Sierra foothills, Wood Ducks have expanded their distribution upslope in response to the creation of ponds and the placement of artificial nesting boxes.

West Side. Fairly common residents and nesters in bottomlands of all the major rivers from the Feather in the north to the Kern in the south; nesting pairs frequent wooded ponds and stream courses (including beaver ponds) up to about 4,000 feet in the central Sierra, where they remain through the winter even during heavy snow storms.

East Side. Uncommon visitors from spring through fall; nesting pairs at Sierra Valley and, at least historically, at south Lake Tahoe; rarely, nonbreeding visitors observed farther south, with records from Bridgeport Reservoir and Mono Basin in spring and fall; casual to accidental in winter.

TRENDS AND CONSERVATION STATUS Extensive clearing of flooded, bottomland forests eliminated Wood Duck habitat throughout North America. According to William Dawson (1923), their California and continental populations were on the verge of extinction by 1913: “Unceasing exposure to gun-fire has brought its ruin. And for what? Simply that the pot might be kept boiling, and the great American belly might be filled . . . Because its flesh was sapid, its bridal array was stripped from it and flung on the dump, while its quivering ounce of meat went into the pot. The lord of creation has dined—but where is the Wood Duck?”

Although excessive hunting pressure and habitat loss greatly reduced their populations in the early 1900s, they are now fairly common in suitable habitats throughout California. Focused efforts by the California Department of Fish and Game, U.S. Fish and Wildlife Service, California Waterfowl Association, and Ducks Unlimited have greatly increased local populations statewide, including in the Sierra foothills. Data from Sierra Christmas Bird Count Circles and Breeding Bird Survey routes show a stunning increase, with numbers up nearly five-fold since the early 1980s. American Kestrels, European Starlings, Northern Flickers, small owls, honey bees, and wasps may compete with Wood Ducks for these artificial homes.

Gadwall

Anas strepera

ORIGIN OF NAMES Gadwall is a name of unknown origin; L. anas (see family account above); L. strepera, noisy, for the loud calls—similar to a female Mallard’s.

NATURAL HISTORY Compared to other puddle ducks, Gadwalls wear subtle plumage and lack the bright, iridescent hues that characterize this group. In most places these shy ducks are outnumbered by other species, but they have one of the widest distributions of any of the world’s waterfowl and occur on all continents except South America, Australia, and Antarctica.

Gadwalls are primarily freshwater birds but also visit saline and alkaline waters—even in the breeding season. They nest on dry ground near ponds and marshes surrounded by lush aquatic vegetation such as cattails and bulrushes; islands are preferred nest sites. Monogamous during the breeding season, most females are paired by November, many months before they nest in mid-April. Nests consist of shallow depressions lined with aquatic vegetation, feathers, and down. After breeding, Gadwalls roost and forage on large marshes, lakes, and reservoirs in mixed flocks with other puddle ducks and American Coots. They usually forage in deeper water than other puddle ducks, where they upend or make shallow dives for aquatic plants, seeds, and aquatic invertebrates.

STATUS AND DISTRIBUTION Gadwalls are year-round residents and migrants in California, including both sides of the Sierra.

West Side. Uncommon breeders below about 3,000 feet in the central Sierra; confirmed nesting locations include Lake Almanor, Don Pedro Lake (Tuolumne County), Millerton Lake (Madera and Fresno Counties), Lake Success, and Lake Isabella; rare in fall up to about 8,000 feet in Yosemite National Park.

East Side. Common nesters at marshes and creek deltas; in fall, large numbers congregate on large lakes and reservoirs; fairly common in winter.

Eurasian Wigeon

Anas Penelope

ORIGIN OF NAMES “Eurasian” refers to the typical distribution of the species; “wigeon” from F. vigeon, a whistling duck; Gr. penelope, a weaver; possibly a mistaken form of penelops, duck.

NATURAL HISTORY The bright reddish heads, cream-colored crowns, and silvery flanks of male Eurasian Wigeon stand out in large flocks of wintering waterfowl. Females, however, look nearly identical to female American Wigeon. While Eurasian Wigeon do not breed in North America, some Russian Far East breeders follow flocks of the far more abundant American’s on their southward journeys. Larger wintering flocks of American Wigeon (i.e., 50 to 100 birds) may contain at least one Eurasian Wigeon. The wintering behavior and ecology of Eurasian and American Wigeon are nearly identical.

STATUS AND DISTRIBUTION Eurasian Wigeon are one of the most abundant and widespread ducks in Asia and Europe and uncommon winter visitors to California.

West Side. Uncommon to rare November through March, mostly on ponds and lakes in the Foothill zone; recent winter and early spring records from large reservoirs such as Lake Almanor and Lake Isabella; has been nearly annual recently on the Springville Christmas Bird Count (Tulare County).

East Side. Uncommon to rare at large marshes and reservoirs in late fall, winter, and early spring.

American Wigeon

Anas Americana

ORIGIN OF NAMES “American” to distinguish the species from Eurasian Wigeon; L. americana, of America

NATURAL HISTORY Most American Wigeon breed in the prairies and tundra of Canada and Alaska, but they also nest in small numbers in the Great Basin, north and east of the Sierra. Migrants arrive by mid-November to spend the winter in California. Mostly vegetarian, they feed at the surface for such aquatic plants as pondweeds, wild celery, and algae. At times, they associate with divers, such as Lesser Scaup, Canvasbacks, and Redheads, and steal aquatic vegetation after these ducks surface from dives. Wigeon are drawn to wet pastures, urban parks, and golf courses, where they graze on grasses, usually not in association with domestic ducks or geese. In winter, they consume primarily aquatic and terrestrial insects and small mollusks. On hunting days in the Central Valley, American Wigeon and other dabbling ducks sometimes flock to protected ponds and wetlands of the western foothills to escape hunting pressure.

STATUS AND DISTRIBUTION Abundant winter visitors to the Central Valley and coastal California, American Wigeon occur regularly on both sides of the Sierra.

West Side. Fairly common to locally abundant fall, spring, and winter visitors to larger reservoirs such as Lake Isabella, Lake Almanor, and Millerton Lake, and fairly common visitors to ponds and lakes in the Foothill zone; in fall, rare or casual at higher elevations.

East Side. Fairly common in winter and common in spring and fall migration at marshlands, ponds, and slow-moving creeks, with especially large numbers concentrating at Sierra Valley, Honey Lake, Bridgeport Reservoir; breeds on rare occasions in Mono County (most recently at Crowley Lake in 2007).

Mallard

Anas platyrhynchos

ORIGIN OF NAMES Mallard was apparently derived from L. masculus, male, referring to the drakes; platyrhynchos, flat-billed, from Gr. platus, flat, and rhynchos, a bill.

NATURAL HISTORY Mallards are the most abundant, widely distributed, and best known ducks in the Northern Hemisphere. Bred in captivity since ancient times, they are the ancestors of most domestic breeds, including white “Peking” ducks as well as other barnyard ducks, save for a few breeds that are derived from unrelated Muscovy Ducks that occur in the wild from South Texas to South America.

Highly promiscuous, male Mallards try to mate with as many females as possible—often very aggressively with several males chasing and trying to copulate with a single female on land or while pushing her under water until she nearly drowns, called “rape attacks” by some. Although wild Mallards rarely mate with other species, captive birds have produced fertile offspring with more than 40 different species of ducks and geese. Domestic flocks of ducks in urban parks and barnyards often feature the odd-looking progeny of such mixed-matings.

In flight, Mallards have large, broad bodies and slower wingbeats than most other ducks. They walk proficiently on land and fly directly up from the water when flushed. They mostly feed in shallow water by tipping-up but also make shallow dives for food, unlike most puddle ducks. They primarily consume submerged aquatic plants such as pondweeds, smartweed, and bulrush. In summer they also take animal foods, including the larvae and nymphs of mayflies, stoneflies, and midges.

These hardy and adaptable ducks will nest almost anywhere adequate food supplies exist. Similar to Canada Geese, they adapt rapidly to artificial habitats and are frequent visitors to ponds at farms, golf courses, and urban parks. They hide their ground nests under tall grasses or dense marsh vegetation. Females care for their young for about two months until they are capable of flight.

STATUS AND DISTRIBUTION Mallards are the most abundant ducks in the Sierra, and their distribution has expanded during the past decades with the creation of ponds, reservoirs, and other artificial wetlands, allowing them to colonize almost anywhere.

West Side. Common nesters up to about 4,000 feet in the central Sierra; uncommon at higher elevations, a few pairs nest annually up to the Subalpine zone above 8,000 feet in the central Sierra; in late summer and fall, small flocks of migrants found at all elevations.

East Side. Common nesters and fairly common year-round residents in suitable marsh and lake habitats.

TRENDS AND CONSERVATION STATUS Data from Sierra Breeding Bird Survey routes show a steady increase in numbers and expansion of breeding range throughout the region since the 1970s.

Cinnamon Teal

Anas cyanoptera

ORIGIN OF NAMES “Cinnamon” refers to the body coloration of males in breeding plumage; cyanoptera, blue-winged, from Gr. chyaneous, blue, and pteron, wing.

NATURAL HISTORY In low light conditions, male Cinnamon Teal appear as small, all-dark ducks, but full sunlight transforms them into birds of breathtaking beauty. As they wheel low over a marsh with rapid, twisting flight, both males and females reveal baby-blue wing patches. Cinnamon Teal perform courtship and form seasonal pair-bonds on their southern wintering grounds, prior to migrating northward to breed. After arriving on their breeding grounds, pairs search for nest sites in wetland habitats; both small ponds and large marshlands are used. Females tunnel under dense, matted marsh plants and create shallow scrapes for nests that are lined by soft grasses and down. Both parents may tend the young until they can fly after about seven weeks.

In the nonbreeding season, these bright-colored ducks occur in small flocks, often in association with other puddle ducks or American Coots. Cinnamon Teal forage primarily at the edges of ponds and sloughs for bulrushes, pondweed, and sedges. They also consume a limited amount of animal food when breeding, mostly bugs, beetles, and snails.

STATUS AND DISTRIBUTION Unlike most puddle ducks, Cinnamon Teal winter primarily in Mexico and fly north to breeding grounds in fresh and brackish marshes in the western United States and southern Canada.

West Side. Uncommon nesters at ponds, reservoirs, and marshes of the lower foothills, spring migrants arrive by early March and remain through mid-September; nesting confirmed at Lake Isabella and Lake Almanor; rare in winter in Kern River Valley and southern foothills; rare visitors above 3,000 feet in the central Sierra during spring and fall migration.

East Side. Common nesters in marshlands from Honey Lake south into the Owens Valley; rare or casual in winter.

Northern Shoveler

Anas clypeata

ORIGIN OF NAMES “Shoveler” refers to the species’ shovel-shaped bill; L. clypeum, shield, another reference to bill shape.

NATURAL HISTORY Called “Spoonies” by hunters, Northern Shovelers have large, flattened bills that resemble spoons. These specialized bills have comb-like teeth (called “lamellae”) on the mandibles, through which food is strained from shallow water or mud. They primarily feed in shallow water, where aquatic prey float near the surface; unlike most other puddle ducks, they never forage on land. Shovelers are highly carnivorous and primarily consume crustaceans, snails, tadpoles, caddisflies, damselflies, and the nymphs and larvae of other aquatic insects. They also use their shovel-like bills to scoop up organic material from muddy pond bottoms. Their highly sensitive tongues make it easy to accept or reject potential food items. Shovelers tend to be monogamous and mated pairs can stay together for several years or more.

Shovelers occur in a variety of wetland habitats ranging from small ponds to large reservoirs and are especially fond of sewage treatment ponds. The primary requirement appears to be the presence of large quantities of invertebrate animal food. They congregate on large bodies of open water for roosting to avoid predators. They prefer ice-free lakes that provide access to pond bottoms, and for this reason they are among the first waterfowl to depart their breeding grounds in Alaska and Canada in late summer.

STATUS AND DISTRIBUTION Northern Shovelers begin to arrive in California by late August, and most depart for northern breeding grounds by early May.

West Side. Uncommon visitors to the lower foothills, migrants observed to above 3,000 feet in the central Sierra; possible nesting at Lake Isabella and Lake Almanor.

East Side. Uncommon but becoming more regular in winter; common during spring and fall migrations at large wetlands, including Sierra Valley, Bridgeport Reservoir, Mono Lake, and Crowley Lake; possible nesters in Sierra Valley.

TRENDS AND CONSERVATION STATUS In the fall of 1948, almost a million Northern Shovelers were recorded at Mono Lake, demonstrating this was once a major staging area for the species in the eastern Sierra. However, after more than 50 years of water diversions from its major tributary streams, Mono Lake’s surface area dropped and the lake became too alkaline and salty for most puddle ducks, including shovelers. With the return of freshwater flows to the lake since the mid- 1990s, waterfowl are starting to return to the lake, and hundreds of shovelers can now be seen, especially near the springs and creek deltas along the eastern lakeshore. North American breeding populations appear to be stable to increasing. Christmas Bird Counts on both sides are recording higher numbers since the early 1990s.

Northern Pintail

Anas acuta

ORIGIN OF NAMES “Pintail” refers to the species’ long, pointed tail feathers; L. acuta, pointed.

NATURAL HISTORY Among the most stylish waterfowl, male Northern Pintails are large, elegant ducks. Like other puddle ducks, they are primarily surface feeders that dabble in shallow water. Pintails mostly consume vegetable matter such as pondweeds, sedges, and grasses. They are drawn to agricultural crops, especially flooded rice fields where waste grain is abundant. Organic rice fields, especially those with wild rice are preferred. In summer they consume small fish, frogs, mollusks, and the larvae and nymphs of aquatic insects.

Northern Pintails have a wider global distribution than any duck, and breed or winter on all continents except for Australia and Antarctica. A few Northern Pintails nest in the Sierra, but most of their population migrates north or east to breed. They are among the first migrant waterfowl to arrive in California, usually by mid-September; many continue south to winter in Mexico, Central America, or northwestern South America. Pintails nest in open, wetland habitats with low emergent vegetation such as cattails and tules. Nesting sites are usually on islands or small berms surrounded by water. The nest is a small scrape or depression lined with plant material, feathers, and down.

STATUS AND DISTRIBUTION Abundant winter visitors to the Central Valley and coastal California, Northern Pintails occur regularly on both sides of the Sierra but rarely in large numbers.

West Side. Uncommon fall, winter, and spring visitors to ponds and reservoirs of the foothills up to about 3,000 feet in the central Sierra; possible nesters have been observed at Lake Almanor and Lake Isabella.

East Side. Fairly common spring and fall migrants; a few pairs nest annually in marshes of Honey Lake, Sierra Valley, and Crowley Lake; winter status is variable, with few to none some winters and many in others.

TRENDS AND CONSERVATION STATUS In contrast to most species of waterfowl, Northern Pintails have shown generally negative population trends in recent decades. Data from California Christmas Bird Counts show that winter numbers are down significantly. Data from Sierra Christmas Bird Counts are insufficient to determine trends, but most circles are reporting smaller numbers than those seen in the 1970s and 1980s.

Green-winged Teal

Anas crecca

ORIGIN OF NAMES “Green-winged” refers to the bright wing patches of males and females; crecca, possibly a Latinized word to describe the species cricketlike calls.

NATURAL HISTORY Green-winged Teal are the smallest North American dabbling ducks and weigh less than a third of Mallards. These tiny ducks tend to stay at pond margins and in dense vegetation, sometimes making them hard to see. Like other teal, they have a rapid turning flight, low over water. Nesting sites are in sedge meadows or grasslands near ponds or other sources of permanent water. Females excavate small bowls lined with soft plant material, feathers, and down hidden in dense vegetation surrounded by water. Primarily vegetarians, they forage in shallow water by wading or swimming. Preferred foods are seeds of aquatic plants such as bulrushes, sedges, wild rice, smartweed, and wild millet. In summer they consume mostly animal foods such as beetles, bugs, and dragonfly and damselfly nymphs.

STATUS AND DISTRIBUTION Most of the Green-wing Teal wintering population migrates north and east to breed, but a few remain to nest and stay in California through the summer.

West Side. Uncommon visitors to marshes, ponds, and reservoirs of the foothills in fall, winter, and spring; possible breeding at Lake Almanor, and confirmed breeding at Lake Isabella.

East Side. Common spring and fall migrants to lakes and reservoirs, where they congregate in large flocks in fall and winter; uncommon breeders throughout the region.

Canvasback

Aythya valisineria

ORIGIN OF NAMES “Canvasback” for the whitish backs of breeding males; Gr. aythya, a water bird; Gr. valisineria, named for a genus of water celery (Vallisneria), a preferred food of the species.

NATURAL HISTORY Unlike most wide-ranging waterfowl, Canvasbacks are entirely restricted to North America. With whitish backs and sides, males stand out among other ducks on the water or in flight. One of the fastest waterfowl, they can attain flight speeds greater than 70 miles per hour. After running across water to become airborne, they fly in V-shaped flocks powered by direct, rapid wingbeats, often at high altitudes. They are also accomplished divers, capable of frequent, sustained dives in water up to 30-feet deep. However, they usually forage in water 10 feet deep, or less, where they search for preferred foods including clams, snails, fish, tadpoles, and wild celery.

