Animal Size & Handling Needs, Intermediate Handlers, Lizard, Reptiles

Prehensile-tailed Skink

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Prehensile Tailed Skink 

Corucia zebrata Order: Squamata Family:Scincidae 

Corucia derives from the Latin word coruscus meaning ‘shimmering’. The Latinized form of zebrata refers to the animal’s zebra-like stripes.

Overview 

The Prehensile tailed(PT) skink has many adaptations to discuss with visitors about their arboreal lifestyle. However, some individuals might have aggressive tendencies around their enclosure or breeding season. Presenting them on a perch can minimize those interactions. Limited breeding in captivity can impact availability of ambassadors.

Natural History Information 

Range and Habitat 

Native to the Solomon Islands (located northeast of Australia). Corucia zebrata zebrata is found on the larger islands of the Solomon archipelago southeast of Buka and Bougainville. This includes Choiseul, Guadalcanal, Isabel, Malaita, Nggla, New Georgia, Santa Ana, San Cristobal, Shortlands, and Ugi (Balsai, 1995). The Corucia zebrata alfredschmidti is known from the North Solomons which are comprised of Bougainville and Buka (Kohler, 1997).

It lives in tropical rainforests. Preferred daytime temperature ranges between 75 and 85 degrees Fahrenheit, and 70-75 degrees at night.

Longevity

Prehensile-tailed skinks can live over 20 years and are very hardy if kept under correct conditions.

Ecosystem Role

This species is an arboreal, herbivorous, and crepuscular to nocturnal lizard that inhabits primary humid tropical forests and is not found in secondary growth forests. It prefers the oldest trees, which are the ones with dense foliage and extensive epiphyte cover.

Prehensile-tailed skinks are nocturnal or crepuscular, shy, and secretive. They seldom stray far from their shelter, which is usually a tree hollow. As an arboreal species, it will hang suspended from branches and infrequently come to the ground. During the day, they sleep in hollow limbs or tree cavities preferring the strangler fig tree, Ficus spp. They adapt well to captivity, although it may be difficult to breed them.

Husbandry Information 

Housing Requirements 

Life Cycle Natural History Relevant Information 

  • Nocturnal to Crepuscular 
  • Reproduction (from Zoo Atlanta website): “These lizards are most often found alone or in pairs, but they have been known to form social groups, called a circulus, with other skinks caring for offspring. Breeding takes place in the spring, although they generally only breed every other year or less frequently. Prehensile-tailed skinks are ovoviviparous, producing young by means of eggs that are hatched within the body of the parent. Gestation lasts six to eight months, and babies can measure 1/3 of the adult length, up to 9 inches long, at birth. Unlike many lizards, females of this species only have one baby; twins are possible but rare. The baby stays with its mother for up to six months, which is highly unusual for lizards. Unique among all reptiles, the father may help defend the baby as well. Sexual maturity is reached around 3 years of age.”
  • Breeding takes place in trees and takes up to 15 minutes (Sacramento Zoo)
  • The newborn skink will stay within its “family group” for six to twelve months.  Adult females, as well as other skinks in the group, may be exceptionally aggressive when caring for a newborn. Around a year of age the juvenile will move off to form a new family group.
  • Social Structure (from the PTS Studbook): There have also been observations in captivity of aggregations with groups of skinks in a retreat (hollow tree). This communal torpidity has not been confirmed in the wild. In the wild they can be found singly, in pairs, or somewhat gregarious living in a small family group of 3 to 5 individuals of different sizes and sexes (Coburn, 1996). Groups are territorial of non-members and have a form of primitive scent marking by leaving a waxy coating on surfaces they frequent. Male Corucia are territorial and may be especially so during breeding times.

Habitat 

  • This species is highly arboreal and requires plenty of vertical space and climbing opportunities. The PTS studbook suggests branches with a diameter greater than 10 cm and suspended horizontal platforms. The skink should be allowed to climb from the floor to the top of the enclosure.
  • Cage furnishings should consist of shelters or hiding spots. These can be round cork tubes, hollow logs, or hide boxes. And should be secured at different heights as well as at floor level as some skinks spend time on the ground.
  • There should be enough hides for one per animal and large enough to hold more than one skink. The enclosure should be a minimum of 1m L x 1m W x 1.5m H for an adult trio breeding group.
  • A water bowl large enough for the lizard to soak and defecate in is required.

Temperature, Humidity, Light Cycles 

  • Temperature: Day time temps should range from 82-85°F (26-30°C). Night time drops to mid 70s (20-22°C).  Basking areas should not exceed 95°.
    • PT skinks are a non-basking species, but will thermoregulate by moving into various “microclimates” around their habitat of varying temperatures. It is important to maintain these microclimates and monitor an animal in a new habitat to ensure they are able to maintain proper temperatures. 
  • Humidity: 70-90%. With the high humidity it is important to provide adequate ventilation to prevent mold and fungus from developing. High humidity also helps with shedding issues. Humidity may be achieved with use of a mister system.  Misting will also encourage drinking behaviors/foraging as mist collects onto surfaces in tank. 
    • While encouraging humidity, it is important to ensure air is not stagnant in the habitat. Many use mesh lids to their habitats to allow for air flow if humidity can be maintained.  Small computer fans as well as side vents may also be used to promote ventilation.
  • Light:  Lighting considerations should take into account the species’ need for microclimates throughout their habitat. A 12:12 photoperiod should be offered.  They are active at night; therefore a small amount of visible light which replicates moonlight may be beneficial.
    • Ferguson Zone 2: 0.7 – 1.0 UVI 
    • Basking area (max UVI offered):  1.1 – 3.0 UVI
    • Some use a reverse photoperiod to increase activity during daylight hours. A darkened room is necessary however.

