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Where to Look for Insects

Insects and their relatives can be found in virtually any terrestrial and freshwater environment and are generally common in and around the locations where people live. In other words, there are a great many insects and their relatives around to enjoy. However, due to their small size and often secretive habits, many insects can go unnoticed; that is, unless you know how and where to look. Observing and studying insects is like opening a treasure chest of natural history. You will quickly discover a hidden world filled with an amazing variety of form and function, including many unique interactions and bizarre behaviors. What is most exciting, though, is that this fascinating world is just outside your front door!

Of course, insects and their relatives occupy an amazing variety of ecological niches–a niche is the individual role and position an organism occupies in an ecosystem. Even a small space in the landscape or single object, such as a blooming plant or downed tree, can harbor a remarkable variety of species and offer hours of exciting exploration. In fact, many of the best places to look for this array of hidden biodiversity are under commonly encountered objects. The following provides a brief overview of where and how to explore these secret and often overlooked sites.

On Logs

Logs provide a bounty of resources for many insects and other arthropods. In many ways, they are a rich, miniature ecosystem alive with critters of all kinds. Insects may live on, in, or under the slowly decaying wood, but there is typically little outward evidence of this diverse system unless the seemingly lifeless log is examined closely and ultimately turned over. The organisms found on or under logs generally fall into one of four basic categories: decomposers, predators, nesters, and hiders. Decomposers are organisms that feed on decaying dead organic material and in the process convert it to hummus, which in turn improves the soil and ultimately provides beneficial nutrients back into the system for other plants and animals to use. The following are a few decomposers: earthworms, sow and pill bugs, snails, beetle grubs, etc.

The diverse array of decomposers found under and around a decaying log attracts many potential predators that seek to take advantage of the available prey. Some examples include ground beetles, earwigs, and so on.

The next group of organisms found in a decaying log are nesters. Like miniature developers and architects, they tunnel through the log as well as the soil beneath, often creating an apartment-complex-like assemblage of chambers for their developing colony. Both termites and ants are nesters that inhabit dead wood. Their activity helps break down the log over time and provides additional holes, cavities and food for other organisms.

Logs also provide valuable shelter to many organisms. Many insects and arthropods are active at night and seek refuge by day in cool, dark, and often moist places. Such locations help minimize desiccation (drying out), provide protection from temperature extremes, and offer ideal hiding places to avoid detection by larger predators. Beyond such temporary occupation, logs also provide longer term habitat for hibernating organisms that seek to overwinter. Many wasps, bees, bugs, millipedes, and even some moth caterpillars, such as woolly bears, survive the cold winter months by hiding out in such sheltered locations.

How to Hunt for Bugs in Logs

So now that you know some of the organisms found on, in, and under logs, it’s time to start exploring. It may be useful to have a magnifying glass and a wide-mouth plastic jar with a lid before heading outside. Once you find a log, take a few minutes to look it over carefully. Some organisms worth observing might be on or around the log. Then, carefully roll the log over. Be prepared to look quickly, as many organisms will rapidly scurry when disturbed. Use the plastic jar to temporarily capture any critters for closer inspection. Studiously examine the underside of the log and the ground beneath for insects and other arthropods. You may wish to use the magnifying class to study some of the more minute organisms. When you are done looking, always gently return the log to its original position, so you don’t significantly disrupt the valuable habitat. Then move on to the next log and continue the process. You will be amazed at all the critters you’ll find!

In Leaf Litter

As you walk through a forest, take note of all the fallen leaves on the ground. This blanket of old, dead leaves and the associated twigs, discarded blossoms, fruit, and shed bark is actually a habitat all its own and home to a surprising variety of invertebrates. Such leaf litter is critical for creating healthy, moist, and nutrient-rich soil for the entire ecosystem. It also harbors a rich array of fungal and microbial life. Thus, leaf litter, just like a decaying log, serves as great habitat for a wide range of insects and other arthropods. Just like with logs, it provides food and protected, often highly moist sites that support decomposers, predators, nesters, and hiders, creating a rich microcosm of life. Earthworms, pill and sow bugs, some fly larvae, snails, slugs, earwigs, and many others feed on dead or decaying plant material and can be prevalent in and under leaf litter. Predators or scavengers found in leaf litter include wolf spiders, some adult beetles and their larvae, ants, millipedes, cockroaches, centipedes, and earwigs; many are active by night and spend the daylight hours hidden under leaves in protected and moist locations. Many of these same organisms nest or reproduce in this environment. Lastly, leaf litter literally provides layers of protection to temporarily shelter critters, enabling them to mitigate temperature fluctuations, avoid desiccation, and escape hungry predators. It also provides longer-term protected sites in which to successfully overwinter.