While most Canvasbacks breed in the northern prairies and tundra, a portion of their population nests in marshes of the Great Basin, including the northeastern Sierra. Preferred nesting areas are dense freshwater marshes, where females conceal bulky nest platforms of marsh plants under tall emergent plants such as cattails and tules, over or adjacent to water.

STATUS AND DISTRIBUTION Primarily winter visitors to California, Canvasbacks are common in coastal waters and inland on large, open water bodies.

West Side. Rare winter visitors to foothill lakes and reservoirs but significant numbers sometimes found at Lake Almanor; no breeding records.

East Side. Uncommon spring and fall migrants and summer residents; usually scarce in winter but occasionally present in double-digit numbers on Honey Lake or South Lake Tahoe Christmas Bird Counts; rare breeders, with nesting confirmed only in Sierra Valley.

TRENDS AND CONSERVATION STATUS Canvasback populations have declined from their historical abundance across North America in response to changes in land use, loss of wetlands, and hunting pressure. Prized by hunters, the flesh of birds that have consumed wild celery or other aquatic plants (instead of animal foods) is highly sought after. Canvasback populations have remained fairly stable in recent decades (higher numbers in wet years) in response to wetland protection and restoration on their breeding grounds and the enforcement of hunting limits. Numbers from Central Valley Christmas Bird Counts show a significant positive trend since the 1970s.

Redhead

Aythya Americana

ORIGIN OF NAMES “Redhead” refers to the head color of breeding males; L. americana, of America.

NATURAL HISTORY Female Redheads are considered nest parasites because they often lay their eggs in the nests of other ducks—especially those of other Redheads, Canvasbacks, and some puddle ducks. However, some females lay eggs only in their own nests or are partially parasitic. Because of parasitism, their clutch size is difficult to determine but probably averages about 9 eggs; “dump” nests may have more than 40 eggs laid by several different hens. Reproductive success is generally low in this species, resulting from a variety of causes including interference and desertion by parasitic hens, flooding or drying of active nests, and predation by mammals and predatory birds.

Redheads prefer to nest in fresh emergent wetlands where dense stands of cattails and tules are interspersed with areas of open water. For nesting habitat, they select relatively deep wetlands (three feet or deeper) of at least one acre, with about 75 percent open water and vegetation up to about three feet in height. They also nest in somewhat alkaline marshes and potholes of the interior. Nests are built from marsh plants and secured to tall emergent vegetation; they are usually over water but occasionally on islands or dry ground.

In winter and migration, Redheads forage and rest on large, deep bodies of water and may form rafts far from shore. Food is taken mostly by diving in deep water, but they also forage in shallow water. Unlike most diving ducks that prefer animal foods, Redheads consume mostly submergent, aquatic plants such as pond weeds, wigeon grass, and duckweed, but they also take aquatic insects, grasshoppers, larvae of midges and caddisflies, small clams, and snails.

STATUS AND DISTRIBUTION Redheads are year-round residents in California, but the small breeding population is supplemented by northern migrants in fall and winter. They winter primarily along the coast and at large, inland water bodies.

West Side. Rare or uncommon spring and fall migrants and winter visitors; breeding suspected at Lake Almanor but has been confirmed only at the Kern River Preserve (i.e., Prince’s Pond) near Lake Isabella.

East Side. Fairly common spring and fall migrants and summer residents, especially in wet years when freshwater marshes provide large areas of suitable habitat; occasionally present in fair numbers in winter on lakes and reservoirs; breeding documented at Honey Lake Wildlife Area, Sierra Valley, Mono Basin, Crowley Lake, and other Mono County sites.

TRENDS AND CONSERVATION STATUS Once considered the most abundant diving ducks in California, the state’s breeding and wintering Redhead population has been greatly reduced since the early 1900s, primarily due to the loss of permanent wetlands throughout the Central Valley and historical hunting pressure. Called “fool ducks” by some hunters, they are easy to decoy and hunt compared to most other waterfowl. Based on declines in the Redhead’s overall population size and range, and continuing threats (e.g., ongoing wetland losses, nesting failures, and historical and possibly recent hunting pressure), the state’s breeding population was added to the California’s list of Bird Species of Special Concern in 2008.

Ring-necked Duck

Aythya collaris

ORIGIN OF NAMES “Ring-necked” for the chestnut-colored neck bands of breeding males; L. collaris, collared.

NATURAL HISTORY Despite their name, male Ring-necked Ducks have chestnut collars so faint they are difficult to see even at close range. From a distance their dark heads and backs, vertical white stripes on the leading edge of the flanks, and white ring around the bill tip make much better field marks—they might be more properly named “Ring-billed Ducks.”

Ring-necks tend to flock with members of their own kind on farm ponds and reservoirs; they almost never occur on salt water. Like most divers, they must run across the water surface for a considerable distance before taking flight. Wintering flocks frequent large, open bodies of water. In contrast, nesting pairs select smaller, secluded lakes and ponds—often surrounded by forest. Females build nests of grasses and aquatic plants, usually near or over water. Primarily vegetarians, their main foods include pondweeds, smartweeds, and occasionally insect larvae.

STATUS AND DISTRIBUTION Ring-necked Ducks are visitors and migrants to California, including both sides of the Sierra.

West Side. Fairly common fall and winter visitors to low-elevation lakes, ponds, and reservoirs the length of the West Side; rare nesters with breeding only documented at Buck’s Lake but probably breeds at other deep lakes of the northern Sierra; pairs in suitable Sierra breeding habitats have been seen in midsummer as far south as Madera County south of Yosemite National Park, suggesting a recent southward-range extension.

East Side. Uncommon fall visitors to larger lakes and reservoirs; hens with broods at secluded lakes in the Tahoe Basin, Meiss Lake (Alpine County), and at Crowley Lake.

Lesser Scaup

Aythya affinis

ORIGIN OF NAMES “Scaup” was modified from OE. scalp, shellfish, a food of this species; L. affinis, allied with or related to, refers to close relationship to the larger Greater Scaup (A. marila), a rare species in the Sierra (see Appendices 1 and 2).

NATURAL HISTORY As their name suggests, Lesser Scaup are slightly smaller than their close relatives, Greater Scaup. The two species are often lumped together by hunters who call them “blue-bills,” or “bluies,” instead of scaup.

Lesser Scaup are restricted to the Western Hemisphere, where they breed in subarctic wetlands of Alaska and Canada and winter as far south as northern South America. While they also occur in coastal waters, Lesser Scaup are much more numerous in California’s interior than Greater Scaup. In winter they primarily consume animal foods including crustaceans, mollusks, and aquatic insects obtained by diving. Lesser Scaup tend to feed in shallower water than some other divers, usually about 5 or 6 feet deep, but sometimes they dive up to 20 feet.

STATUS AND DISTRIBUTION Lesser Scaup are winter visitors and spring and fall migrants to California, and there are no breeding records for the Sierra region.

West Side. Uncommon visitors to most large foothill lakes and reservoirs up to about 3,000 feet in the central Sierra.

East Side. Uncommon visitors to most large lakes and reservoirs, annual records from Honey Lake, Sierra Valley, Lake Tahoe, Topaz Lake, Mono Lake, and Crowley Lake.

Harlequin Duck

Histrionicus histrionicus

ORIGIN OF NAMES “Harlequin” for this species’ multicolored plumage, reminiscent of the brightly colored characters of the pantomime stage; L. histrionicus, related to L. histro, actor.

NATURAL HISTORY Nesting Harlequin Ducks prosper amid swirling torrents and rapids of mountain streams. According to William Dawson (1923): “A baby Harlequin is as thoroughly at home in wild waters as a baby trout. The trout we may seduce with worm or fly, but until we have devised an equally interesting method for attracting young Harlequins, our meetings are likely to be infrequent.” As Dawson implied, Harlequins were considered rare in the state by the early 1920s.

In the late 1870s, Lyman Belding (1891) reported: “I have noticed many of these ducks on the principal streams of Calaveras and Stanislaus counties in the summer. . . . I find young broods from about 4000 feet upward, the earliest apparently hatched about the first of June, or earlier, and have often surprised the mother ducks with their broods hidden in Saxifrage . . . when I approached within a few feet of the brood . . . all would hurriedly swim from me, vigorously using both feet and wings to propel themselves against or with the rapid currents.” While no nests of these hardy ducks have been described in California, Harlequins elsewhere nest on the ground, under the shelter of driftwood or rocks, and always beside swift, flowing rivers. They sometimes nest on cliff ledges and in cavities in trees and stumps lined with conifer needles, mosses, or leaf litter. Nest building begins from early May to early June, and they only produce one brood per year. Females care for their precocial young alone, when they often move to slower stretches of nesting streams.

Harlequins are adept underwater swimmers, and they seek clear, cold rapids, where they search rock crevices for aquatic insects including the adults, nymphs, and larvae of caddisflies, mayflies, and stoneflies. They use their huge feet to navigate the bottoms of rushing steams over wet, polished stones—much like American Dippers, which share their summer haunts and their favored prey.

STATUS AND DISTRIBUTION Most Harlequins currently wintering along the California coast are from northern breeding populations, but a few pairs probably nest along remote rivers of the Sierra each year in greatly reduced numbers from their historical population.

West Side. Rare, all historical records from turbulent headwaters from the Stanislaus River south to the upper San Joaquin River and specific nesting localities included Griswold Creek (tributary to the Stanislaus River), South Fork of the Tuolumne River, Cherry Creek (tributary to the Tuolumne River), South Fork Merced River, Lake Ediza (9,300 feet, near the headwaters of the San Joaquin River), and the South Fork Merced River in Yosemite Valley; also observed along the South Fork Kaweah and the South Fork Kings Rivers, but nesting there was not confirmed. Currently rare, casual, or absent from most of the historical breeding range in the Sierra; confirmed breeding records since the early 1970s include above Salt Springs Reservoir on the Mokelumne River, on the Feather River near Thermalito Forebay, and, most recently, on the Merced River in Yosemite National Park in 2002; recent breeding season observations of Harlequins (breeding status not confirmed) include North Fork Feather River, North Fork American River, Rubicon River, Silver Fork of the South Fork American River, North Fork Mokelumne River, Tenaya Creek and the South Fork Merced River in Yosemite National Park, the upper San Joaquin River, and below Friant Dam on the lower San Joaquin River.

East Side. No historical or recent records.

TRENDS AND CONSERVATION STATUS Harlequin Duck was added to California’s list of Species of Special Concern in 2008. Despite its rarity and declining status, this species has not been listed as either Threatened or Endangered—mostly because it is seen so infrequently and so little is known about its recent breeding status in the Sierra. The exact cause of the Harlequin’s decline is unknown. Increased disturbance from human recreational activities and damming of historical nesting streams have also reduced the suitability of many Sierra rivers for nesting Harlequins. Historical gold mining had severe but unmeasured effects on their riverine habitats and breeding populations.

Bufflehead

Bucephala albeola

ORIGIN OF NAMES “Bufflehead” derives from Fr. buffle, buffalo, referring to this species’ large head; bucephala from Gr. bous, ox or bull, and kephale, head; L. albus, white.

NATURAL HISTORY The rounded heads of these dapper little ducks reminded early ornithologists of a buffalo’s profile, hence the name Bufflehead. At a distance males look black and white, but close views reveal a bright purple and green iridescence on their heads. They sit buoyantly high on the water and can fly up directly from the surface rather than having to skitter across the water to gain speed like most diving ducks. Buffleheads fly rapidly, flashing white patches on their whirring wings. Much like their close relatives, the Goldeneyes, they dive for small fishes or search the bottom oozes for shellfish, aquatic insects, and other prey; less commonly they feed at the surface like puddle ducks.

Most of California’s Bufflehead population breeds in forested mountain lakes of the Cascades and farther north, but recently they have been confirmed nesting in the Sierra. In April, drakes begin to actively court females and threaten other males by swimming at them with heads lowered and wings flapping. Unlike most ducks, Bufflehead pairs usually remain together for years. Their preferred breeding habitats are small ponds lined by conifers or aspens. Similar to Wood Ducks, they nest in tree cavities, usually larger ones excavated by Northern Flickers or Pileated Woodpeckers. Other cavity-nesting birds such as Western Bluebirds and European Starlings are considered competitors for suitable nest sites. Breeding activities begin in early May, and peak nesting extends from mid-May until late July. Females line their nest holes with down and feathers before laying eggs; the young remain in the nest for about a day before jumping to the ground and joining the hen on the nearest water and become independent after about 50 days.

STATUS AND DISTRIBUTION Similar to Ring-necked Ducks and Hooded Mergansers, Buffleheads are primarily boreal ducks that have recently extended their breeding range southward into the Sierra.

West Side. Uncommon breeders; prior to the mid-1990s, Sierra nesting confirmed only at Lake Almanor and near Buck’s Lake; recent observations have confirmed localized nesting at secluded, tree-lined lakes in Sierra, El Dorado, Placer, and Alpine Counties—most of these localities are above 6,500 feet; fairly common winter visitors and spring and fall migrants to deeper reservoirs, lakes, and ponds, mostly in the foothills below about 3,000 feet in the central Sierra.

East Side. Recent breeding confirmed in Sierra, El Dorado, Alpine, and Inyo Counties; fairly common spring and fall migrants and winter visitors to larger lakes and reservoirs.

Common Goldeneye

Bucephala clangula

ORIGIN OF NAMES “Goldeneye” for the species’ bright golden eyes; clangula, the diminutive form of L. clangor, noise, a reference to the whistling sounds of the species’ rapid wingbeats.

NATURAL HISTORY Common Goldeneyes were once called “Whistle-wings” or “Whistlers” for the distinctive whistling or squeaking sounds made by their wings in flight. They breed at boreal lakes and marshes throughout the Northern Hemisphere. In winter, they can be found along the coast and in all but the desert regions of the United States, where they frequent large bodies of water. Migratory flocks consisting mostly of juveniles begin to arrive in California by mid-October, but the bulk of their population remains on the breeding grounds until freezing conditions force them southward. While they form large rafts along with other diving ducks in deep water, Common Goldeneyes usually forage near shorelines in water less than 12 feet deep. Preferred foods include mollusks, crustaceans, aquatic insects, seeds, and tubers of aquatic plants. On Sierra lakes and rivers, they sometimes associate with Common Mergansers.

STATUS AND DISTRIBUTION Common Goldeneyes winter at higher elevations of the Sierra than most other diving ducks, except for Common Mergansers and Mallards; there are no breeding records.

West Side. Fairly common winter visitors and spring and fall migrants to most large lakes and reservoirs, as well as slow-moving stretches of major rivers from the low foothills to the Upper Conifer zone.

East Side. Fairly common visitors from November through March from Sierra Valley south; more common in recent decades than in the past.

Barrow’s Goldeneye

Bucephala islandica

ORIGIN OF NAMES “Barrow’s” for Sir John Barrow (1764–1848), an Englishman who promoted Arctic exploration; L. islandica, of Iceland, one of the species’ breeding areas.

NATURAL HISTORY In the Sierra, Barrow’s Goldeneyes are usually found in association with their much more numerous relatives, Common Goldeneyes, on large, deep lakes and rivers. Barrow’s Goldeneyes probably have always been rare nesters in California, as most of their population breeds at secluded lakes of the Cascades, Rockies, and mountainous portions of Alaska and Canada. Similar to Buffleheads and Wood Ducks, Barrow’s Goldeneyes nest in tree cavities such as abandoned woodpecker holes. Birdwatchers in the Sierra should be alert for these strikingly beautiful birds when scanning flocks of Common Goldeneyes.

STATUS AND DISTRIBUTION Historically at least, Barrow’s Goldeneyes were observed breeding in the Sierra, but there are no recent nesting records, despite extensive systematic and incidental surveys in formerly documented nesting areas.

West Side. Uncommon, before the 1940s a few nesting records from the Lassen region south to Fresno County, mostly from high-elevation lakes bordered by forests providing tree cavities for nesting; currently uncommon but regular in winter at Lake Almanor, on the Feather River at the De Sabla Reservoir, and at a few forested lakes and rivers of the central Sierra up to the Lower Conifer zone, with records from the Sonora and Valley Springs wastewater treatment ponds and Moccasin Reservoir (Tuolumne County); casual at higher elevations and south of the Yosemite region.

East Side. Fairly common along the Truckee River west of Reno and at the Truckee gravel ponds (Nevada County), with several birds present every winter; casual in fall and winter at Sierra Valley, and Lake Tahoe, but accidental farther south; careful searching of large goldeneye flocks on larger rivers, lakes, and reservoirs could reveal more records of this species.

Hooded Merganser

Lophodytes cucullatus

ORIGIN OF NAMES “Hooded” refers to the species’ distinctive, crested head; L. merganser, “a diving goose”; lophodytes from Gr. lophion, crest, and dytes, a diver; cucullatus from L. cucullata, a crest.