Substrate 

  • A thick, mulch-type substrate will help keep moisture content high.  Coconut chip bark and fiber are commonly used.  Sphagnum moss can also be used in conjunction with bark or in humid hide areas.
  • Cypress bark has also been traditionally used, but is not recommended due to unsustainable harvesting of cypress trees. 
  • Bioactive set-ups (uses invertebrates to promote cleanliness of substrate, often in conjunction with naturalistic substrate/plants) are commonly used with this species. 

Other General Housing Requirements or Management information 

Diet Requirements 

Diet in the Wild 

  • In the wild, this herbivorous, folivorous species eats a variety of plants.
  • From the PTS Studbook: They feed on a wide variety of leaves, flowers and fruits, including their preference for the epiphytic Scindapsus spp. The skink is able to tolerate the somewhat toxic levels of calcium oxalate crystals in the sap of the plant without ill-effect (Sprackland, 1992). Another preferred plant is Piper spp., consuming the vine and leaves from the species. This plant contains alkaloid substances that discourages other animals, yet the skinks ingest without any signs of distress. (Parker, 1983). Epipremnum pinnatum is another common food source, and it too is considered unpalatable and potentially toxic to many vertebrate species. In captivity, these lizards also engage in coprophagy and keratophagy (Balsai, 1995).

Diet under human care 

  • From the PTS Studbook: Diets should consist of primarily dark green leafy vegetables such as: romaine, kale, spinach, escarole, and greens such as: collard, turnip, mustard, and dandelion. Other food items may include apple, banana, cooked carrots, tomatoes, and yellow or orange squashes. These should not by volume be more than 25% of the diet. Skinks that may be difficult to accept new foods can sometimes be weaned gradually using sweet potato baby food spread on the diet. A supplementation of a multivitamin once a week and calcium and trace minerals sprinkled on the greens should be provided. Inclusion of browse items can be given daily, such as Golden Pothos (Epipremnum spp.), grape leaves, mulberry leaves, and forsythia leaves.
  • Kiwi fruit, tomatoes, and grapes have been used as a high value item for training.

Veterinary Concerns 

  •  Prone to retain shed on toes, corners of mouth, tail and around eyes. If not fully removed, drying sheds can restrict blood flow and cause loss of toes and other body parts.  Skinks can be soaked regularly to help remove the shed.  Maintaining proper humidity levels, a large tub for soaking as well as rough areas to promote shed displacement will help to encourage good sheds.
  • As with most reptiles, proper calcium balance is important to achieve through UV access, supplementation and proper diet.  Individuals without a proper balance may present with deformed or slowed growth as well as weakness and lethargy.

Enrichment & Training 

Enrichment 

Behavioral Relevant Information 

  • Skinks are an arboreal species who spend the majority of time in tree canopies and tree hollows. 
  • They are primarily nocturnal to crepuscular and most activity will be within evening hours.
  • They have been documented to readily use vines to transverse between individual trees. 
  • A tropical, rainforest species, they will experience a wide variety of rain types and water sources in the wild. 
  • They will sometimes hang by their tail to forage. 

Environmental Enrichment 

  • Pothos spp. (a common houseplant), is a wild food source of the Prehensile-tailed skink. While toxic to other animals, we offer pothos leaves as food enrichment to our skink (Zoo New England).
  • A wide variety of browse is recommended for enrichment.  Mulberry and grapevine are commonly high value. Flowers like hibiscus and rose petals are also favorites.  Other plants may be offered in habitat, but check with veterinary staff for any ingestion concerns.  Skinks often prefer dense, lush habitat spaces and will spend more time out on perching if cover is provided. 
    • Fake plants are many times used in habitats.  It is important to evaluate if individual skinks will attempt to consume plastic or silk plants.  Ingestion of fake plants is a common hospitalization concern for this species.
  • Perching changes can be a valuable experience for many skinks. Offering a variety of diameters, textures and angles can promote improved physical exercise
    • Individual skinks may take more or less time to investigate new areas of habitat.  Leaving portions of the habitat and hides unchanged will allow for exploration at their own comfort level.
    • Offering cork bark, custom background or even just mesh on sides of habitat can increase usable climbing space for skinks. 
  • Changing lighting and heating arrangement as long as environmental parameters are followed can mimic natural environment.
    • The position of basking areas as well as changing basking surfaces (slate pieces, flat cork bark, humid hide, perch, hammock etc.).  
  • If using misters, having varied time/length of misting sessions.  Can also cover misters with different mesh sizes to promote different mist intensity.  Having misters drip onto surfaces and into different containers can promote water foraging behaviors. 
  • Hides can be offered throughout different areas of habitats. Humid hide boxes (suspended box hide with sphagnum moss substrate, sometimes with basking platform on top) are commonly used in habitats.  
    • Other substrates can be used in hides, but always monitor for potential for consumption of substrate and humidity levels in hide. 
    • Skinks have been known to spend time on mulch in habitat.  Offering hides on floor can promote digging. 