How to Look for Insects in Leaf Litter

Similar to a dead log, leaf litter initially appears lifeless until you look more closely. Once again, it may be useful to have a magnifying glass and a wide-mouth plastic jar with a lid, as well as a small garden trowel and a plastic bowl before you start. Find a spot in your yard or nearby woods and get down and simply watch for a bit. You may see or hear a variety of critters crawling over or in the leaf litter. Then, use your hands or the small garden trowel and gently start pulling away the layers of leaves and debris, watching closely at what you uncover. The plastic jar can be used to temporarily capture any small organisms for closer inspection. Continue to uncover the debris until you get to the decomposed organic material and soil beneath. Using the trowel, now slowly dig down taking a few small scoops and placing them in the bowl. This will allow you to inspect that moist material in greater detail to see what life lies inside. When finished, return the organic material and soil to the same location and be sure to release any captured critters. You may wish to repeat the process at night and simply observe the ground to see a wider array of active organisms.

Beneath Tree Bark

Dead trees, stumps, and decaying logs typically are covered with loosening bark. While many insects and other arthropods live in or under dead or decaying wood, some can also be found under bark. In many ways, bark provides the same sheltered environment and resources as leaf litter and the area beneath logs. Similarly, many of the same organisms can be found here. A quick word of caution, however: Be very careful around dead trees or large stumps, as they are often unstable. Limbs or large pieces can fall and cause serious injury.

How to Find Insects Under Tree Bark

Once a safe tree, stump or log has been located, start by observing the exterior for signs of life. Do you see any small holes or other signs of activity? Then, slowly and carefully remove pieces of loose bark to see what lies beneath. Look quickly, as many organisms will quickly scuttle away from the disturbance. A wide-mouth jar is again handy, as it enables you to examine your finds. Once the bark is removed, explore both the uncovered dead wood and the back of the bark as you may find organisms on both. Some common organisms that you may encounter include ants and their brood, centipedes, sow and pill bugs, small beetles, beetle grubs, and earwigs, among many others. If you explore these sites in fall and winter, you may also discover many hibernating insects, including lady beetles and bugs.

Beyond any living critters, you will likely also see a history of activity, this can include everything from small holes and chambers to a network of small tunnels and routes that were created by from bark beetles or other wood-boring insects. The network of designs can be quite extensive and appear almost like a piece of artwork. Use the magnifying glass to examine the surface in greater detail. Dead trees and larger stumps will continue decay to further and eventually end up on the ground; continue to follow and explore these hidden resources through time as they decompose and as new organisms use or colonize them.

Looking for Insects on or Under Other Objects

While logs, large fallen branches, and leaf litter are great resources for exploring the hidden world of biodiversity, many other natural or artificial objects provide shelter and habitat for insects too. These include rocks, old boards, landscape pavers, and even flower pots. As you explore, gently turn over many of the larger objects that you find. These are great places to spot earthworms, earwigs, sow and pill bugs, millipedes, centipedes, snails, and cockroaches. Once you’re finished looking, gently return the object to its original position before moving on.

On the Ground

A great many insects and arthropods are ground-dwelling, and they spend all or some of their time foraging, nesting, or otherwise scurrying along the ground in either natural or artificial areas. The specific species and the overall diversity of organisms depend greatly on the type of environment and the level of disturbance present. For example, the organisms found directly around your home and yard are often much different than those found in nearby woods or meadows. Nonetheless, in pretty much any area, there are a number of interesting ground-dwelling critters to discover. A number of organisms, such as wolf spiders, tiger beetles, and ground beetles, are active hunters and move about in search of available prey. Other predators, such as ant lion larvae, build elaborate pit traps to capture passing organisms. Many others are considered scavengers, feeding on a variety of living and dead animal or plant material. These include various ants, earwigs, centipedes, millipedes, snails, slugs, pill and sow bugs, and others. Many are most active at night and spend their time foraging and looking around for available resources.

Ground-Nesting Insects

A great number or insects and other arthropods also nest in the soil. This includes some 70 percent of the native solitary bees in North America as well as many wasps and beetles. In turn, velvet ants search out and parasitize the nests of other insects, often ants and wasps. Fire ants and pavement ants are ground nesters, creating extensive subterranean colonies and actively foraging for food in the surrounding area. Carpenter ants typically nest in dead wood but commonly also excavate the soil beneath fallen trees or decaying logs. Yellow jackets take advantage of existing animal burrows or other cavities to form extensive underground nests. Mud dauber wasps frequent moist ground to acquire the raw materials to build their adobe-like nests. A number of organisms, such as earthworms and slugs, live much of their lives in the soil itself but can often be found aboveground periodically. Rainy days are a great time to spot earthworms, for example.

