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2. Common Blue-Tongued Skinks

Throughout the pages of this book, you’ll see references to individual species. While a particular breed may have a reputation for being placid, easy to handle, ideal for the beginner, or good with children, there is always an exception to the rule. A great deal of your skink’s behavior will depend on how you keep it and how often and how carefully you handle it. That said, getting to know the different species a bit better before you buy a skink will help ensure that you’ll be happy with your choice.

Wild blue-tongued skinks are confined entirely to Australasia, with six types occurring on mainland Australia itself: the Western (Tiliqua occipitalis), the Centralian (T. multifasciata), the Eastern (T. scincoides scincoides), the Northern (T. s. intermedia), the Blotched (T. nigrolutea [the only species to occur in Tasmania]), and the Pygmy (T. adelaidensis). The Indonesian blue-tongued skink, T. gigas gigas, occurs in Papua New Guinea and on a few Indonesian islands with two subspecies: the Kei Island (T. g. keyensis) and the Merauke (T. g. evanescens).

Indonesian Blue-Tongued Skink,Tiliqua gigas gigas

This species is sometimes known as the New Guinea blue tongue, and it is one of the most familiar and commonly kept blue-tongued skinks. It is also known in some parts as the great Moluccan skink, although this name is not often used today. This species can be found in Papua New Guinea, Jobi, the Admiralty Islands, New Britain, and the Bismarck Archipelago.

Under optimal conditions, this skink can grow extremely rapidly. Newborn Indonesian blue tongues measure roughly 6 inches (15 cm) in length from head to tail and can double in length every four weeks or so during their first few months of life. In just eighteen to twenty months, they can reach their full adult size of 19.75 inches (50 cm); those inhabiting the Sarong region can grow even longer.

In most New Guinea blue-tongued skinks, the ground color ranges from a golden yellow to a light brown or sometimes a light, almost silvery gray or gray-brown. Most are dappled with fifteen to twenty slender, dark, irregularly shaped bands across the back and tail. These bands may become indistinct or be absent on the tail, which is frequently completely black with occasionally a little speckling of white or brown. Specimens inhabiting the islands of Ceram and Ambon are virtually solid black all over, with little or no brown.

The venter, or underside, can range from cream to orange and may be peppered with black. The short limbs are usually entirely glossy black and may be spotted with white. The large scales on the broad triangular head are very often edged in black, and a single black stripe usually runs down the center of the back of the neck. Occasionally, a dark stripe extends from the neck to the tail. The tongue is, obviously, a vivid berry-blue color and may protrude and roll forward from the deep pink interior of the mouth during a show of aggression.

Two subspecies are recognized: the Kei Island blue-tongued skink (T. g. keyensis), and the Merauke blue-tongued skink (T. g. evanescens).

The Indonesian blue tongue (Tiliqua gigas gigas).

Kei Island Blue-Tongued Skink, Tiliqua gigas keyensis

The Kei Island blue-tongued skink, as its name suggests, occurs on the Indonesian Kei Islands. Keis start developing their adult colors at around two to three months of age. The ground color, although quite variable, is typically greenish, with spots and bands of black or brown mixed with reds, browns, and tans; some specimens also display yellows and oranges. The tip of this blue tongue’s nose (on a rather stout head) is almost always creamy to white.

The Kei differs from the New Guinea subspecies in several ways: Individual Kei specimens are more impressively built and are therefore more energetic and more active. Kei blue tongues have faded and spotted bands (compared to the New Guinea’s well-defined banding) and very pale orange, or even white, bellies (compared to the New Guinea’s darker, often red, stomach). In addition, Keis always have the same markings on their flanks no matter what color they are, whereas the New Guinea blue tongues lack this pattern. Lastly, the Kei’s head is exceptional and, rather than tapering to a tip, has a nose that comes to an abrupt point.

The Kei Island blue-tongued skink (Tiliqua gigas keyensis).

Merauke Blue-Tongued Skink, Tiliqua gigas evanescens

The Merauke blue-tongued skink, known also as the Faded blue tongue, occurs in southern Papua New Guinea and is the longest of the blue tongues. The Merauke often attains lengths of more than 25 inches (63.5 cm), with some adult specimens reaching 30 inches (76 cm).

Juvenile Merauke individuals can sometimes be very tricky to differentiate from New Guinea blue tongues. Generally speaking, though, the Merauke has several features that help in its identification: It has a huge tail that is usually much longer than that of the typical New Guinea. Although many specimens display a faded grey tinge (hence its alternative name), both the tail and the body are generally fresher, and the striped pattern more distinct. The Merauke’s throat lacks any speckling, and its forelegs usually lack the solid black found in the New Guinea.

Although it might not be as eye-catching as some other blue-tongued species, the Merauke can, even if infrequently, show impressive coloration. Generally, though, the species makes up for lack of visual impact by having a pleasantly placid disposition.

The Merauke blue tongue (Tiliqua gigas evanescens).