NATURAL HISTORY Of the three species of mergansers that occur annually in the Sierra, only Hooded Mergansers are restricted to North America, as Common and Red-breasted Mergansers also occur in Europe and Asia. Hooded Mergansers are the smallest and most dramatically colored of the three. At a distance, males might be confused with Buffleheads but their sides are tan, instead of white, and their delicate bills are long and pointed. Unlike the other mergansers that consume primarily fish, Hooded Mergansers also dine extensively on crayfish, amphibians, and aquatic insects—dragonfly nymphs are especially preferred. Their habitat preferences also differ from the other mergansers since they avoid the large lakes and rivers frequented by Commons and salt water preferred by Red-breasted Mergansers. Instead, Hoodeds in the Sierra seek secluded ponds and lakes in winter. Seldom pursued by hunters due to their fishy-tasting flesh, they are still wary ducks that dive or swim for cover when humans approach.

Most of the Hooded Merganser’s western population breeds along the Pacific Coast from southeastern Alaska south to Oregon. Historically they were not considered a breeding species in California, but they have expanded their range southward into the state in recent decades. Hooded Mergansers nest in tree cavities and make use of old woodpecker holes as well as artificial nesting boxes that have been installed widely in California for Wood Ducks—most of the state’s recent nesting attempts have been in boxes.

STATUS AND DISTRIBUTION Grinnell and Miller (1944) described the Hooded Merganser’s status in California as: “Winter visitant, relatively rare . . . never within history appreciably more numerous than now.” Since the mid-1960s, however, more than 100 Hooded Merganser nesting attempts have been documented in at least 20 California counties (Pandolfino et al. 2006). The number of wintering birds in the state has also increased in recent decades.

West Side. Fairly common and widespread winter visitors and spring and fall migrants to wooded lakes and ponds of the foothills regularly up to about 4,000 feet in the central Sierra; most recent nesting records from Plumas, Sierra, and El Dorado Counties, rare or casual south of the Yosemite region.

East Side. Common winter visitors to the Tahoe region, where they are regularly observed Lake Tahoe, Donner Lake, Glenshire Pond (Nevada County), the Truckee River west of Reno; otherwise uncommon migrants and rare in winter; no breeding records.

TRENDS AND CONSERVATION STATUS As noted above, the breeding range of this species has expanded into northern California in recent years. Data from California Christmas Bird Counts show a dramatic increase in the winter population as well. Sierra counts show an even greater positive trend, with numbers up nearly six-fold from the early 1980s.

Common Merganser

Mergus merganser

ORIGIN OF NAMES “Merganser” from L. mergus, a diver.

NATURAL HISTORY These expert underwater hunters require fairly clear water to see their prey. Their long, thin bills have horny tooth–like projections that prevent slippery fish from escaping their grasp. This feature has earned them the epithet “sawbill.” Due to their large size, they are also called “Goosanders” in Europe.

Although they are mostly fish-eaters, Common Mergansers also forage for a diversity of aquatic insects, crayfish, mollusks, amphibians, small mammals, birds, and aquatic plants. These mergansers are often accused of depleting fisheries, but their total impact on fisheries is negligible since they rarely occur in large numbers in any given area. Like other diving ducks, Common Mergansers are clumsy on land and must run across water to take flight. Once flying, their long, straight bodies knife through the air just above the water’s surface, flashing white wing patches. They can be told from all other Sierra ducks by their sleeker profiles and long, narrow bills.

Common Mergansers nest in tree cavities or rock crevices near large streams or lakes; rarely they use artificial nest boxes. Breeding begins in April, and the young can navigate the swiftest streams within a day of hatching. One merganser duckling attempting to cross the Merced River at flood stage was sucked under the waves only to appear about 100 yards downstream, unhurt, and bobbing like a tiny cork. Females tend their young alone until they are independent after about five weeks.

STATUS AND DISTRIBUTION Aside from the ubiquitous Mallards, Common Mergansers are the most abundant and widespread breeding ducks in the Sierra, where they reside year-round.

West Side. Fairly common along most large creeks and rivers offering clear water and plentiful supplies of fish; most Sierra breeding records are from forested lakes and streams below about 8,000 feet; postbreeding birds can range to above 9,000 feet in the central Sierra in late summer and fall; flocks of 5 to 30 individuals remain on ice-free lakes and rivers at the highest elevations year-round, but most move to lower-elevation lakes, rivers, and reservoirs for winter; thousands winter on Lake Isabella.

East Side. Common at Lake Tahoe; fairly common to common in winter and during spring and fall migration at most large rivers, lakes, and reservoirs.

Red-breasted Merganser

Mergus serrator

ORIGIN OF NAMES “Red-breasted” for the coloration of breeding males; L. serrator, a sawyer, a reference to the species’ saw-toothed bill.

NATURAL HISTORY Primarily winter visitors to coastal estuaries and nearshore coastal waters, Redbreasted Mergansers rarely stray inland in winter. Like all mergansers, they are adept divers that forage for small fish; they also take mollusks, crustaceans, aquatic insects, and amphibians—captured in shallow water, but they are capable of diving up to about 30 feet. This species is often overlooked inland, especially when associating with the similar-appearing Common Mergansers. Male Redbreasted Mergansers are easily distinguished by their crested heads, grayish sides, and white neck rings set off by a reddish breast. Females, juveniles, and males in nonbreeding plumage are more difficult to identify but, compared to Common Mergansers, they are smaller, with more slender necks, thinner bills, and lack the distinct white throat patches of female Common Mergansers.

STATUS AND DISTRIBUTION Red-breasted Mergansers are winter visitors and spring and fall migrants, and there are no breeding records for the Sierra region.

West Side. Casual at Lake Almanor and Lake Isabella, mostly single birds seen far from shore.

East Side. Uncommon but regular fall, winter, and spring visitors to Lake Tahoe; rare at Boca Reservoir and Prosser Creek reservoirs, and from Crowley Lake south to Owens Valley.

Ruddy Duck

Oxyura jamaicensis

ORIGIN OF NAMES Ruddy describes the bright reddish plumage of breeding males; Gr. oxyura, sharp-tailed; L. jamaicensis, of Jamaica, where the type specimen of the species was collected.

NATURAL HISTORY Stout, chunky birds with thick heads and necks, Ruddy Ducks sit low in the water, and breeding males often cock their stiff tail feathers upward. Along with other “stiff-tailed ducks,” they differ from other waterfowl in many aspects of their biology. Males wear grayishbrown plumage for most of the year and do not molt into their bright chestnut or “ruddy” breeding plumage until March, much later than other ducks. Males display startling blue bills only when breeding, and these are used as part of elaborate and distinctive courtship displays to attract prospective females. Nest building occurs from mid- to late May, and nests are large mats of aquatic plants gathered into loose, floating platforms that rise or fall with changing water levels; most are screened from above by domes of overhanging plants. Females begin laying eggs by late May, often when nests are still under construction.

Ruddy Ducks become airborne by running across open water with their short wings beating furiously. They sink out of sight rather than flying to escape danger, much like grebes and loons. Unable to walk on land, they never stray from water, and larger lakes and ponds are preferred. They forage by skimming the water’s surface and by diving in shallow water up to about three feet; favored foods include aquatic invertebrates, zooplankton, and some aquatic plants—mostly seeds and roots.

STATUS AND DISTRIBUTION Ruddy Ducks may dot the surfaces of deep lakes, reservoirs, and sewage ponds of the Sierra in spring, fall, and winter, and nesting has been documented on both sides.

West Side. Fairly common spring and fall migrants and winter visitors, mostly in the foothills; rare individuals observed in large lakes as high as the Subalpine zone; nesting confirmed at Isabella Lake and possibly Lake Almanor; a family group was seen at 9,100 feet elevation at Upper Chain Lakes in Yosemite National Park.

East Side. Common to abundant in winter, fall, and spring, sometimes the most common ducks on large lakes and reservoirs; nesting confirmed in Sierra Valley, Tahoe Basin, Mono Basin, and Bridgeport Reservoir.

QUAIL

Family Odontophoridae

New World quail are medium-sized birds only distantly related to the quail of the Old World, but both are named “quail” for their similar appearance and habits. The Western Hemisphere species are in their own family and range from the cold, high deserts of Canada to the rainforests of southern Brazil. Members of this family generally have relatively short wings and tails, and short, powerful legs. While capable of short bursts of fast flight, especially when pursued or disturbed, they mostly travel on foot. Female quail usually lay large clutches of 10 to 20 buffy-white or brownish eggs and incubate them alone for 20 to 25 days. The precocial young can run after hatching and fly in about two weeks. This family includes 32 species but only 2, California and Mountain Quail, occur in the Sierra. The family name is derived from Gr. odontophoros, tooth bearing—a possible reference to the sharp toothlike beaks of juveniles.

Mountain Quail

Oreortyx pictus

ORIGIN OF NAMES “Mountain” for the species’ preferred habitat; quail, OF. quaille, possibly from the croaking or quacking sounds of a European species; L. ortyx, a quail; pictus from L. picta, painted, for the species’ bright colors.

NATURAL HISTORY Mountain Quail are the largest members of their family north of the tropics. Unlike other New World quail, males and females are nearly identical, with the latter having slightly shorter head plumes. These large, handsome quail are easy to miss but may be detected from April through early June by the loud, mellow wook or crow calls uttered by the males only. These ventriloquial calls are difficult to locate and at a distance might be mistaken for the single whistled notes of Northern Pygmy-Owls. These secretive birds seldom fly but instead run to dense cover when disturbed. The young are less cautious and may sometimes be seen at close range as their parents call anxiously, or even feign injury to distract human and other predators. Unlike California Quail, they rarely perch in trees, although scattered trees are usually present in their habitats.

Courting males often strut on the ground or on fallen logs to attract the attention of prospective mates. Females hide their nests in well-concealed hollows on the ground. Both parents care for the young after they hatch in late June or early July. Family groups remain together through the winter and are often joined by nonbreeding adults. Unlike California Quail, they do not typically band together with other families and winter coveys average 5 to 10 individuals.

A striking feature of the Mountain Quail’s annual cycle is the attitudinal migration in spring and fall, sometimes covering over 20 miles each way over a period of days or weeks, nearly all of it on foot. During migration, coveys may traverse atypical habitats such as dense coniferous forests and open, rocky areas. They winter below the heavy snow line down to the foothill chaparral, where some coveys live side-by-side with California Quail. When the heavy snow begins to melt in spring, Mountain Quail move upslope again.

Mountain Quail’s feeding habits are much like those of California Quail, suggesting that competition between these two species may have contributed to their altitudinal segregation while breeding. Foods of both species consist mostly of plant materials such as berries, seeds, flowers of perennial plants, along with a few insects—especially grasshoppers and ants.

STATUS AND DISTRIBUTION Mountain Quail visit foothill chaparral in fall and winter, but they mainly breed at higher elevations. Mountain chaparral and open forests with shrubby understories are preferred habitats, especially on steep slopes with dense thickets of manzanita, ceanothus, huckleberry oak, and other shrubs, interspersed with rocks or grassy openings.

West Side. Fairly common breeders from the Lower Conifer zone up nearly to tree line; in winter, most individuals descend below about 4,000 feet to foothill chaparral habitats to avoid heavy snow.

East Side. Uncommon residents of scrub habitats and open conifer stands up to the Subalpine zone; localized breeders in open Desert zone habitats south of the South Fork Kern River Valley, especially in the vicinity of desert oases where water is available; relatively easy to find (and to see) near Butterbredt Spring from April well into May; uncommon winter visitors to sagebrush flats along the eastern flank of the Sierra and the western Great Basin.

TRENDS AND CONSERVATION STATUS While the range of the Mountain Quail has contracted from the east, leaving the species reduced or extirpated in parts of Idaho, eastern Oregon, and Nevada, California populations appear to be stable.

California Quail

Callipepla californica

ORIGIN OF NAMES “California,” the state where the species was first collected; callipepla, beautifully dressed, from Gr. kallos, beauty, and peplos, a robe; L. californica, of California.

NATURAL HISTORY This exquisitely plumaged quail is the “state bird” of California. California Quail were a favorite game bird of native Sierra tribes, who snared them along their runways; head plumes and other feathers were used to adorn clothes and head-dresses. Backroad travelers in the Sierra foothills sometimes startle large coveys of California Quail, sending them running for cover or erupting into whirring flight in all directions. Rarely found above the foothills, they take shelter in chaparral, open oak stands, and streamside thickets but mostly feed in grassy openings. They do not migrate and may spend their entire lives in areas of only about two square miles. During the long, dry summers, they seldom venture far from streams, springs, or seeps that supply their daily water. At night, quail roost in heavily foliaged trees but will use dense shrubbery if necessary.

In fall and winter, California Quail feed and roost in large coveys numbering from about 25 to 60 birds. They make a variety of clucks and calls for courtship, aggression, alarm, and maintaining contact. When separated visually, covey members utter a three-note assembly call, chi-ca-go, with the second note higher than the others. This call is given frequently in spring by pairs that are separated and by single birds seeking mates. Hollywood film-makers often use these sounds for background in almost any setting, including movies shot in Africa and Australia, hoping their viewers will not notice this gross biological error. Based on old episodes of Star Trek, they may be the most widespread birds in the galaxy!

Males and females form monogamous pairs in late winter, gradually leaving the covey in late April or early May to find nesting sites—later than most resident birds. At this time, older unmated males establish small “crowing territories” to attract unpaired females. Their cow calls, similar to the last note of the assembly call, are repeated several times per minute, usually from exposed perches in shrubs or trees. Each mated male defends his mate from other suitors but does not hold a nesting territory. Females construct nests by lining a small, well-hidden, ground depression with plant stems and grasses. Young hatch in early June and stay with both parents through their first winter. In late summer, two or more of these family groups band together, along with nonbreeding individuals, to form a covey once again.

The staple foods of California Quail are seeds and leaves of herbaceous plants, especially clover, lupines, tips of grasses, but acorns, fruits, wild berries, and large insects are also important. They usually forage on the ground, picking food from plants or scratching like chickens. Sometimes they move up into shrubs or even leap off the ground to snatch insects or seeds from plants.

STATUS AND DISTRIBUTION California Quail occur on both sides of the Sierra; while still more widespread on the West Side, they have become abundant in many East Side areas.

West Side. Common and widespread in the low foothills from annual grasslands and oak savannas to the Lower Conifer zone; primarily found in foothill chaparral, open oak woodlands, and riparian woodlands near a source of water and grassy areas for foraging; avoids dense conifer stands and is rare or absent above about 3,500 feet in the central Sierra; common in open Desert zone habitats, in the vicinity of oases, as in the South Fork Kern River Valley.

East Side. Uncommon to locally abundant throughout; recorded up to 8,400 feet at Aspendell (Inyo County); their range has expanded from presettlement times likely due to a combination of habitat changes, artificial water sources, and introductions; locally common near desert oases such as Butterbredt Spring.

TRENDS AND CONSERVATION STATUS Professional market hunters killed enormous numbers of California Quail during the 19th century. Quail have very high reproductive rates, so while they are probably less numerous now than before that era, this decline is due mostly to habitat changes, fire suppression, and land development. With enforced hunting limits, these gentle birds are once again common in suitable foothill habitats. Data from Sierra Christmas Bird Counts show a significant positive population trend in the past 30 years due largely to increases from nearly all the East Side count circles.

FOWL-LIKE BIRDS

Family Phasianidae

These stout-bodied birds with strong feet and legs are well suited for dwelling on the ground. Though capable of short, swift flights, they mostly run to escape danger. The turkeys, pheasants, ptarmigans, and chukars of the Sierra were introduced for hunting. The two native grouse, Greater Sage and Sooty, also are considered game birds, despite their declining populations. All Sierra species nest on the ground, making them vulnerable to predators, but the drab, mottled females are difficult to spot when motionless on their cryptic nests. Females usually lay 5 to 15 yellowish, buff, or reddish-brown eggs marked with purple or dark brown spots and incubate them alone for about 20 to 25 days. Their precocious young are well developed upon hatching, with strong legs, open eyes, and thick coats of down. Within hours the young leave the nest and begin feeding while one or both parents lead them to food and provide protection until they are capable of flight in about two weeks. This large, diverse family occurs worldwide except in the Antarctic and contains about 145 living species; 2 of these are native to the Sierra and 4 species have been successfully introduced to the region. The family name is derived from Gr. phasianos, a pheasant.

Chukar

Alectoris chukar

ORIGIN OF NAMES “Chukar” may refer to the chuck-chuck-chuck vocalizations of the species; alectoris from Gr. alektor, a cock.

NATURAL HISTORY First introduced from northern India (now Pakistan) to North America in the late 1800s, these medium-sized game birds are now established in many areas of the arid West. Subsequent introductions included birds native to mountainous areas from the Alps to the Himalayas, and these were mixed in game farms so that most wild populations now have an uncertain heritage.