Some insects also feed at or near ground level. Male butterflies are one example; they regularly visit wet sand, gravel, mud puddles, or animal dung to gain nutrients. Many butterfly and moth larvae will periodically be seen wandering along the ground. When you see them doing that, they’ve finished feeding and are looking for suitable and protected places to pupate or spin a cocoon—or in search of places to overwinter, in the case of the woolly bear. In some cases, the larvae of various insects, including those of regal moths, imperial moths, and tomato hornworms, actually pupate in the soil.

While it may not be the first place you think of to look for insects and other arthropods, the ground is actually a habitat bustling with life of all kinds. Spend some time looking down and you will be amazed at what you find.

On Plants

Plants provide vertical structures in the environment, and they range from ground-hugging shrubs to trees that can reach hundreds of feet in the air. This, combined with the sheer diversity of plant species, provides a wealth of resources for insects—everything from food to shelter—and so plants support an almost countless variety of invertebrate organisms. A large percentage of insects and other arthropods are herbivores. They feed on, or in, every conceivable plant part, from stems, sap, and leaves to roots, flower buds, and fruit. We may be most familiar, though, with the critters that feed on leaves. Their activity is often extremely visible, resulting in noticeable leaf damage. However, it is important to note that the food preference of adult and immature insects often varies tremendously. Butterflies and moths are good examples. As caterpillars, they readily devour leaves and other plant parts; as adults, they feed exclusively on liquid food resources, such as flower nectar, tree sap or the juices from fermenting fruit. A variety of beetles, including tortoise beetles, Japanese beetles, may beetles, and grapevine beetles, also feed on leaves, while some of their larvae or grubs feed underground on plant roots. Grasshoppers, katydids, slugs, snails, and walking sticks are generalist herbivores, nibbling away on the leaves of various trees, shrubs, grasses, or herbaceous plants. Many bugs have piercing-sucking mouthparts that are used to pierce plant tissues and siphon out sap. These include treehoppers, tarnished plant bugs, green stink bugs, large milkweed bugs, leafhoppers, planthoppers, aphids, and cicadas, among many others.

Plant-Based Predators

The tremendous bounty of herbivorous critters attracts an equally rich diversity of predators seeking a hearty meal. These include active hunters, such as paper wasps, cicada killers, robber flies, jumping spiders, mud daubers, lady beetles, and spined soldier bugs, to various scavengers, including carpenter ants and fire ants. Plants also harbor several sit-and-wait ambush predators. The praying mantis is one example; it is one of the most charismatic carnivorous insects on the planet. Similarly, many spiders use plants as support structures for the large webs that help them capture insect prey. Still other insects may nest in or on plants, occupying shelter sites under leaves, in hollow stems, or in existing cavities. A few examples include paper wasps, leafcutting bees, and bald-faced hornets. They are equally useful as secure, protected sites on which to spin a cocoon or form a chrysalis. Plants can also provide the raw materials for nest construction, camouflage, or even body armor. Examples here include leaf cutting bees, which line their nests with pieces of leaves, or bagworms, which cover their bodies with sticks and other plant debris that they spin together with silk, creating a protective disguise.

How to Look for Insects on Plants

Carefully inspecting plants will reveal all sorts of unusual critters. Look for signs of feeding to start, and be sure to inspect all areas of the plant, not just the leaves. You can also put down a white sheet or a cloth beneath over-hanging branches or taller plants and beat the vegetation with a stick. This will knock off many organisms onto the sheet below where they can be more closely observed or temporarily captured. You can also use an insect net to vigorously sweep through grasses and other vegetation and then look inside to see what critters have been dislodged.

Insects on Flowers

Flowers provide an abundance of sugary nectar and protein-rich pollen. These abundant and attractive food rewards attract insects, which help pollinate plants. In many ways, flowers are their own miniature ecosystems; they draw in a wide variety of insects from the surrounding environment, often in large numbers.

Predators Amid the Blooms

The resulting abundance of insects subsequently attracts other organisms with completely different intentions—to prey on the unsuspecting visitors to flowers. These include a wide variety of spiders, robber flies, assassin bugs, ambush bugs, stink bugs, and green lacewings, as well as larger, more charismatic predators, including praying mantises and even dragonflies. As many of these predators sit and wait for passing prey, they can be camouflaged, making them a challenge to spot. Careful and close observation is often needed.