Centralian Blue-Tongued Skink, Tiliqua multifasciata

The Centralian, or Central, blue-tongued skink occurs in both desert and tropical habitats, including coastal sand dunes, open shrublands, woodlands, and hummock grasslands in West Australia, Queensland, South Australia, and the Northern Territory. It can attain an average total length of 15.5 to 17.5 inches (40 to 45 cm) and has the characteristic blue-tongue build: a robust body; a large, triangular head; and a relatively short tail. The Centralian’s color is predominately brownish gray with eleven to thirteen narrow orange bands across the length of the body and wider brown bands across the tail.

Active by day, the Centralian hunts for invertebrates and small mammals and forages for plants and berries. At night, it seeks refuge in unused animal burrows or beneath leaves, rock piles, logs, and so on. Females give birth to between two and six young, which is a relatively low rate among blue tongues. The Centralian is listed as “Vulnerable” under the New South Wales Threatened Species Conservation Act 1995, which categorizes threatened species into three groups—Critically Endangered, Endangered, and Vulnerable—by risk of extinction.

The Centralian blue tongue (Tiliqua multifasciata).

Irian Jaya

Irian Jaya is the former name of the province of West Papua in Indonesia that occupies the western half of New Guinea and a dozen offshore islands. At the time of writing, one more species of blue tongue, which has been recognized for over a decade but has yet to be scientifically described, exists there. This skink is currently known as the Irian Jaya or West Papuan blue-tongued skink. With the region’s thousands of tropical and often isolated constituent islands, additional forms of the blue-tongued skink may be discovered before long.

The Irian Jaya (Tiliqua Sp.).

Eastern Blue-Tongued Skink, Tiliqua scincoides scincoides

Sometimes known as the common blue-tongued lizard, the Eastern blue-tongued skink inhabits a wide range of environments, including bushland, montane forest, semi-desert, and cultivated areas, and it even appears occasionally in suburban gardens in Victoria, southeastern South Australia, New South Wales, and southern Queensland. This stout and slow-moving lizard, which is extremely hardy and can live for up to thirty years in captivity, grows to an average length of 19 inches (48 cm), although larger specimens have been recorded. The Eastern’s diet includes invertebrates, small mammals, and plant material.

This blue tongue is extremely variable in color but usually has a grayish to orange-brown ground color with darker bars extending over the back onto the flanks and sometimes continuing onto the pale underside. The scales between these bands are generally marked with dark lateral edges, forming a sequence of thin, dark brown, arrowlike lines that extend the length of the body. A dark brown or black temporal strip runs from the back of the eye to the top of the ear opening on each side. The skink’s forelimbs are basically patternless and are always much lighter in color than the hind limbs. Finally, the Eastern has a fat tail and a comparatively narrow head.

Two subspecies are currently recognized: the Northern blue-tongued skink (T. s. intermedia) and the Tanimbar Island blue-tongued skink (T. s. chimaerea).

The Eastern blue-tongued skink (Tiliqua scincoides scincoides).

Northern Blue-Tongued Skink, Tiliqua scincoides intermedia

Native to Australia, the Northern blue-tongued skink is confined almost entirely to the savannah and tropical woodlands of the Northern Territory and lives an average of twenty years. The Northern skink is very likely the largest and heaviest member of the Tiliqua genus, attaining an average length of 24 inches (61 cm). Despite their large size, Northerns are commonly kept as pets because of their docile temperaments. Females typically give birth to between four and twenty live young.

Comparable in shape to the other members of the genus Tiliqua, the Northern blue tongue has very characteristic patterning: a vivid to soft peachy-orange or even a yellowish color with darker stripes along its back and flanks. The lizard’s underparts are usually a paler, creamier color. Adults and neonates (babies) usually have only negligible differences in their markings and coloration.

The Northern blue tongue (Tiliqua scincoides intermedia).

Northerns are the largest of the blue tongues. Here, a Northern baby is compared to a Tanimbar baby.

Tanimbar Island Blue-Tongued Skink, Tiliqua scincoides chimaerea

Occasionally known as the Sunda blue-tongued skink, this species is limited solely to the Tanimbar (also known as Timor Laut) and Baber Island groups at the lower end of the Makulu Island chain (formerly the Moluccas) in Indonesia. A small species, the adults range in size from 15 to 17 inches (38 to 43 cm). Adult female Tanimbars typically produce litters of up to ten live young, all miniature replicas of their parents.

The extremely smooth scales of the Tanimbar Island blue-tongued skink are shiny and almost glasslike. The body color is typically a golden brown banded with silvery gray. However, this coloration can range from vivid orange to lemon yellow to pure white. With age, many specimens become an overall silvery color. This skink’s belly is a golden yellow that extends onto its throat and chin. The forelimbs are, on the whole, devoid of any pattern and lighter in color than the hind limbs. The head lacks any speckling, and there is no temporal streak between the eye and ear.

The Tanimbar’s scientific subspecies name chimaerea refers to the Chimaera, a fire-breathing she-monster from Greek mythology that was a combination of a lion, a goat, and a snake. The Tanimbar was given this scientific name because of its extreme aggressiveness, which differs greatly from the serene temperament customarily associated with other blue-tongued skinks. If handled frequently when young, captive Tanimbar specimens can become tame to a certain degree; however, this species is not recommended as a pet for children.