Chukars thrive only on steep, rocky hillsides, in open areas with less than 20 inches of precipitation per year, and they avoid cultivated agricultural fields. To escape danger, they run up steep slopes and only take flight when necessary to avoid hunters and their dogs and other predators. At night they roost among rocks or shrubs. Green leaves, small seeds, and a few insects make up their diet. Little is known about the nesting habits of this species in California, since their nests are hard to find and few have ever been discovered in the state. In other areas they create simple grass-lined scrapes concealed under rocks or brush. Courtship begins in mid-March, and pairs with failed first nesting attempts may build second or third nests until at least mid-August. During the dry summer months, coveys of up to 40 or more birds concentrate near sources of water such as springs, natural seeps, and along brushy desert creeks. Similar to Mountain Quail, they descend below the heavy snow line for the winter, mostly on foot.

STATUS AND DISTRIBUTION First introduced to California in 1932, Chukars are now established on both sides of the Sierra, with the largest populations east of the crest.

West Side. Uncommon; breeding populations in the foothills of Fresno County up to about 12,000 feet in Tulare and Kern Counties (including the Kern Plateau), and possibly in the foothills below Yosemite National Park, where first introduced in the 1960s at the Red Hills south of Chinese Camp, and Horseshoe Bend Mountain near Lake McClure.

East Side. Fairly common and widespread below the pine forests along Walker Creek and in the Bridgeport Valley and south to the Mono Basin, and just east of the Sierra in the Bodie Hills; locally fairly common in eastern Lassen, Sierra, and Plumas Counties; fairly common to common in the vicinity of several desert oases south to at least Butterbredt and Jawbone Canyons; has been recorded in Owens Valley.

Ring-necked Pheasant

Phasianus colchicus

ORIGIN OF NAMES “Ring-necked” for the male’s bright white neck ring; pheasant from Fr. faisan, a pheasant; Gr. phaisianos, a pheasant; cholchius for the Colchis region near the Black Sea in central Asia, where the species is native.

NATURAL HISTORY Ring-necked Pheasants are native to Asia and have been widely introduced to suitable habitats throughout North America, where they are now the most widely hunted upland game bird. Pheasants prefer grain or hay fields, often those with weedy margins or wetland vegetation nearby, where they forage for cultivated grain seeds, fruits, nuts, and insects. Highly adapted to life in cultivated fields and other disturbed areas, Ring-necks probably do not compete with native species of grouse or quail for food or habitat.

The bold plumage of adult males makes them easy to spot in open fields and sparse grasslands, but they can disappear entirely in even the sparsest cover when pursued by hunters or their dogs. Pheasants “freeze” until almost stepped on before erupting into flight with an enormous racket of beating wings and cackling calls. The subtle brown plumage of females enables them to stay mostly hidden, even in plowed fields, but they are almost as noisy and conspicuous as males when flushed. In early April, females begin to select their nest sites in tall vegetation near their winter foraging areas. Hens excavate shallow depressions where they toss nearby twigs, leaves, or grasses together. Chicks can fly and forage independently at about two weeks of age.

STATUS AND DISTRIBUTION Ring-necked Pheasants were introduced into California as early as 1855. They are now abundant residents in agricultural areas of the Central Valley but uncommon or absent from most of the foothill areas.

West Side. Uncommon in the Kern River Valley, the only well-established population; birds are found consistently on a couple of low foothill Christmas Bird Counts in Placer and Tulare Counties.

East Side. Uncommon residents of agricultural fields near Honey Lake with numbers on recent Honey Lake Christmas Bird Counts lower than those seen in the 1980s and 1990s; released into the Owens Valley in the early 1900s with numerous other introductions by the California Department of Fish and Game until 1977; confirmed breeding near Lone Pine (Inyo County) in 2003, but most introductions have been unsuccessful.

Greater Sage-Grouse

Centrocercus urophasianus

ORIGIN OF NAMES “Sage-Grouse” for their dependence on sagebrush; Gr. centrocercus, sharptailed; urophasianus from Gr. oura, tail, and L. phasianus, a pheasant.

NATURAL HISTORY Perhaps the most inspiring Sierra birding experience is waking up in the predawn chill to view the elaborate and spectacular strutting displays of the Greater Sage-Grouse, the largest native North American grouse. As soon as the snow starts to clear in early March, males gather at traditional “lek” sites to attract females on open hillsides, grassy swales, recently burned areas, or dry lakebeds, surrounded by sagebrush—the species’ preferred nesting habitat. Leks are collective display grounds composed of small, individual territories defended by different males. Strutting displays involve a complex sequence of stereotyped postures characterized by vertical fanning of the long, sharp tail feathers, lowering of wings, and inflating of air sacs to display two olive-green skin pouches. Individual displays last about three seconds but are repeated many times during the early dawn hours. Breeding displays also include an array of strutting calls, fighting calls, low grunts, and loud popping sounds.

Displays and vocalizations serve as an alternative to physical aggression, and displaying males rarely engage in direct physical combat with other males. Leks consist of 20 or more competing males and the oldest ones, “master cocks,” are the most successful. Typically one or a few males achieve more than 90 percent of all copulations. Clusters of hens gather together and serve as a sexual stimulus for other females that engage in precopulatory squatting before accepting the advances of the dominant males. After hours of preparation, the copulation only lasts a few seconds. Birders and photographers should exercise extreme caution when viewing Sage-Grouse strutting displays and should only view them from well-concealed sites at a distance of 100 yards—or more.

Once fertilized, the hens leave the strutting grounds and seek out nesting sites under the overhanging cover of sagebrush or tall grasses to provide thermal cover and protection from predators. Hens care for their precocial young for at least several weeks. Young are capable of foraging on their own within a few hours of hatching, and insects such as ants and beetles are an important component of their diet. Preferred foods of adult Sage-Grouse include the fresh leaves and buds of sagebrush as well as grasses, flowers, fruits, and a few insects; in winter, Sage-Grouse subsist entirely on sagebrush leaves, a diet unique among North American birds.

STATUS AND DISTRIBUTION Greater Sage-Grouse are residents of sagebrush flats in the Great Basin, and their range extends into the eastern Sierra.

West Side. No records.

East Side. Uncommon to rare and highly localized; some lek sites in the region persist at isolated locations near Honey Lake, west of Bridgeport Valley, Mono Basin, and Long Valley (Mono County); also just east of the Sierra in the Bodie Hills and White Mountains (Mono and Inyo Counties).

TRENDS AND CONSERVATION STATUS Due to their dependence on sagebrush, Sage-Grouse are adversely affected by land management activities that degrade their habitat, such as overgrazing by cattle and wild horses, unnatural colonization of sagebrush habitats by Utah junipers and pinyon pines, uncontrolled and destructive wildfires, and fragmentation by roads and housing subdivisions. Historical hunting pressure was also a factor in the species’ decline, but strict controls since the 1980s suggest that hunting is not a current threat to their population. Such recreational activities as off-highway vehicles and uncontrolled viewing and photography of active leks can result in reproductive failures. “Green energy” projects, such as solar and wind, that destroy thousands of acres of pristine desert or sagebrush habitat, are also a significant but unmeasured threat. For these reasons, the species was included on the 2008 list of California Bird Species of Special Concern.

White-tailed Ptarmigan

Lagopus leucurus

ORIGIN OF NAMES “White-tailed” for the species’ distinctive field mark; “ptarmigan” is probably derived from a Gaelic word “tarmachan,” the “p” is silent and based on historical misspelling; Gr. lagopus, hare-footed, a reference to the species’ feathered tarsus and feet; Gr. leucurus, white-tailed.

NATURAL HISTORY Brown and white in summer, these Arctic grouse molt into pure white plumage in winter to match their snowy surroundings. White-tailed Ptarmigan are silent most of the time, but both males and females utter loud “flight screams” when flushed, and territorial males emit “gobbling” calls to attract females. Males are generally monogamous, but some are polygynous and court two or more females. Pair formation begins from late April to mid-May. After copulation, females use their feet and bills to excavate shallow scrapes on the ground near rocks in snow-free areas. These are later filled with nearby stems and grasses to form a shallow bowl. Typically females lay one egg per day, but during severe snow storms up to eight days may lapse before another egg is laid. The young are brooded by both parents until they can fly and forage alone; broods remain together until the following spring.

White-tailed Ptarmigans are native to Alaska, western Canada, and isolated pockets of the Rocky Mountains—but not the Sierra. The California Department of Fish and Game introduced White-tailed Ptarmigans to the Sierra simply because the Alpine zone had no game birds for hunters. This is especially ironic because nearly all currently inhabited sites are in National Parks where hunting is prohibited. Although there is no documentation of detrimental effects of this introduction, ecologists have long known that non-native animals can have unpredictable, and sometimes disastrous, effects on native plants and animals, which have coevolved over thousands or millions of years.

STATUS AND DISTRIBUTION All White-tailed Ptarmigans in the Sierra originated from a transplant of about 70 birds from Colorado released at two sites near Eagle Peak and Twin Lakes, Mono County, in 1971 and 1972 (Frederick and Gutiérrez 1992). Since then, the species has spread to about 50 miles north, 20 miles west, and 70 miles south of the release sites.

West Side. Uncommon residents; recorded in Humphrey’s Basin and Dusy Basin in Kings Canyon National Park and as far north as Carson Pass, El Dorado County; breeding populations occur near the crest in the Yosemite Sierra near Gaylor Lakes, Granite Lakes, Mono Pass, and Dana Plateau, and as far west as Mount Hoffman, near the geographic center of Yosemite National Park.

East Side. Uncommon residents, mostly confined to the Alpine zone along the crest, but spring sightings at about 8,000 feet in Lundy Canyon, Mono County, suggest downslope movements in winter to avoid heavy snow; also observed near Pine Creek, Green Lake, Brown Lake, and Piute Pass, Inyo County.

Sooty Grouse

Dendragapus fuliginosus

ORIGIN OF NAMES “Sooty” for dark plumage; formerly called Blue Grouse, now considered a distinct species from Dusky Grouse (D. obscurus); see “Status and Distribution” below; Gr. dendragapus, tree loving; fuliginosus from L. fuligo, sooty.

NATURAL HISTORY Sooty Grouse are more often heard than seen. Males of this species congregate in loose “hooting groups” from late April to early July to proclaim their territories with a series of resonant, booming calls. These calls are lower in pitch than those of any other Sierra bird, so low that some people cannot hear them. Two yellow air sacs on the neck, usually hidden, are inflated to produce these unmistakable notes. Finding a hooting male is seldom easy, because he makes ventriloquial calls from a hidden perch high overhead in the foliage of a dense conifer. Visitors to higher forests may hear, and feel, these haunting calls echoing through the woods for hours at a time.

Most Sooty Grouse in the Sierra breed in the Upper Conifer zone, where they can be found in open or partly brushy slopes with nearby stands of densely foliaged conifers for roosting and hooting. Large trees are preferred—especially Douglas-firs, white firs, red firs, and Jeffrey pines. Adult males arrive on breeding territories by early March, followed shortly thereafter by females and yearling males. Throughout the nesting season, the promiscuous males remain on their territories and attempt to court and mate with receptive females attracted by their calls. Once mated, a female prepares a nest by lining a shallow depression on the ground under a shrub, tree, or log with leaves and grasses.

The young eat mostly insects, a source of protein, for at least ten days after hatching then switch to conifer needles and seeds. By late summer, mothers with young disperse both upslope and downslope from their nesting grounds, feeding in meadows and brushy hillsides, where they are often surprisingly tame. An encounter with a family group inspired John Muir (1901) to write: “One touch of nature makes the whole world kin; and it is truly wonderful how love-telling the small voices of these birds are, and how far they reach through the woods into one another’s hearts and into ours.” During spring, summer, and fall, Sooty Grouse forage mostly on the ground, eating seeds, berries, green shoots, and insects. Adults also fly up into conifers to browse on needles and buds. These hardy birds survive high-elevation winters by taking shelter in dense firs, pines, and hemlocks and eating needles, buds, and pollen cones.

STATUS AND DISTRIBUTION In 2006 the American Ornithologists’ Union split Blue Grouse into Sooty Grouse occurring in the Sierra, Cascades, and coastal ranges of California, Oregon, and Washington, and Dusky Grouse that live in the Rocky Mountains and Great Basin. Sooty Grouse undertake both upslope and downslope movements in spring and fall. In the Pacific Northwest they are known to migrate upslope for the winter, and birds at Sequoia National Park have also been observed to undertake such “backward” migrations.

West Side. Uncommon residents of the Upper Conifer zone, males and some females wander up to tree line after breeding where they remain until late fall; rare in Lower Conifer zone in fall and winter.

East Side. Uncommon residents of ponderosa and Jeffrey pine forests up to the Subalpine zone; populations at Sagehen Creek (Nevada County) remained at their breeding elevations through the winter but similar studies are lacking from other areas.

TRENDS AND CONSERVATION STATUS The “Mount Pinos” Sooty Grouse (D. f. howardi) is a distinct subspecies restricted to the southern Sierra, south of Kings Canyon National Park, including the Piute Mountains, as well as ranges to the south of the Sierra including the Tehachapi Mountains and Mount Pinos. Recent surveys suggest that they may be extirpated from most of the southern portion of their historical range. Extensive surveys in 2002 in the Greenhorn Mountains (northernmost Kern County) found only eight birds in what is likely now the southern edge of their range. Continuing threats include habitat degradation due to harvest of large trees, fire suppression and uncontrolled wildfires, and livestock grazing. This subspecies was added to the list of California Bird Species of Special Concern in 2008.

Wild Turkey

Meleagris gallopavo

ORIGIN OF NAMES Turkey, considered foreign and exotic when the species was first introduced to Europe in the 16th century; a possible reference to Asia Minor, a source of exotic goods at that time; Gr. melagris, spotted, for the species’ patterned plumage; L. gallopavo, from gallo, a cock, and Sp. pavo, a turkey.

NATURAL HISTORY With their dazzling, iridescent bronze plumage, Wild Turkeys are elegant versions of common barnyard turkeys, a breed domesticated during pre-Columbian times in Mexico. Wild Turkeys are not native to California, but birds captured in Mexico were first introduced to mainland California for hunting in 1908. While most early introductions failed, subsequent releases over many decades were more successful and the species is now widespread in suitable habitats throughout the state. Most of the successful introductions to California were from wild populations in Mexico, Virginia, and Texas. Attempted introductions by the California Department of Fish and Game, U.S. Forest Service, and the National Wild Turkey Federation at high elevations of Sierra, Nevada, and Placer Counties as recently as 1997 should be discouraged because this species may compete with native species of quail and grouse with unknown consequences. They have also been observed to scour entire hillsides for snakes, lizards, and invertebrates having obvious but unmeasured impacts on those species.

Turkeys roost in trees but forage on the ground in forest openings, eating insects, green plants, seeds, acorns, and fruit. Throughout the year Wild Turkeys associate in groups, which consist during the breeding season of a “gobbler” male and his harem of four to six hens. In the Sierra the breeding season extends from late March until August, with a peak in May and June. Prior to pair formation, three to six males may strut together to attract a large group of females. The polygynous males perform courtship, a series of gobbling and strutting displays to attract females to be added to their harems. Conspicuous during courtship, fertilized hens sneak away from the immediate breeding area and are secretive when preparing to nest. They create shallow scrapes for nests and line them with leaves and grasses. Young are tended by hens alone through the winter until the following breeding season—female poults tend to remain with their mothers longer than males. With the inclusion of juveniles, winter flocks are larger than breeding flocks, and up to 100 birds might be seen foraging together on an oak-studded hillside.

STATUS AND DISTRIBUTION In the Sierra, Wild Turkeys spend most of the year in the Foothill zone, but they can be fairly common in the Lower Conifer zone in summer; postbreeding birds have been seen up to 10,000 feet on the Kern Plateau of the southern Sierra. In winter, they move as much as 50 miles downslope in search of areas with plentiful food and little snow, especially in foothill oak woodlands and chaparral.

West Side. Common to abundant in most areas of the foothills.

East Side. Uncommon; established populations near Honey Lake, in Alpine County, and near Topaz Lake.

TRENDS AND CONSERVATION STATUS Data from Breeding Bird Surveys and Sierra Christmas Bird Counts confirm the stunning increase in numbers and expansion of range for this species. In less than 30 years, Wild Turkeys have gone from unrecorded to abundant throughout the western foothills. Noted on only a couple of Sierra Breeding Bird Survey routes prior to the late 1980s, Wild Turkeys are now found consistently on more than 40 percent of the routes. Impacts to other species from this invasion are not yet evident.