Herbivores on Flowers

A variety of plant-eating insects can be found on or at least near flowers. They feed on the leaves, stems, buds and even flowers of their host plants. Within this mix, you may encounter various caterpillars, beetles, true bugs, aphids, thrips, and grasshoppers. Additionally, you may notice scavenging ants or the larvae of green lacewings and lady beetles, which are attracted to the aphids or scale insects that can be common on many plants.

Looking for Insects on Flowers

Without a doubt, flowers often teem with life and are a great place to start exploring. Before you look up close, stand back and observe for a few minutes. If the flowers are attractive, you should notice a fair amount of activity in the form of insects coming and going. Particularly noticeable insects include bees, wasps, butterflies, and day-flying moths. As you look more closely, you may notice a variety of smaller and less obvious critters, such as beetles and flies. The vast majority of these insects are attracted to the copious quantities of nectar and pollen, and they are generally classified as pollinators.

As you start looking, you will quickly notice that different flowers attract different organisms and that some species, types, and colors of flowers are much more attractive than others. Planting a flower garden in your yard or at your school is a great way to help provide food and habitat for many of these beneficial organisms, and it's an easy way to bring bugs to you, making observation easy.

At Lights

Artificial lights are a magnet for nocturnal insects. They are drawn in from the darkness and often linger until dawn near the light. Scientists aren’t exactly sure why bugs are attracted to artificial lights. It may be that the light interferes with their natural navigational cues. It may also be due to the wavelengths that a particular light emits, as we know insects are more attracted to ultraviolet (UV) and short wavelength colors. Regardless, artificial lights are a sure-fire way to draw in bugs and an excellent place to start exploring.

What You’ll Find

While lights attract a wide array of critters, what you’ll find—and how many will show up—depends on many factors, including the time of year, the ambient temperature, the type of light, and your location. In general, insects are more active on warmer nights. Lights that produce ultraviolet light (often known as black lights) are more attractive and are widely used by entomologists. What you’ll find also changes by season; nearby habitat and competing light sources matter too. As a rule, if your light’s the only one, you’ll attract more insects than if there is competition.

Attracting Insects With a Light

On a good night, a productive light can attract a huge number and variety of organisms. Even from a distance you can spot larger insects circling about or perched on an adjacent structure or wall. Moths are often the most numerous and obvious. They range greatly in size, from giant silkworm moths, such as the Luna Moth or Cecropia Moth, to very tiny micromoths, which deserve a much closer look. A great many beetles are also regularly attracted to light, including the common early season May or June beetles. Katydids, giant water bugs, roaches, green lacewings, dobsonflies, and antlions may be regular visitors too. If you are close to water, mayflies can be tremendously abundant at times, along with stoneflies and caddisflies. Beyond insects, lights often also attract some predators. Spiders often build webs near light sources to take full advantage of the abundant and easily accessible prey.

Observing the organisms that are attracted to artificial lights around your home is a good way to quickly learn about the wide variety of bugs near you. It will give you a quick snapshot of the usual suspects you can expect to regularly encounter. You can also set up black lights to more purposefully attract these nocturnal critters. In either case, regular observation at artificial lights is a fun and easy way to get to know your local insect community.

In or Near Water

Many insects live in or around bodies of water for some portion of their life cycle. Streams, ponds, rivers, and even lakes can provide ideal habitat and access to a wealth of food resources. However, surviving in aquatic environments requires many special adaptations to enable insects to breath, move, avoid predators, and find food. These differences make exploring the insect world around or in water all the more exciting.

Looking for Insects in Water

As you approach a stream or pond, move slowly and carefully watch for movement around the edges of the water and nearby vegetation. Dragonflies and damselflies are common and conspicuous inhabitants of this realm. They fly around the habitat, often scurrying low over the water to lay eggs, hunt for small flying insects, or perch on adjacent or emergent vegetation. Pause briefly near the water and watch the circus of activity. It can be quite amazing! Next, scan the surface of the water for motion. You may encounter clusters of whirligig beetles racing quickly in chaotic circles or water striders darting abruptly forward, as if they were literally walking on the water. Then look below the water surface. Here, you may see backswimmers submerged upside down, wriggling mosquito larvae, or diving beetles moving up and down in the water column. In shallow water or around pond margins you may also see dragonfly or damselfly niads on submerged vegetation or on the silty bottom. A small aquatic or aquarium net can be used to explore this word in greater detail. In many ways, this aquatic environment is truly a hidden world of excitement and discovery.