The Tanimbar Island blue-tongued skink (Tiliqua scincoides chimaerea).

Blotched Blue-Tongued Skink,Tiliqua nigrolutea

The Blotched blue-tongued skink, also known as the Black and Yellow blue tongue and Southern blue tongue, is a robust and relatively large member of the Tiliqua genus and an inhabitant of New South Wales, South Australia, Victoria, and Tasmania. It resides in both wet and dry environments from coastal heaths to mountain forests. Blotched blue tongues also visit suburban gardens, where the owners welcome them for controlling pests such as snails and slugs.

This species can grow up to 23.5 inches (60 cm) in length. It is omnivorous, feeding on a variety of insects, spiders, arthropods, and plants. An inquisitive lizard, the Blotched blue tongue tames easily and is long-lived. Females produce three to ten live young and frequently interbreed with members of the T. scincoides species.

As far as coloring goes, this is an unusual species among blue tongues because it is dark brown to black with yellowing and many irregular blotches down its back and tail. Two distinct forms of this species—a lowland form and a highland, or alpine, form—seem to exist. The alpine variety is usually larger and inclined to have brighter, more colorful pink or orange blotches on its back whereas the lowland type is darker with darker markings. The tail of this species is particularly fat and comes to a sudden point instead of tapering.

The Blotched blue tongue (Tiliqua nigrolutea).

Western Blue-Tongued Skink Tiliqua occipitalis

The Western blue-tongued skink is found chiefly in Western Australia. In the Northern Territory, it is limited to the far south, and in South Australia, it is separated into western and eastern populations. This species is usually found in dry areas, such as shrublands, grasslands, scrubby woodlands, and dunes. It is omnivorous and active by day, hunting for insects, spiders, and snails, the shells of which it crushes in its strong jaws. The Western blue tongue will also browse for plants (especially fruit-bearing) and carrion. It spends nights in deserted rabbit warrens or beneath rocks, logs, or leaves. The average Western grows to be around 19.5 inches

(50 cm) in length. Females give birth to five to ten brown-and-yellow-banded live young, which are almost immediately independent.

Like most members of its family, the Western blue-tongued skink is typically heavy bodied and short limbed with a broad, triangular head and short tail. A distinctive black marking adorns the rear of each eye. Its ground color is generally dark tan or reddish brown with paler banding across the body and tail; the underside of the body is usually pale.

Like the Central blue tongue, the Western is listed as “Vulnerable” according to the NSW Threatened Species Conservation Act 1995. The main threats to the species are clearance of its habitat for agriculture and the subsequent destruction of the rabbit warrens upon which the skinks depend for refuge, as well as predation by the domestic cat and introduced species such as the European red fox. Because it is one of the rarer species of blue tongue, the Western is seldom kept as a pet.

The Western blue-tongued skink (Tiliqua occipitalis).

Pygmy Blue-Tongued Skink,Tiliqua scincoides adelaidensis

Also known as the Dwarf blue-tongued skink, the Pygmy, as its name suggests, is the smallest of the Tiliqua genus, seldom attaining a length of more than 4 inches (10 cm). It is found only in the grasslands of Adelaide in Australia and lives belowground, usually in the burrows of wolf and trapdoor spiders, where it can be easily overlooked. In fact, in the early 1930s, the Pygmy blue tongue had been so rarely seen that it was thought to have become extinct, only to be rediscovered some sixty years later in 1992.

The Pygmy is pale grayish or gray-brown in color and speckled with darker spots and blotches, with no real stripes or patterns. It has a very slim, short tail; short limbs; and a disproportionately large head compared to its body. Adult males have wider heads but are shorter than females. Females give birth to between one and five young. Unlike the other members of the genus, the Pygmy has a pink tongue.

The Pygmy is extremely rare—scientists believe that only about five thousand exist in the wild today—although efforts are currently underway to increase its numbers. It is illegal to privately own a Pygmy blue-tongued skink and, in fact, only two organizations in Australia are known to have them: the Adelaide Zoo has a small breeding group, and the South Australian Museum has an adult male.

A Blue-Tongue Relative

One other equally fascinating Tiliqua species occurs in Australia: the Stump-tailed skink, T. rugosa. Known also by the names of sleepy lizard, bobtail, and shingleback skink, this slow-moving lizard is closely related to the blue-tongued skinks, with similar habits and a stunning triangular cobalt-blue tongue.

The Stump-tailed skink reaches roughly 12 inches (30 cm) in length; has a short, flattened tail that strongly resembles its head in both shape and size; and has huge, rough, more ossified, and keeled scales (it’s often likened to a pine cone). Recent research suggests that this species is monogamous, and a pair may stay together for twenty years or longer. Gestation lasts for about five months, and adult females give birth to just one to three very big young.

Several varieties of the Stump-tailed skink can be found in Queensland, New South Wales, South Australia, Victoria, and West Australia. They differ in color from an overall jet black to a dark brown with speckled white, yellow, or orange spots (on their flanks in particular).

The Stump-tailed skink (Tiliqua rugosa).