LOONS

Family Gaviidae

Called “divers” in Europe, loons are sleek-bodied and superbly adapted to aquatic habitats but are almost helpless on land. Laterally flattened legs, set far back on their bodies, do not enable them to walk or stand, so loons can only move on land by sliding on their bellies. Unlike grebes, which have lobed toes, loons have webbed feet. They are also strong fliers but cannot take off from land; instead, they take flight after a long running start over open water, often into a stiff wind. Once aloft, they fly with quick, shallow strokes on slender, pointed wings. On a dive, their large, paddle-like feet propel them to great depths. Genetic studies indicate that loons are unlike any other living order of birds, not related (as once thought) to grebes. Fossil evidence shows that they have an ancient lineage dating back more than 65 million years. Males and females share identical breeding and winter plumages, but males are usually larger. There are only five species of loons worldwide, and all of them breed in North America. Two species, the Pacific and Common Loons, regularly occur in the Sierra. The family name is derived from L. gavia, a seabird.

Pacific Loon

Gavia pacifica

ORIGIN OF NAMES “Loon” may be a reference to the species’ wild calls, “crazy as a loon”; L. gavia (see family account above); L. pacificus, of the Pacific.

NATURAL HISTORY Pacific Loons consume mostly small fish captured by diving in deep, open water. They often swim with their heads and necks partially submerged, “snorkeling” for fish that they pursue at depths up to 70 feet. Behavior and habitat preference in the Sierra are very similar to Common Loons (see account below).

STATUS AND DISTRIBUTION Pacific Loons breed in Alaska and northern Canada and migrate south in small flocks to spend the winter along the Pacific Coast. In California most of the population winters in protected bays and coastal estuaries not far from shore, but migrants stray to large, inland water bodies including in the Sierra.

West Side. Uncommon fall, winter, and spring visitors; observed in most years at foothill reservoirs; rare above the Foothill zone but almost annual fall and winter records from Lake Almanor and other large mountain lakes and reservoirs up to the Subalpine zone.

East Side. Uncommon visitors to Lake Tahoe and large reservoirs such as Stampede Reservoir (Sierra County), Boca Reservoir, and Bridgeport Reservoir and Lake Crowley, and June Lake from November through May.

Common Loon

Gavia immer

ORIGIN OF NAMES Sw. immer, ember, blackened ashes, a reference to the dark upperparts of breeding adults.

NATURAL HISTORY Common Loons have not been recorded as a California breeding species since the mid-1920s, when a few pairs and young birds were observed at Eagle Lake and other lakes near Lassen Volcanic National Park. Among the world’s most accomplished diving birds, Common Loons make foot-propelled dives that may exceed depths of 200 feet. Small fish are their preferred prey, but they also consume crustaceans as well as aquatic insects and plants, including algae. Although capable of extremely deep dives, Common Loons usually forage in relatively shallow, nearshore waters. While swimming along the water’s surface, they may partially submerge their bills and cock their heads to “snorkel” for fish underwater. Upon spotting a prey item, they roll forward slowly in a smooth arc, with wings closed, and are capable of long underwater pursuits. These large-bodied loons ride low in the water when actively foraging, but float higher when resting or preening. Usually observed in winter plumage in the Sierra, Common Loons molt into breeding plumage by mid-April prior to migrating north to breed. Although rarely heard, these birds do give eerie yodeling calls from time to time, even in midwinter.

STATUS AND DISTRIBUTION Visitors from northern breeding grounds, most Common Loons in California remain in coastal waters. Each year, however, many regularly appear on large lakes and reservoirs of the Sierra.

West Side. Fairly common and regular fall and winter visitors to such large reservoirs as Lake Almanor, Millerton Lake, Lake Success, and Lake Isabella; rare nonbreeding individuals remain through summer; casual in late summer and fall at large Subalpine lakes, such as Tenaya Lake in Yosemite National Park.

East Side. Fairly common in fall, winter, and spring at large water bodies, such as Lake Tahoe, Topaz Lake, Stampede Reservoir (Sierra County), Boca/Prosser Reservoirs, and Bridgeport Reservoir, Crowley Lake, and June Lake but usually depart when substantial areas of open water freeze.

TRENDS AND CONSERVATION STATUS While late-19th century accounts documented Common Loons nesting just north of the Sierra at Eagle Lake, and at a few other large lakes above 5,000 feet east of Mount Lassen, they were probably extirpated as a breeding species in California by the early 1900s. The following account by C. H. Townsend (1887) is one of the only descriptions of Common Loons nesting from the Lassen region: “I waded out to a narrow sand bar . . . upon which a (Common) Loon had been sitting, and found her nest or rather egg . . . which was lying on the sand.” The cause of the Common Loon’s disappearance as California breeders is unknown, but it may have been related to human disturbance of nest sites. Studies in other parts of North America have shown that the mere presence of boats, even a single canoe passing too close, can cause Common Loons to abandon their nests and young. Formerly, Common Loons were included on the list of California Bird Species of Special Concern (Remsen 1978), but they were removed from this list since extirpation as a breeding species in California happened more than 100 years ago.

GREBES

Family Podicipedidae

Wedded to water at all seasons, grebes feed, sleep, court, and nest on water. At a distance, they look somewhat like ducks but tend to sit higher on the water and have shorter bodies, more slender necks, and sharp, pointed bills. Rather than webbed feet, they have individually lobed toes that fan out when pushed through water, as do coots and phalaropes. Grebes can dive 20 feet or more and stay submerged for up to a minute. Similar to loons, grebes swim underwater with great strength and agility, propelled by legs set so far to the rear that they cannot walk upright on land. They are rarely seen in flight, and even when pursued by predators, they usually flee by diving. Most grebes migrate at night, and a few species (such as Eared Grebes) travel thousands of miles between their breeding and wintering grounds. Female grebes usually lay three to six whitish eggs and cover them with moist nesting material when leaving their nests, causing eggs to become stained reddish-brown before they hatch. Both adults participate in incubating the eggs for about 20 to 25 days. Information on the behavior of nestlings is lacking for many species, but most young grebes attain flight after about 10 weeks.

All grebes have soft, thick plumage. Feathers are consumed incidentally while preening and form into balls in grebes’ stomachs, which may function to protect the linings of their stomachs and intestines from being punctured by fish bones. Feather balls also serve as the nuclei of pellets that are regurgitated to eliminate bones and other indigestible materials. Of about 20 grebe species in the world, 7 occur in North America, and 5 of those occur regularly in the Sierra. The family name was derived from L. podicis, rump, and pedis, a foot, and roughly means “rump-footed.”

Pied-billed Grebe

Podilymbus podiceps

ORIGIN OF NAMES Podilymbus, a diving bird, from L. podiceps, a grebe, and Gr. kolumbos, a diving bird; podiceps ( see family account above); “grebe” is an OF. word of unknown origins.

NATURAL HISTORY Generally solitary, with subdued brownish plumage, Pied-billed Grebes may go unnoticed when swimming along the dense vegetation at a pond’s margin. They dive for aquatic insects, crustaceans, or small fish in shallow waters and consume smaller quantities of tadpoles, mollusks, and aquatic plants. They also frequent deeper, open waters where they rest with other grebes or with larger coots and ducks. Most water birds take flight when predators approach, but Pied-billed Grebes sink quietly beneath the surface and reappear amid floating plants with only their heads out of water. They are typically found in quiet ponds, backwater sloughs, lakes, and reservoirs. Although they occur on water bodies from one-half to over 100 acres in size, Pied-billed Grebes are most often seen on ponds ranging from 1 to 5 acres. They prefer open water bordered by dense cattails, bulrushes, and other emergent vegetation.

Most grebes are colonial when nesting, but Pied-billed pairs are solitary. Both parents gather dead and rotting plant materials to build a thick mat nest that occasionally floats free but is usually anchored to plants growing from the bottom ooze. Their breeding season extends from about mid-March to mid-September, though peak breeding activity occurs from late June to early July. Each pair defends a small territory around the nest, where the young are fed and reared. Newly hatched chicks often ride on the adults’ backs or hide beneath their wings during dives.

STATUS AND DISTRIBUTION Unlike other grebes, most Pied-billed Grebes do not migrate to salt water for the winter and prefer to reside year-round in freshwater habitats.

West Side. Fairly common residents and nesters throughout the foothills, they also nest rarely up to the Upper Conifer zone but are scarce anywhere above about 5,000 feet; a few breeding pairs have been found above 7,000 feet in the Subalpine zone of Plumas County, and postbreeding birds occur up to about 8,000 feet in Yosemite and Sequoia National Parks during late summer and fall; flocks of up to 300 individuals have been seen at Salt Spring Valley Reservoir (Calaveras County) in winter.

East Side. Fairly common permanent residents and nesters below about 7,000 feet, rare fall migrants have been seen at Alpine lakes up to about 9,000 feet in Yosemite National Park; numbers increase noticeably in October and November when they congregate at large reservoirs such as Crowley Lake and Bridgeport Reservoir; rare in winter, most depart before their preferred freshwater habitats freeze over.

Horned Grebe

Podiceps auritus

ORIGIN OF NAMES “Horned” for the tufts of feathers on the heads of breeding adults; L. auritus, eared; for unknown reasons taxonomists applied the scientific name to this species instead of the Eared Grebe, which was named instead for its neck color.

NATURAL HISTORY Foraging Horned Grebes dive after small fish, crustaceans, and aquatic insects. Similar to other grebes, they also dive to escape danger and can swim for long distances before coming to the surface. Although they sometimes share open waters of large lakes and reservoirs with Eared Grebes, Horned Grebes tend to be much less gregarious and are less likely to occur in large flocks on their wintering grounds or during migration.

STATUS AND DISTRIBUTION Horned Grebes do not breed in California, and most of the state’s visitors are found in coastal waters from October through April. A few, however, are drawn to lakes and reservoirs of the Sierra. This species is probably overreported, especially in fall when transitional plumages of Eared Grebes can blur the distinction between these species.

West Side. Uncommon fall, winter, and spring visitors to Lake Almanor, Millerton Lake, Avocado Lake (Fresno County), Lake Isabella, and other large lakes and reservoirs.

East Side. Uncommon to rare spring and fall visitors to such lakes as Boca Reservoir, Lake Tahoe, Topaz Lake, Grant Lake (Mono County), and Crowley Lake.

Eared Grebe

Podiceps nigricollis

ORIGIN OF NAMES “Eared” for the feather tufts; nigricollis, black-necked, from L. niger, black; L. collum, neck.

NATURAL HISTORY These small, thin-billed grebes congregate at Mono Lake in enormous numbers during fall migration to feed on the superabundant brine shrimp that thrive in the lake’s highly alkaline and saline waters. At the peak of their fall migration, they may consume more than 60 tons of brine shrimp daily (Winkler et al. 1977)! They also consume alkali fly larvae in shallow, nearshore waters, and the flies represent about 10 percent of their diet. Huge quantities of food are needed because the grebes are molting and rebuilding their fat reserves before continuing their migration. At freshwater habitats elsewhere in the Sierra, Eared Grebes consume mostly insects (adults and larvae), crustaceans, mollusks, and occasionally small fish and tadpoles. They usually forage by diving and capturing prey underwater but sometimes take insects from the water’s surface.

Mono Lake is the Eared Grebe’s largest fall staging area in North America. From breeding grounds across the western United States and Canada, birds begin to arrive at the lake in June, and the summer flock may contain more than 25,000 birds, mostly juveniles and nonbreeders. Postbreeding Eared Grebes arrive at Mono Lake at rates of up to 10,000 birds per day in late summer and fall, and numbers may peak at more than a million birds in September and October. Large numbers of Eared Grebes usually remain at Mono Lake until late November, when the brine shrimp population collapses and the grebes continue their migration on to the Salton Sea, San Francisco Bay, or the Gulf of California.

Nesting activities extend from late April until late September, with a peak from June through mid-August. Both sexes participate in building the nest, a hollowed-out mound of rotting vegetation hidden by similar material and located on the ground or floating and anchored to submerged, upright plants. Juvenile Eared Grebes can fly about 45 days after hatching and promptly begin their fall migration.

STATUS AND DISTRIBUTION Eared Grebes nest in freshwater habitats, but most seek highly alkaline and saline waters during migration through the Sierra and on their wintering grounds.

West Side. Fairly common year-round residents only at Lake Almanor and at Lake Isabella, where hundreds or thousands overwinter and a few remain through the summer; elsewhere, uncommon and irregular visitors to large lakes and reservoirs in fall, winter, and early spring; rare migrants have been seen at large Subalpine and Alpine lakes of Yosemite and Kings Canyon National Parks in late summer and fall.

East Side. Common nesters in marshes of the Great Basin, just east of the Sierra, and small numbers nest locally in shallow wetlands near large waters in the eastern Sierra, including Honey Lake, Crowley Lake, and Bridgeport Reservoir; uncommon to absent in winter except for Mono Lake, where the local Christmas Bird Count tallies hundreds or even thousands some years, and the Reno area, where double-digit numbers are not unusual.

TRENDS AND CONSERVATION STATUS A historic 1994 decision by the State Water Resources Control Board should ensure that Mono Lake’s waters will not become too alkaline and salty to support abundant brine shrimp and alkali flies for Eared Grebes and other water birds. While their habitat appears secure in the eastern Sierra, mortality in other parts of the Eared Grebe’s range, including the unexplained, recent die-offs of up to 150,000 birds at the Salton Sea, Imperial County, could affect the number of birds at Mono Lake and at other important western staging areas.

Western Grebe

Aechmophorus occidentalis

ORIGIN OF NAMES Aechmophorus from Gr. aichme, spear, and phoreus, bearer; L. occidentalis, western.

NATURAL HISTORY These largest of North American grebes (along with Clark’s Grebe, see account below) are also the most widespread grebes in the Sierra. Scanning across an expanse of open water, birders often spot these large diving birds as specks of white bobbing in the distance. A closer look reveals the bright white breasts and long, snake-like necks of Western Grebes. They may appear headless, because they often sleep with heads and necks drawn back with bills pointing forward. They feed by diving and pursuing their prey under water, and they usually forage in water at least four feet deep. Westerns (and Clark’s) have a neck mechanism, unique among grebes, that permits them to thrust their heads forward like spears (a fact painfully learned by one of the authors when rescuing a grebe tangled in fishing tackle). A similar mechanism has been well described for herons but has not been studied in grebes. Westerns consume more fish than most other grebes, but they also eat mollusks, crustaceans, insects, and rarely amphibians and aquatic plants. They dive to avoid predators and can remain submerged for up to a minute.

In the breeding season, Western Grebes require a large extent of open water for feeding and resting, a good supply of fish, and cattails, tules, or flooded riparian trees for securing their floating nests. Pairs of Western Grebes perform elaborate courtship displays, swimming side by side then running rapidly with their bodies erect, heads and bills pointed skyward, and only their feet touching water. In the Sierra, courtship mainly occurs from April to May, and nests can be occupied from May until August; fall nesting has been documented at Lake Isabella, with downy young riding on their parents’ backs. They are monogamous breeders, nesting in dense colonies that may contain hundreds of closely spaced nests. Nests are composed of decaying aquatic plants and some green plants mounded on mud or submerged plant root masses in shallow water. They also construct floating platforms of dead plant material and anchor these to emergent plants. Parents take turns incubating the eggs, and pairs will renest if their nests are lost to predators. The precocial young leave their nests at hatching and ride on the backs of both parents. Young can swim and feed themselves soon after hatching, but their parents still feed them for four or five weeks, until they are nearly full-grown.

STATUS AND DISTRIBUTION Outside the breeding season, Western Grebes are often found in significant numbers on most large lakes and reservoirs.

West Side. Common nesters at Lake Almanor in the north and at Lake Success and Lake Isabella in the south but apparently do not breed elsewhere on the West Side; fairly common nonbreeding visitors to nearly all large foothill reservoirs; rare visitors to large Subalpine and Alpine lakes in summer and fall, especially if fish are present.

East Side. Common from April through November at Boca Reservoir, Prosser Creek Reservoir, Lake Tahoe, Topaz Lake, June Lake, Bridgeport Reservoir, and Crowley Lake; common nesters at the latter two reservoirs; casual to rare in winter.

TRENDS AND CONSERVATION STATUS Western Grebes, like all colonial water birds, are vulnerable to development around lakes and reservoirs and to other human disturbance near their nesting colonies. Personal watercraft and motor boats have been observed near breeding colonies in flooded riparian forests at Lake Isabella and could be a serious disturbance factor there and at other Sierra nesting locations. Drawdown of water for hydroelectric generation during the breeding season has marooned nests in the past at Lake Almanor. Several thousand Western and Clark’s Grebes died at Lake Isabella in August and September 2005; the suspected cause was a bacteria bloom that produced neurotoxin that poisoned fish and secondarily poisoned grebes as well as other water birds such as herons and ducks. A similar die-off occurred at Lake Success in 2006, and mortality probably occurs at lower levels at these and other reservoirs in most years.

Clark’s Grebe

Aechmophorus clarkii

ORIGIN OF NAMES “Clark’s” for J. H. Clark (1830–?) a surveyor and naturalist who collected the first specimen of this species (not the Clark of the Lewis and Clark Expedition, see Clark’s Nutcracker account).

NATURAL HISTORY First described in 1858, Clark’s Grebes were not considered a full species by the American Ornithologists’ Union until 1985. Previously they were classified as a subspecies of the more common and similar-appearing Western Grebe. The breeding and wintering distribution of these two species overlap throughout their ranges in western North America, and they often flock together throughout the year, even during the breeding season when the two species may nest in mixed colonies.

STATUS AND DISTRIBUTION Little is known about the historical status and distribution of this species because most sightings before 1985 were recorded as “Western Grebes.” Clark’s typically occur in smaller numbers than Western Grebes in the Sierra and elsewhere in California.

West Side. Uncommon migrants and winter residents at foothill reservoirs; similar to Westerns, they breed only at Lake Isabella in the south and at Lake Almanor in the north.

East Side. Fairly common breeders at many of the same lakes and reservoirs as Westerns; uncommon in winter.

TRENDS AND CONSERVATION STATUS See Western Grebe account, above.

CORMORANTS

Family Phalacrocoracidae

Cormorants must leave the water periodically to dry in the sun because their feathers are not fully waterproofed like a duck’s. The structure of cormorant feathers decreases their buoyancy and eases their underwater pursuit of fish. Six of the world’s approximately 30 cormorant species occur in North America. Three species—Brandt’s, Pelagic, and Double-crested Cormorants—occur commonly at bays and protected estuaries of the California coast, but only the Double-crested regularly ventures inland. The family name is derived from Gr. phalakros, bald, and korax, a raven.

Double-crested Cormorant

Phalacrocorax auritus

ORIGIN OF NAMES “Cormorant,” a sea crow, from OF. cormaran; phalacrocorax ( see family account above); L. auritus, eared, for the long, upturned feathers (crests) on their heads that are worn for only a short time during the breeding season.

NATURAL HISTORY With wet wings spread, Double-crested Cormorants perch like awkward black gargoyles on snags or branches of riparian trees. When they swim, their heads and bills are typically cocked upward. Cormorants frequent large bodies of water that provide ample room for their labored takeoffs and small fish, their favored prey. Diving from the water’s surface, they may pursue fish to depths of 5 to 25 feet and can stay submerged for up to 30 seconds. They are equally at home on salt and fresh water, as long as fish are plentiful.

Double-crested Cormorants are colonial breeders that nest on islands or in large trees along lakes and large rivers, often in association with Great Blue Herons, Great Egrets, and other colonial species. In the breeding season, mated cormorants display to each other by stretching up their heads and necks, showing off bright orange throat patches and turquoise blue mouth linings. Both members of the pair participate in building their large nests, up to two feet in diameter and composed of twigs, sticks, and other debris placed in large trees. Nesting in the Sierra generally extends from April until late July. Females usually lay three to four pale blue eggs, and both adults incubate them for about 28 days until hatching. Adults feed and fend for their young until they are independent at about 10 weeks. During the nestling and fledgling period, both adults provide their young with regurgitated fish, crustaceans, frogs, or aquatic insects.

STATUS AND DISTRIBUTION Double-crested Cormorants frequent large lakes, reservoirs, and rivers at low and mid-elevations of the Sierra.

West Side. Fairly common nonbreeding visitors in fall, winter, and spring at most lakes and reservoirs but apparently nest only at Butt Valley Reservoir and Lake Almanor (Plumas County).

East Side. Uncommon but regular visitors except in winter; in some years pairs have nested at Hartson Reservoir, part of the Honey Lake Wildlife Area, but their numbers have fluctuated greatly there; fairly common nonbreeding visitors in spring and fall to other large reservoirs, including Topaz Lake, Crowley Lake, and at Bridgeport Reservoir, where a few pairs nested in the mid-1970s; uncommon but regular nonbreeding visitors to Mono Lake and Sierra Valley in spring and fall.

TRENDS AND CONSERVATION STATUS Once only rare visitors to the Sierra, they now occur regularly in the lower foothills due, at least in part, to construction of numerous reservoirs stocked with fish. Across North America, Double-crested Cormorant populations have increased significantly since the 1970s. A decline in historical persecution and banning of DDT are likely contributors to this increase. Although the species occurs regularly only on a few West Side Sierra Christmas Bird Counts, numbers from those counts have increased approximately four-fold since the 1980s.

PELICANS

Family Pelecanidae

With enormous, pouched bills and massive wingspans, pelicans are among the most spectacular and unmistakable of Sierra birds. Throughout the world there are six species of pelicans but only two, American White Pelicans and Brown Pelicans, occur in North America. White Pelicans occur regularly away from the coast and are likely to be seen in the interior. Brown Pelicans are common visitors to California’s coastal waters and offshore islands but casual visitors to the Sierra. The family name is derived from Gr. pelekon, an ax, a reference to the pecking habits of a similar kind of water bird.

American White Pelican

Pelecanus erythrorhynchos

ORIGIN OF NAMES Pelecanus (see family account above); erythrorhynchos, red-billed, from Gr., from erythros, red, and rhynchos, a bill, as the species’ bill turns bright orange-red in the breeding season.

NATURAL HISTORY Spiraling high above river canyons and mountain passes, large flocks of American White Pelicans cross the Sierra every year, unnoticed by most Sierra visitors. Among the largest of the world’s water birds, they weigh up to 17 pounds and soar on 9-foot wingspans. From late winter until after the eggs are laid, adult males and females display a thin, horny plate on their upper bill. The lower halves of their unique bills are equipped with naked skin pouches that can hold up to three gallons of water and fish when expanded. After excess water has been expelled from the pouch, the fish are swallowed and temporarily stored in the esophagus; they are never stored or carried in the pouch.

Unlike coastal Brown Pelicans, White Pelicans do not dive from the air to catch fish. Instead, they forage at the surface in shallow water, thrusting their heads and bills forward to scoop up fish in their pouches. Flocks of 20 or more White Pelicans often swim and wade together in shallow water, flapping and splashing to herd fish to nearshore areas where they can be captured more easily. White Pelicans prefer to eat fish, but they also consume crayfish and amphibians. They require long expanses of open water to take flight, their wings and feet beating noisily against the water. When at last underway, flocks of White Pelicans fly with grace and agility, climbing to lofty heights and maneuvering together, flapping a few times then soaring in long lines that weave up and down together. When sun flashes across their backs and wings, they suddenly disappear and reappear, as flocks bank in unison.

STATUS AND DISTRIBUTION White Pelicans do not breed in the Sierra regularly, but migrants pass over in spring (early March through May) and fall (early August to early November) in transit between the Central Valley and Great Basin breeding lakes and marshlands. However, not all birds make unidirectional flights; one individual equipped with a radio transmitter at Stillwater National Wildlife Refuge, Nevada, made 7 round trips to the Central Valley (14 crossings of the Sierra) in 1996, probably as part of a nonbreeding flock (Yates 1999).

West Side. Uncommon but regularly observed crossing the Sierra, usually following river drainages, perhaps because they offer reliable navigational signposts and steep canyon walls provide updrafts to assist their flight; migrant flocks might be seen over the American, Feather, and Yuba River drainages, and above Yosemite Valley; fairly common nonbreeding visitors to Lake Isabella and Lake Almanor, Antelope Lake (Plumas County), and other larger northern Sierra reservoirs; regular in winter at Lake Success and Lake Isabella.

East Side. Fairly common during both eastward and westward migrations and when they stop to rest and forage at East Side water bodies from March until May, and a few nonbreeding birds may remain until September; common visitors to Sierra Valley marshes, Lake Tahoe, and such large reservoirs as Crowley Lake, Bridgeport Reservoir, and June Lake; in 1976 close to 2,000 pelicans nested at Honey Lake for the first time, but they have not attempted breeding there since; recorded as far south as Lake Tinemaha in the Owens Valley.

TRENDS AND CONSERVATION STATUS At the turn of the century, White Pelicans nested at large lakes the length of California from the Klamath Basin, through the Central Valley, to the Salton Sea. Today California’s breeding population is restricted to islands at Clear Lake and Tulelake National Wildlife Refuges, near the Oregon border. The largest breeding colony near the Sierra is at Pyramid Lake, north of Reno. White Pelicans have experienced long-term declines in their statewide breeding population due to destruction of their island nesting colonies by inundation or land bridges that permit humans and other predators to disturb their breeding colonies. However, on a continental basis, Breeding Bird Survey data show a steady increase since the 1960s.

HERONS AND RELATIVES

Family Ardeidae

These long-legged waders have long necks that extend their reach and sharp, pointed bills for spearing and grasping prey. They are the only North American birds, other than Western and Clark’s Grebes, having neck mechanisms that permit sudden, spearlike head thrusts toward their prey. Although they may appear awkward while landing or taking off, all members of this family exhibit strong, graceful flight. Bitterns, herons, and egrets can be recognized in flight by their folded necks and long legs trailing behind.

Female herons and egrets usually lay three to five greenish-blue, unmarked eggs (except for bitterns, which lay reddish-brown eggs), and both parents incubate them for about 25 to 30 days before they hatch. The young leave their nests one to two weeks after hatching and are tended by both parents for an unknown period thereafter. This large family includes 63 species that occur worldwide except for the Arctic, Antarctic, and some oceanic islands; 6 species occur regularly in the Sierra. Breeding plumages of most male and female herons and egrets are adorned with plumes on their lower rumps or bright colors on their bare facial skin. Aside from Great Blue Herons, most species are rare above the foothills on both slopes. The family name is derived from L. ardea, a heron.

American Bittern

Botaurus lentiginosus

ORIGIN OF NAMES Named for its call, “bittern” from Fr. butor, which derives from L. butire, meaning to “boom like a bittern”; called butorius because its calls resemble the bellowing of a bull; L. lentiginosus, freckled, referring to spotting of the species’ plumage.

NATURAL HISTORY The combination of cryptic earth tones, blacks, and whites of the American Bittern’s plumage provides a perfect camouflage against a backdrop of cattails or bulrushes. Freezing with heads and necks pointed skyward aligning their vertical throat stripes with surrounding vegetation, they stand motionless until the source of their alarm has passed. Usually solitary, they rely on stealth to capture aquatic insects, amphibians, crayfish, fish, and small mammals. American Bitterns typically remain hidden in marsh vegetation, where they communicate by means of resounding, ventriloquial calls which Ralph Hoffmann (1927) has described as “either wooden, like to blows of a mallet on a stake, or liquid like the gurgling of a pump.” They inhabit shallow wetlands dominated by tall, emergent vegetation near lakeshores, ponds, meadows, and canals in agricultural areas.

Their nesting season extends from late March to late August, with a peak in May and June. Usually solitary breeders, American Bitterns sometimes nest in groups with one male guarding several females within one large territory, suggesting that at least some males may be polygynous. Females alone select nest sites and build nests: large platforms of matted aquatic vegetation, over water, in tall, dense cover.

STATUS AND DISTRIBUTION American Bitterns are uncommon residents and nesters in isolated foothill wetlands of the Sierra.

West Side. Formerly uncommon residents of marshes near Lake Isabella; rare and infrequent visitors and probable nesters at foothill marshes elsewhere on the west slope; a few spring and fall migrants have been found at mid- and high-elevation marshes near tree line.

East Side. Common spring and summer visitors and suspected nesters in Sierra Valley; extirpated as a breeding species from many former areas in the eastern Sierra, including Lake Tahoe and Mono Basin; uncommon spring and fall migrants in near Tahoe Keys (south Lake Tahoe), but breeding has not been confirmed; since the 1970s, only casual migrants have been observed in dense marshlands near Mono Lake and the upper Owens River, with only one record from those areas since the early 1990s.

TRENDS AND CONSERVATION STATUS The secretive nature of this bird makes monitoring populations difficult, but data from U.S. Breeding Bird Survey and Christmas Bird Counts suggest long-term steady declines. California Christmas Bird Counts also show declines since the 1970s, with the most dramatic trends seen in coastal areas.

Great Blue Heron

Ardea herodias

ORIGIN OF NAMES “Great Blue” refers to large size and overall coloration; “heron” is from OF. hairon; ardea (see family account above); Gr. herodias, heron.

NATURAL HISTORY Few Sierra birds are as majestic as North America’s largest heron. Standing fully four feet tall, with wingspans of seven feet, Great Blue Herons dwarf most other water birds of the region. Although typically silent, Great Blues utter deep, harsh croaks when startled or when interacting with others of their species. They are solitary feeders and forage both night and day but are most active around dusk and dawn. They stalk fish, frogs, crayfish, and aquatic insects in the shallow margins of lakes, ponds, marshes, and rivers where fish and aquatic prey are plentiful. In winter and spring, Great Blues hunt for mice, gophers, and other small animals in wet pastures, recently irrigated agricultural fields, and even dry land. When hunting, they may stand motionless for several minutes or inch forward stealthily, with necks outstretched. Suddenly they strike, grasping small prey in their bills or spearing larger animals. Strong fliers, these birds may travel up to 10 miles from their nests to find food.

Great Blues nest colonially, and more than 100 nests may be present in large rookeries, which are often shared with Great Egrets and sometimes with Snowy Egrets, Black-crowned Night-Herons, or Double-crested Cormorants. In the Sierra most rookeries are in the tops of tall riparian trees that are relatively protected from wind and human disturbance. The same trees may be used year after year until they fall or are removed by humans. Less commonly, Great Blues nest on cliffs or amid marsh vegetation. Adults usually arrive at their nesting colonies in February, and nesting activities often extend through July. Nesting platforms may exceed three feet in diameter and are built from large sticks and lined with smaller twigs and grasses. Both parents tend the young, and one adult is almost always present at the nest for the first few weeks. During the nestling period, the hoarse, monotonous clacking calls of juveniles resonate for long distances.

STATUS AND DISTRIBUTION This successful, adaptable, and widespread species is the most common Sierra heron and the only one regularly seen above the foothills.

West Side. Fairly common year-round near lakes, reservoirs, and rivers up to about 4,000 feet in the central Sierra; most breed in lowlands of the Central Valley, but a few rookeries have been observed along lower portions of the North and South Forks of the Kern River, South Fork Kaweah River, lower American River, and Yuba River; the highest elevation west-slope breeding colonies are at Lake Almanor (about 4,560 feet); postbreeding birds sometimes follow river drainages into the high Sierra to Subalpine lakes and meadows above 8,000 feet in late summer and fall.

East Side. Fairly common year-round residents, the cold-hardy Great Blues outnumber all other herons and egrets; they nested, at least formerly, near Honey Lake, Boca Reservoir, and in the Lake Tahoe Basin, and one colony has been active since the 1990s in Long Valley (Mono County); nonbreeding Great Blues can often be found at Sierra Valley, Honey Lake, Lake Tahoe, Bridgeport Reservoir, Mono Basin, Crowley Lake, and along the upper Owens River.

Great Egret

Ardea alba

ORIGIN OF NAMES “Egret” from OF. egrette (aigrette), egret, from Gr. word for “heron” with diminutive -ette added; L. ardea, heron; L. alba, white.

NATURAL HISTORY Great Egrets are one of the most striking and conspicuous members of their family in North America. Their brilliant white plumage and large size (slightly smaller than Great Blue Herons) make Great Egrets stand out in any landscape. They forage along the edges of marshes, lakes, canals, and slow-moving streams as well as irrigated croplands and pastures, where they often associate with Great Blue Herons and Snowy Egrets. Standing motionless or stalking slowly, they suddenly strike their prey with daggerlike bills. Their diverse diet includes fish, amphibians, reptiles, snails, crustaceans, insects, small mammals, and such small birds as rails (including Threatened Black Rails) in coastal areas.

In the breeding season, extravagant plumes grace the plumage of both males and females. Just prior to breeding, each bird grows 40 to 50 plumes that extend from their backs to well below their tails. They fan these plumes while performing elaborate courtship displays; plumes are lost soon after breeding. In the Sierra, Great Egrets usually nest in tall riparian trees near water, often in association with Great Blue Herons and Double-crested Cormorants. Both parents collect large sticks and construct large platform nests up to two feet in diameter. Young hatch with a soft covering of down but begin to grow feathers within a week. They remain in their nests for about three weeks and then begin taking experimental flights to nearby branches. Both adults feed and tend the young for about two months until they gain independence.

STATUS AND DISTRIBUTION Great Egrets are mostly confined to low elevations on both sides of the Sierra.

West Side. Fairly common at foothill wetlands and rare visitors to lakes and reservoirs up to the Lower Conifer zone; in fall, a few individuals have been spotted at Subalpine meadows such as Tuolumne Meadows (about 8,600 feet) in Yosemite National Park, and near the Sierra crest above the North Fork American River; uncommon year-round residents at Lake Almanor in the north and at Lake Isabella in the south, where they are also irregular nesters.

East Side. Uncommon spring and fall migrants, they apparently do not remain to nest; each year migrants visit marshlands in Sierra Valley, Bridgeport Valley, Mono Lake, Lake Tahoe, and the upper Owens River but seldom in large numbers; casual to rare in winter.

TRENDS AND CONSERVATION STATUS The millinery trade reached its heyday in the late 1800s, as feathers were in great demand for women’s hats and garments. Plume hunters targeted Great and Snowy Egrets because of their large size, abundance, and long plumes (called “aigrettes” in the millinery trade). In less than 20 years, Great and Snowy Egrets were nearly exterminated across a large swath of North America, including California. None were seen in the state for many years, and both species were considered rare until the 1920s. Great Egrets became a symbol for a growing conservation movement, led by the National Audubon Society and the American Ornithologists’ Union, aimed to educate men not to shoot egrets and women not to adorn their hats with aigrettes. By the early 1900s public opinion and fashions had changed, and these egrets and most other native birds received protection under the federal Migratory Bird Treaty Act. With strict protection Great Egret populations have largely recovered and the species is now common across most of its former range, including California. Like all colonially nesting birds, Great Egrets are susceptible to human disturbance around their nesting colonies. They may be increasing in winter in the western foothills based on results from some lower elevation West Side Christmas Bird Counts.

Snowy Egret

Egretta thula

ORIGIN OF NAMES “Snowy” for the species’ bright white plumage; egretta from OF. aigrette, egret; thula, a Chilean name for this bird.

NATURAL HISTORY Some birders call Snowy Egrets “golden slippers” because of their bright yellow feet. Similar to Great Egrets, these birds sport brilliant white plumage but they are small and dainty compared with their more common relatives. Snowy Egrets frequent shallow waters along the edges of marshes, slow-moving streams, and canals. They also forage in irrigated fields and pastures with other egrets and herons. They are more active foragers than other members of their family in the Sierra, and often dash through shallow water using their golden slippers and wings to flush unsuspecting prey. Like other egrets and herons, they also stand motionless or stalk slowly while searching for preferred foods, including small fish, crustaceans, and large aquatic insects. On occasion they also consume amphibians, reptiles, worms, and small mammals.

STATUS AND DISTRIBUTION Common residents of the Central Valley, Snowy Egrets rarely venture into the Sierra.

West Side. Rare and mostly confined to the lowlands below about 1,000 feet, Snowy Egrets have been observed at Lake Almanor, Lake Isabella, Lake Wildwood (Nevada County), and in Yosemite Valley in spring, summer, and fall; a single bird was observed in late May at Tuolumne Meadows (about 8,600 feet) in Yosemite National Park, but there are few other records above 4,000 feet; rare to casual in winter at lowest elevations.

East Side. Rare spring and fall visitors to east side marshlands, with individual records from Sierra Valley, Boca Reservoir, Honey Lake, Lake Tahoe, Mono Basin, Grant Lake (Mono County), and Crowley Lake; a pair nested at Mono Lake in the early 1990s, but there are apparently no other nesting records; accidental in winter.

TRENDS AND CONSERVATION STATUS See Great Egret account, above.

Green Heron

Butorides virescens

ORIGIN OF NAMES “Green” for the dark green upperparts of adults; L. butorides probably means “bittern-like”; L. virescens, becoming green.

NATURAL HISTORY Perched on a log or branch at water’s edge with their necks folded, these chunky, crow-sized birds may be difficult to recognize as herons. Green Herons inhabit secluded lakes, ponds, marshes, and slow-moving foothill rivers and creeks that are shaded by riparian trees and often clogged with floating wood. They nest and roost in willows, oaks, and other trees and prefer to forage in their shade. Extremely agile, they climb among wooded tangles while stalking small fish, crustaceans, insects, and rarely small mammals. They also wade or stand in shallow water, much like Great Blue Herons. Sometimes Green Herons hunt from logs or streambanks and may even dive headfirst at their prey. They are known to fish by placing “lures” such as feathers on the water’s surface, thereby attracting their prey close enough to catch.

Unlike most other members of their family, Green Heron pairs are solitary while nesting. In the Sierra their nesting season extends from early March until late June. Both members of mated pairs participate in building nests, which can range from a simple pile of sticks to a more elaborate, woven structure that is reused in successive years. Their nests, up to 18 inches in diameter, are positioned in shrubs and trees up to about 50 feet above the ground. Both parents tend the young until they can fly, about 25 days after hatching.

STATUS AND DISTRIBUTION Green Herons are mostly confined to low elevations of the Sierra.

West Side. Uncommon year-round residents in the lower foothills, usually below about 3,000 feet; rare at higher elevations although Sequoia Lake at 5,300 feet (Fresno County) has two records; possibly present at all seasons except winter, and they are suspected nesters at Lake Isabella, Yosemite Valley, and Lake Almanor.

East Side. Rare spring and summer migrants through the Mono Basin, June Lake, and riparian habitats, with most records from March through June; a few records from Sierra Valley and from Carson Valley.

Black-crowned Night-Heron

Nycticorax nycticorax

ORIGIN OF NAMES “Black-crowned” to distinguish it from the similar Yellow-crowned Night-Heron (Nyctanassa violacea); nycticorax, a night bird, from Gr. nyctos, night, and corax, a crow.

NATURAL HISTORY As their name suggests, Black-crowned Night-Herons forage primarily at night and in the twilight hours. When feeding young, however, they are active all day because food sources may be many miles from their nesting sites. When not nesting, they spend most diurnal hours in large, colonial roosts in dense riparian trees and shrubs or marsh vegetation. Night-Herons forage and roost along densely vegetated lake and pond margins; wet, brushy meadows; and riparian vegetation lining slow-moving streams and canals. They are attracted to fish hatcheries, which provide an abundant source of easily captured prey. Opportunistic foragers, they consume a varied diet of small fishes, snakes, crayfish, and other crustaceans, aquatic insects, and other invertebrates. Night-Herons are also voracious predators of birds’ eggs and nestlings, especially those of colonial-nesting species such as other herons and egrets, White-faced Ibis, and Tricolored Blackbirds. Night-Herons also consume ducks’ eggs and nestlings and may destroy entire clutches of Wood Ducks, Mallards, and Cinnamon Teal.

Highly gregarious, Night-Herons nest in dense rookeries with members of their own species as well as other herons and egrets. Both members of mated pairs participate in building their large nests, which average about 2 feet in diameter and 18 inches in depth. Nests are built from locally available materials including sticks in riparian areas or cattail and bulrush thatch in marsh habitats. In the Sierra their courtship behavior begins in February and nesting continues into July. The young remain in their nests for at least two or three weeks and are tended by both parents. Juveniles attain complete feathering within about a month and can fly within about six weeks. Gregarious even outside the breeding season, large day roosts of many birds are found in marshes and dense riparian areas.

STATUS AND DISTRIBUTION Black-Crowned Night-Herons are mostly confined to low elevations on both sides of the Sierra.

West Side. Rare to locally uncommon in wetlands within annual grassland, foothill chaparral, and oak woodland habitats up to about 1,000 feet in the Yosemite region and somewhat higher in the southern Sierra, as at Lake Isabella (about 2,600 feet), where they reside year-round; casual at Lake Almanor and at Subalpine lakes and marshes in the Yosemite region up to about 9,000 feet in late summer and fall; the probable Sierra altitude record-holder was at Saddlebag Lake near Tioga Pass, just outside Yosemite National Park (10,200 feet) in October 2007.

East Side. Fairly common from March until October in marshlands of Sierra Valley, Honey Lake, and rare visitors to Lake Tahoe; locally common farther south, with colonies at Mono Lake and Laurel Pond (Mono County); they may also nest at Bridgeport Reservoir, Crowley Lake, and in dense emergent marshlands along Hot Creek and the upper Owens River (Mono and Inyo Counties).

IBIS

Family Threskiornithidae

This family includes both the ibises and spoonbills, representing more than 30 species worldwide; five of these exist in North America but only one, the White-faced Ibis, regularly occurs in the Sierra. White-faced Ibis can be distinguished from most other wading birds by their long, decurved bills, distinctive glossy plumage, and highly gregarious habits in all seasons. The family name is derived from Gr. threskiornis, a sacred bird.

White-faced Ibis

Plegadis chihi

ORIGIN OF NAMES “White-faced” for the white facial feathers of breeding birds; “ibis” is an Egyptian name taken from Sacred Ibis (Plegadis aethiopicus) that was mummified and depicted on tombs; Gr. plegas, sickle, for curved the bill; chihi is probably a native South American name for this bird.

NATURAL HISTORY White-faced Ibis are strong fliers that depend on ever-changing seasonal wetlands, requiring them to constantly move in search of productive feeding areas and secure nesting sites. They forage by probing their long, decurved bills into shallow water or moist soil searching for aquatic and moist-soil insects, crustaceans, and earthworms. They prefer shallow marshes with islands of cattails or tules but also forage in upland soils, including agricultural fields—especially rice.

While males are slightly larger, both sexes have identical plumage and display beautiful metallic green and bronze hues in the breeding season. A thin white border of feathers surrounds their bills, hence their common name “white-faced.” These white markings, as well as their iridescent plumage highlights, are lost when they molt into winter plumage.

These long-legged waders emit soft grunts and oink calls at their nesting colonies or when flushed. They fly in long, undulating lines, constantly shifting positions with strong, rapid wingbeats and alternating glides. They normally fly fairly close to the ground, but flocks also climb to great heights before making dramatic dives—pulling up just before hitting the ground.

In California, ibis initiate nesting in shallow, freshwater marshes from mid-April until late May. Both sexes participate in nest building, bending stems of partially submerged cattails or bulrushes over to form a woven platform just above the water’s surface. Nests may be hard to see, hidden deep within dense patches of emergent vegetation, but their colonies are obvious with ceaseless traffic of dark birds entering and leaving the marsh. Nesting colonies move to new sites when water levels or other conditions change. Females lay three to four greenish or bluish eggs, marked with dark spots or scrawls that both sexes incubate for about 22 days. By about three weeks after hatching, fledglings can move a short distance to acquire food from their parents, and by five weeks the adults start leading the young on a series of short flights through the colony, feeding them at each stop.

STATUS AND DISTRIBUTION White-faced Ibis are now common residents of the Central Valley (see “Trends and Conservation Status,” below), and they occasionally stray into the Sierra.

West Side. Rare postbreeding wanderers can be seen at low-elevation marshes; regular but uncommon in the Kern River Valley in spring and fall.

East Side. Nesting has been observed at a few isolated marshes north of Truckee and intermittently at Honey Lake since the mid-1970s, with the largest colony at Sierra Valley (hundreds of pairs in wet years but absent during dry years); they wander widely during migration and after the nesting season and might be seen in large wetlands or agricultural areas; accidental in winter.

TRENDS AND CONSERVATION STATUS Formerly common nesters the length of California, Whitefaced Ibis were reduced to very low numbers by the 1960s and were included on the list of California Bird Species of Special Concern in 1972. The principal cause of their dramatic decline was draining of Central Valley and coastal marshes; eggshell thinning due to DDT was also implicated. In the late 1970s ibis began returning to the state in numbers, possibly in response to inundation of historical marsh nesting areas at the Great Salt Lake. Their breeding population has increased steadily since. The species was rarely recorded on Central Valley Christmas Bird Counts in the 1970s and 1980s before numbers began to grow exponentially from the early 1990s and reach a plateau in recent years. For example, the species was nearly unseen in the 1980s at Lake Almanor, where it is now common in mid- to late summer. Flocks numbering in the tens of thousands now roam marshlands and agricultural fields of the Central Valley and northeastern California to the extent that in 2008 they were removed from California’s list of Bird Species of Special Concern. Increases in Central Valley managed wetlands and winter flooding of rice fields may have contributed to the recovery of the species in California.

NEW WORLD VULTURES

Family Cathartidae

New World vultures are large scavengers with long, broad wings enabling them to soar great distances in search of carcasses. These carrion-eaters have extraordinary vision and can find dying or recently dead animals from high in the air. They often feed by thrusting their featherless heads into the body cavities of rotting animals, so baldness avoids the problem of chronically soiled head feathers. Of the seven species in this family, Turkey Vultures are fairly common to abundant in the Sierra, and California Condors historically nested there. The family name is derived from Gr. kathartes, a cleanser or purifier, for their habit of cleaning up carcasses.

Turkey Vulture

Cathartes aura

ORIGIN OF NAMES “Turkey” for the species’ resemblance to the similarly naked-headed Wild Turkey; “vulture” from OL. vuellere, to pluck or tear; cathartes (see family account above); aura may be related to a South American Indian name for the bird.

NATURAL HISTORY Spiraling almost effortlessly on warm updrafts, Turkey Vultures soar gracefully over open grasslands, chaparral, and oak-lined canyons of the Sierra foothills. Their long wings, slightly smaller than those of Golden Eagles, are held in a flattened “V” with grayish flight feathers spread almost like fingers. Exceptionally light for their size, they wobble unsteadily from side to side, only rarely flapping their wings. So finely tuned are their abilities that vultures may soar for many hours simply by moving from updraft to updraft.

Vultures are ever on the lookout for carrion, which they identify both visually and by detecting drifting molecules of decay. Their keen sense of smell, one of the most refined of all birds, is so acute that Turkey Vultures can locate carrion buried under leaves in forests or dead animals as small as insects. They usually forage individually, but several may gather to feast communally on an especially desirable carcass, where they waste no energy fighting among themselves. While Turkey Vultures are capable of subduing very small prey, poet Kathleen Lynch (2000) has it pretty much right:

Of all the birds

watching from winter-stripped

trees. Vultures are

kindest, killing

nothing.

Dependent on unpredictable and sparsely distributed carrion, vultures are the undisputed masters at conserving energy between meals. A sunny morning will find them perched with spread wings, warming up without using calories. Raising and lowering the ruff of feathers around their neck is another means of efficiently regulating body temperature. Vultures expend extra energy during courtship flights, when determined males may spend up to an entire day flying close behind a prospective mate. In California breeding activities usually begin in mid-April, when pairs seek out dark recesses in cliffs or rocky slopes. These can sometimes be found by smell, as the stench of regurgitated carrion at nest sites is almost unbearable. Both parents help incubate two eggs that hatch in about a month. It takes 70 to 80 days before the young birds leave the nest.

STATUS AND DISTRIBUTION Small numbers of Turkey Vultures reside year-round in northern California, but most migrate south to spend the winter in more productive foraging grounds from central California to northern South America. Fall migration can be extremely impressive when groups of hundreds or even thousands of birds float together over Sierra ridgetops and river canyons. Recent studies suggest the foothills of the West Side comprise a major vulture migratory route drawing birds from the Pacific Northwest. Especially high numbers have been recorded in the South Fork Kern River Valley, where nearly 30,000 are counted each fall, but thousands of migrants can also be seen over most Sierra river canyons from late September until mid-October.

West Side. Fairly common winter residents of the foothills, their numbers increase dramatically from early March until late April, when migrants and breeding birds return to the region; common from early May until mid-September in oak savanna and annual grasslands below the Lower Conifer zone, especially where there is a mix of intact forest and open grazing land; uncommon up to the Upper Conifer zone and rare up to the Subalpine zone in late summer and early fall.

East Side. Fairly common in both spring (mostly April) and fall (mostly September) migration; uncommon during summer and rarely nest; casual in winter.

California Condor

Gymnogyps californianus

ORIGIN OF NAMES “Condor” is a Spanish rendering of an indigenous Peruvian name for these birds; Gr. gymnos, naked, and gyps, vulture; L. californianus, of California.

NATURAL HISTORY California Condors once soared over open expanses of western North America searching for decaying carcasses provided in abundance by vast herds of bison, elk, deer, and pronghorn. Prior to European colonization, they occurred from British Columbia to Baja California, but shooting, lead poisoning, nest disturbance, decline in food supply, and other human intrusions have caused dramatic declines, almost to the point of extinction (see “Trends and Conservation Status,” below).

With nine-foot wingspans, California Condors are the largest land birds in North America. These giants routinely make round trips of 70 miles or more between roosting and feeding sites. They always feed on the ground in open areas such as grasslands and oak savanna, where there is sufficient space and suitable air currents for their labored landings and takeoffs. Both fresh and decomposing carcasses of cattle, sheep, deer, and ground squirrels are the mainstays of their diet. Lacking a keen sense of smell, condors locate the majority of their food by watching other scavengers such as Turkey Vultures.

Condor reproductive rates are low and a successful pair will generally hatch only one egg every other year. Their chicks take about 100 days to gain adult size but do not fledge for another two months. They depend on the adults for food and protection for at least another six months, an extraordinarily long period of dependency. Nests are simple depressions on cliff ledges or potholes in caves, although in the Sierra they are known to have nested in cavities in giant sequoias. Female condors do not breed until at least their sixth year, and mated pairs often remain together for long periods. Prior to their first mating, immature birds, either singly or in groups, will spend a year or more visiting and becoming familiar with the foraging range and nesting territories of the adult population.

STATUS AND DISTRIBUTION According to Grinnell and Miller (1944), California Condors were “formerly (within historic times and up to about 1870) common throughout that portion of the State lying west of the Great Basin and desert territories, and north from the Mexican line to the Oregon line.” These authors noted that condors were known from the foothills of Kern, Tulare, Fresno, Madera, and Tehama Counties as well as the Owens Valley, mainly below 6,000 feet.

West Side. The last known nesting pair of condors in the Sierra was recorded in 1984 nesting in a giant sequoia in Sequoia National Forest (Tulare County); as of 2011, there were no records of wild condors present in the Sierra, although rugged and remote areas in the southern Sierra may be prime candidates for reintroduction efforts in the future and are the likely destinations of wandering birds from current reintroduction efforts in the mountains of southern California. There have been a few records from the Kern River Canyon in recent years.

East Side. No modern records.

TRENDS AND CONSERVATION STATUS By 1950 the global population of California Condors numbered only about 150, and the species was listed as Endangered by the U.S. Fish and Wildlife Service in 1967 and by California in 1971. Their numbers dropped to around 15 birds by 1987, when all remaining wild birds were captured and taken into captive breeding programs to prevent the species’ extinction. Since 1988, captive-bred birds have been produced and, as of 2010, more than 380 had been released into suitable habitat areas in coastal southern California, Utah, Arizona, and Baja California. These releases have met with variable success, with relatively high mortalities of both adult and juvenile birds due to the failures of captive-reared birds to exhibit wild behaviors and from consumption of lead fragments from bullets in deer and other game. Establishment of self-sustaining, wild populations may not be realistic until the problem of lead contamination from bullet fragments can be addressed on a range-wide basis.

OSPREY

Family Pandionidae

In recent decades Ospreys were considered a subfamily of the family Accipitridae, along with hawks, kites, and eagles. However, they are again considered a distinct family, represented by only a single species. This is supported by genetic studies and physical characteristics including having toes of equal length and rounded, rather than grooved, talons. Ospreys and owls are the only raptors with reversible outer toes, allowing them to grasp prey with two toes in front and two behind. The family name is thought to be derived from Pandion, a king of Greek mythology whose two daughters were turned into birds; this name may also derive from L. pan, all; and L. dio, god.

Osprey

Pandion haliaetus

ORIGIN OF NAMES “Osprey” from L. ossifraga, bone breaker, for a European vulture, but how the name got transferred to this fish-eating bird is unknown; pandion (see family account above); haliaetus, a sea eagle, from Gr. hals, sea; aetos, eagle.

NATURAL HISTORY Among the world’s most widespread birds, Ospreys occur on six continents, although they are rarely common in any single area. Their favored habitats are large lakes, reservoirs, rivers, and coastal areas with clear water and ample fish, and they are seldom observed away from such sites. The commonly used term “fish eagle” is appropriate, as they are the only North American raptor dependent almost solely on fish. They watch for fish from perches on rock outcrops or snags or hunt by flying low over the water. They prey on many types of fish but prefer those 6 to 12 inches long that school near the surface. If fish are not available, they may take other prey, such as turtles, snakes, frogs, shorebirds, and ducks on rare occasions.

Ospreys capture fish by diving headfirst, swinging their feet forward past their heads and extending their wings back behind their bodies just before striking the water. Almost instantly they surge back out of the water with one powerful beat of their wings. Their long toes have tiny spikes that help them grip and subdue slippery prey. They usually fly back to a favorite perch to eat, holding the fish tightly with its head pointing forward to reduce air resistance or to prevent theft by other raptors.

In their second year Ospreys may form pair bonds and build a nest, but their first nesting attempt is usually during their third or fourth year (up to five years for some pairs). Elaborate male courtship flights are rewarded with as many as 400 copulations in the three weeks prior to egg-laying. Nests are huge, bulky structures built mostly of sticks and other debris by males, with the female lining the inside with grasses or other soft material. They are constructed on snags, on cliff faces, telephone poles, high tension towers, and other artificial structures—always near large rivers or lakes. Nests are repaired and added to each year, and the same pair (or later generations) might use the same nest for decades; nests may eventually grow to huge proportions—more than 6 feet wide and 12 feet deep. Two to three large whitish eggs are incubated for just over a month, mostly by the female. Nestlings remain in the nests for about 40 days and are capable of flight in about 2 months. Canada Geese, which begin nesting earlier than Ospreys, sometimes take over Osprey nests, which results in fierce battles after Ospreys return to discover the intruders.

STATUS AND DISTRIBUTION Primarily summer residents though many remain in California through the winter, with the largest numbers along the coast and in the southern half of the state. Breeding pairs are scattered throughout the Sierra.

West Side. Nesting pairs occur near most of the large lakes and reservoirs and many large rivers; representative breeding locations include Lake Almanor, Lake Oroville, New Bullards Bar Reservoir (Yuba County), Bass Lake (Madera County), and Lake Isabella, where fairly common. During both spring and fall migrations, they are more widespread and might be observed over any habitat type below the Upper Conifer zone, though rarely far from water.

East Side. Uncommon and scattered; several pairs nest each year on tufa towers at Mono Lake, flying to distant lakes to find fish; they also breed in the Tahoe Basin and other lakes in Mono County; breeding season observations in Alpine and Inyo Counties.

TRENDS AND CONSERVATION STATUS Common until the second half of the 20th century, the introduction of DDT and other chemicals led to a dramatic decline in Osprey populations throughout their North American range. Since DDT was banned in the 1970s, Osprey numbers have steadily increased. The creation of numerous reservoirs and artificial nesting structures facilitated an increase in population and expansion of their range in the Sierra.

HAWKS AND RELATIVES

Family Accipitridae

All species in this large and diverse family are daytime predators with keen eyesight, sharp talons, and hooked beaks for dismembering and devouring prey. Like owls, they often consume whole animals and digest them in their highly acidic stomachs. Fur, feathers, and bones are then passed on to the gizzard (a muscular stomach), compressed into pellets, and regurgitated. These pellets, or castings, provide useful information about diets. Females are larger than males, but most species do not show noticeable plumage differences between the sexes.

Female kites and harriers lay four to six eggs, while most hawks only lay two to four eggs. All Sierra members of this family have buffy-white eggs that are variably splotched with brownish or maroon streaks. Female kites, harriers, and hawks incubate the eggs for 25 to 35 days, with occasional help from the males, who provision food to the females and nestlings. Eagles only lay two eggs, which both parents incubate for 35 to 45 days. All raptors begin incubating their eggs after the first one is laid (unlike waterfowl and many other birds), so they hatch asynchronously and the youngest nestlings may starve or be eaten by their older siblings if food is in short supply. Immatures require at least one and, in some species, two or more years to achieve adult plumage. Golden and Bald Eagles take four or five years, respectively, to reach maturity. Worldwide this family is represented by about 205 living species, and 13 of these occur annually in the Sierra. The family name is derived from L. accipiter, to grasp or seize.

White-tailed Kite

Elanus leucurus

ORIGIN OF NAMES “Kite” may derive from an Indo-European root meaning to shoot or move quickly; elanus, from Gr. elauno, to harass or drive forward; leucurus, from Gr. leukos, white, and oura, tail.

NATURAL HISTORY Attired in bold shades of white, gray, and black, hovering White-tailed Kites grace open landscapes of the Sierra foothills. Some long-term residents call them “Angel Hawks” for this behavior. From hovering positions 20 to 100 feet above fields and pastures, kites scan intently for the movements of meadow voles. Nearly their entire diet consists of these small rodents, making kites an effective regulator of rodent populations. When voles or other prey are spotted, kites have the peculiar habit of making slow, vertical descents by pulling their wings up into a steep “V” and parachuting gently downward feet-first. It’s a surprisingly effective strategy, with capture rates approaching 50 percent. This degree of specialization has its drawbacks, however, for kite populations fluctuate broadly in close synchrony with the ebb and flow of vole populations.

Kites take advantage of peak rodent numbers in late March and April to ensure the best chance of raising their young in the face of a fluctuating food supply. By rearing clutches of four or five eggs, and double-brooding in good years, they end up having one of the highest reproductive success rates of all local hawks. Pairs build nests among the dense outer foliage of trees, exceedingly well concealed from below but open to the sky above so they can scan for approaching danger. Females incubate the eggs for about 30 days while the males provide food for mates and young throughout the entire nesting period, sometimes transferring food to the female in midair exchanges. The young attain flight in about 40 days, but they return to the nest to receive handouts from their parents for up to six months.

STATUS AND DISTRIBUTION Year-round residents that nest below 2,000 feet, White-tailed Kites scarcely make it into the western fringe of the Sierra foothills. They favor wet meadows, grasslands, oak savannas, irrigated pastures, and alfalfa or hay fields, dropping out at elevations where trees start forming a continuous cover. By all accounts, they remain close to water, probably because voles and other prey are most abundant there. They prefer to nest in or near open areas where they can readily hunt. After the breeding season, kites may wander over a wider range, sometimes appearing at higher elevations and on the East Side.

West Side. Uncommon and localized year-round residents below the Lower Conifer zone but casual as high as the Sierra crest, especially in late summer; outside their few known Sierra breeding areas, kites might be seen dispersing high overhead.

East Side. Generally quite rare except for a spate of activity in the mid-1970s, when population numbers were at a high and West Side birds were wandering, probably to avoid a drought when a handful of birds showed up around Reno, Sierra Valley, and Honey Lake in fall with some into winter or were observed in transit elsewhere; other fall and winter records from Honey Lake, Sierra Valley, Mono County, and Owens Valley attest to the ability of this species to disperse widely outside the breeding season; a few spring records from the north end of the Owens Valley are exceptional.

TRENDS AND CONSERVATION STATUS These elegant birds suffered a precipitous decline in the first half of the 20th century at the hands of hunters and egg-fanciers. Fully protected in California in the 1960s, well before the state or federal Endangered Species Acts were passed, kites began a dramatic recovery that lasted well into the 1970s. Their success is a function of their unusually high reproductive rate and ability to tolerate some habitat fragmentation and human disturbance, but their population growth has also been linked to a 40 percent expansion of irrigated agricultural land between 1944 and 1978. Since then, their population may be declining, perhaps as a result of residential and commercial development of former agricultural lands or conversion to more intense agriculture like vineyards and orchards in the Central Valley and Sierra foothills.

Bald Eagle

Haliaeetus leucocephalus

ORIGIN OF NAMES “Bald” for white head color of adults; both Fr. aigle and OE. eagle are derived from L. aquila, eagle; similar to aquilo, the north wind, a symbol of Roman military prowess; haliaeetus, sea eagle, from Gr. hals, sea, and aetos, eagle; leucocephalus, white-headed, from Gr. leukos, white, and kephale, head.

NATURAL HISTORY Bald Eagles are familiar to most people as the country’s national symbol. They are also the second largest bird of prey in North America, after the California Condor, with wingspans exceeding seven feet. They obtain much of their food by scavenging animal carcasses or using their formidable size to steal freshly caught items from other more efficient predators like Ospreys and Great Blue Herons. All types of carrion and prey are consumed, with fish being preferred and forming the bulk of their diet, although they also take many American Coots and waterfowl during the winter. Along Highway 395 in the northeastern Sierra, road-killed deer carcasses are especially preferred and injured waterfowl are pursued in hunting areas in the Central Valley and Sierra foothills. Bald Eagles capture fish and other animals by swooping down from perches or from flight.

For successful nesting, Bald Eagles require sizable bodies of water with dependably productive fisheries, suitable nest sites, and little human disturbance. Recent studies show that younger Bald Eagle pairs are nesting closer to areas of human activity than older pairs, suggesting habituation to human presence. Peak nesting in the Sierra takes place from March to June, and pairs often reuse the same nests for years, gradually building into massive structures. The largest nests in North America have measured up to 18 feet tall and nearly 2 tons in weight. Tall, older trees within half a mile of water are most frequently used, but occasionally nests are built on cliff ledges, especially along the coast. Nests are usually well shaded by foliage or rock overhangs. Nestlings are capable of flight in about 11 weeks but often return to the nest to receive food from the adults for several months after that. Young birds wander until attaining adult plumage at about five years, when they may breed for the first time.

STATUS AND DISTRIBUTION Historically, Bald Eagles probably nested throughout the Sierra. As their population steadily recovers from mid-20th-century lows, their nesting range continues to expand as new sites are occupied each year. From October to March, they can be seen regularly though rarely throughout the Sierra with many at a time occasionally observed at some sites; such large winter gatherings may increase in the future as Sierra populations continue to grow. In the nonbreeding season, they travel great distances over many types of habitats but occur most often near large rivers, lakes, and reservoirs. During the breeding season (April through September), Bald Eagles are still rare in the central and southern portions of the Sierra.

West Side. Fairly common to uncommon, pairs have nested as far south as Tuolumne County but will likely expand further southward in the future; large reservoirs along the full length of the range attract visiting Bald Eagles during the nonbreeding season, creating the possibility that new pairs will become established where conditions are favorable.

East Side. Uncommon in the breeding season, breeding records south to Long Valley (Mono County) with possible breeding further south; fairly common nonbreeding visitors to large bodies of water with plentiful fish.

TRENDS AND CONSERVATION STATUS After World War II, the use of DDT and other organochlorine compounds became widespread as insecticides to control mosquitoes and other insect pests. Breakdown products from these compounds accumulated in Bald Eagles and other birds of prey, causing eggshell thinning and almost complete reproductive failure in many species. In addition, Bald Eagle nests have been abandoned due to disturbances from nearby human activities. For these reasons the U.S. Fish and Wildlife Service and the California Department of Fish and Game listed the species as Endangered in 1978. A ban on use of DDT in the late 1970s, and greater protection of known nesting territories by federal and state agencies, allowed Bald Eagles to dramatically increase their population and expand their range in California and throughout the United States. Because of this recovery, the U.S. Fish and Wildlife Service reclassified Bald Eagles as Threatened in 1995 and delisted them entirely in 2007. They are still listed as Endangered and considered Fully Protected by California and are also protected under the federal Bald Eagle and Golden Eagle Protection Act. Historically huge Sierra salmon runs are now a thing of the past due to dam construction and water diversions, and this may limit the extent of the Bald Eagle’s recovery in this region, although construction of reservoirs has undoubtedly benefited the species.

Northern Harrier

Circus cyaneus

ORIGIN OF NAMES “Harrier” from “hen-harrier,” a British name for the species’ habit of harrying poultry; circus from Gr. kirkos, a hawk, refers to the species’ circling flight; L. cyaneus, blue, for the male’s grayish-blue upperparts.

NATURAL HISTORY One often sees these low-flying hawks hunting low over grasslands and marshes of the Sierra Nevada. Northern Harriers have an owl-like facial disk that funnels sound into large ear openings. While not hunting like owls in the dark, they do work very close to the ground in a “low patrol” fashion, where their excellent hearing helps them locate prey, even in dense cover. These hunting flights can be quite dramatic, as harriers hunt almost solely through active flight: “It oftenest moves in a huge zigzag course, quartering its territory like a hunting dog” (Dawson 1923). When prey is detected, the harrier may suddenly stop, perform an acrobatic downward turn, and plunge suddenly onto an unsuspecting vole, bird, or reptile.

While many breeding pairs are monogamous, some male harriers maintain harems of two to five females, a rare behavior among hawks. In the Sierra the breeding season begins in late March or early April, when males are in frequent flight, performing energetic roller-coaster courtship displays that may include dozens of U-shaped dips. Both sexes carry grasses and other materials, but the females do the nest building alone. During incubation, males bring a steady supply of skinned and beheaded prey to the female, with the exchanges frequently occurring in flight with the male dropping the item and the female snatching it in midair. Their nests are well hidden in wet meadows or marshes, and recently fledged birds spend much of their time hiding in hidden pathways in the vegetation. Both parents feed the young, but males with extensive harems may ration their efforts to benefit just one or two nests. Juveniles can fly and can hunt independently about two months after hatching.

In winter, the larger and more aggressive adult females defend territories with the best habitat, forcing males and juveniles to forage in less productive areas. Unlike most other hawks, sexes differ in appearance, with females brownish and adult males gray, black, and white. Both male and female harriers are brownish during their first year of life.

STATUS AND DISTRIBUTION Found around the edges of the Sierra, harriers favor open areas of wetland, pastures, and grassland but can be seen foraging over sagebrush flats as well. After young birds fledge, until the arrival of snows they readily wander into the mountains and can be found over open slopes, rarely up to the Alpine zone. Local populations often increase in winter with the influx of birds from the north and east.

West Side. Fairly common to uncommon, primarily associated with Central Valley wetlands, pasture, forage crops, and rice (in winter), but their breeding range extends from the lowest reaches of the Foothill zone up into open oak savanna in the north; in the south known nesters only in the Kern River Valley, at about 2,600 feet; during spring and fall migration they are frequently observed soaring in-transit over all habitats up to the Subalpine zone.

East Side. Fairly common to uncommon, pairs breed locally throughout the Great Basin and scattered populations range to the base of the Sierra; common in low-elevation wet meadows, but historical overgrazing and development have impacted and fragmented their best habitats; sometimes breed at higher elevations (up to more than 6,000 feet) in wet mountain meadows.

Sharp-shinned Hawk

Accipiter striatus

ORIGIN OF NAMES “Hawk” from Teutonic root hab, to grasp or seize; “sharp-shin” refers to the raised ridge on the front of the bird’s lower leg; accipiter from L. accipere, to take or seize; L. striatus, striped.