Behavioral Enrichment

  • Food items can be suspended from perching for animals to consume. Using a variety of different bowls, clips and kabobs can offer different foraging patterns.
  • PVC can be cut into a variety of sizes and shapes to hang in habitat for foraging.
  • Novel items of different colors and sizes can be placed in habitat for exploration. 
  • Introducing different textures onto perching and hides.
  • Skinks will scent mark, thus introducing small amounts of novel scent can be enriching.
  • New tubs, pools and even small suspended areas of water.
  • A social species, mirrors can trigger a variety of responses.  Monitor during usage.
  • Hammocks and movable fake vines are commonly used to change paths and resting areas in habitat.
  • Many keepers grow live plants and will rotate out as they are eaten.  Ensure to have plants safe for consumption and soil/pots that are appropriate to be placed in habitat.

Schedule 

  • Zoo Atlanta:  Animals are provided foraging or exercise based enrichment a minimum of four times a week. They can easily be worked into the enclosure.

Other Enrichment Resources 

Training 

Behaviors Trained 

  • Many skinks have successfully been target trained to follow into a transport container or target hold for touch or health checks.
  • Our skink (Baton Rouge Zoo) is trained to climb out of his enclosure onto the handler’s gloved hand. We use a pothos leaf as a reward.
  • Shedd: Our skink is territorial inside of her enclosure but we’ve had success training her to take food via tongs and then guiding her out onto a branch to remove her from the enclosure. Her favorite reinforcers include: cucumber, zucchini, kiwi & the occasional superworm.
  • Reid Park Zoo:  Our skink is very shy and spends majority of his time in hides.  He will target out onto a stick for presentations and receive some small pieces of fruit (blueberries, papaya, apple) as a reinforcer.  Once on stick he will receive dilute mango baby food from a cup.  Pothos has not been high value for training for our individual. 

Reinforcers used & schedule of reinforcement 

  • Pothos (Baton Rouge)
  • Cucumber, zucchini, kiwi, superworms (Shedd Aquarium)
  • Blueberries (quartered), dilute mango baby food (delivered in small lid throughout programming), small pieces of apple, papaya (Reid Park Zoo)

Other 

Social Housing/ Breeding Management 

    • Can be housed socially or individually
      • It is important to offer social rearing and housing situations whenever possible however.
  • A typical configuration is two adult females and one adult male.
      • Juveniles from pairings can be housed within same group for usually between 1-3 years. 
    • Adult males typically are not housed together
    • Females are usually housed together with minimal trouble, but have exhibited spontaneous territorial behavior even after years in the same social environment. It is important to continuously monitor social groupings. 
  • There should be enough hides for one per animal and large enough to hold more than one skink. The enclosure should be a minimum of 1m L x 1m W x 1.5m H for an adult trio breeding group.
  • Introductions can sometimes have some aggressive episodes.  Individuals who have not been parent reared or have not been in social configurations as an adult may be more prone to this. 
    • Offering a wire mesh separation in habitat to allow for a slow introduction may be beneficial for individuals with a history of aggression or low social exposure.

Individual Identification 

  • Dimorphism: Sexing is best done by manual prolapsed of the hemipenes under inhaled anesthetic.
  • Males typically have wider heads than females. 

Programmatic Information 

Messaging Themes 

  • Endemic island species are often under threat from introduced species.
  • Rainforest destruction/habitat loss. One way for people to help the rainforest is to reduce their use of tropical woods. Many rainforest trees are felled each year for lumber, furniture, and other products that end up in countries all over the world. Much of tropical wood imported into the United States comes from South America, particularly the Amazon Rainforest. Flooring, musical instruments, picture frames and other products made of rosewood should be particularly avoided to slow deforestation on Madagascar and to avoid the extinction of endangered or vulnerable rosewood tree species from forests all around the equator. Ask guests to consider used or vintage furniture or new furniture made of wood that has been reclaimed from old structures. There are many alternatives to conventional lumber including flooring and other products made from fast-growing bamboo, and decking made of recycled plastic formed to look like wooden boards. http://environment.nationalgeographic.com/environment/habitats/rainforest-threats/http://www.globaltrees.org/tp_d_nigra.htm
  • The capture of wild animals for the pet trade, and what we can do to prevent/discourage it. Most animals seen at the zoo do not make good pets. Most have specialized dietary, veterinary, housing, and social needs that are difficult or impossible for even dedicated pet owners to meet. Always ensure that your future pet has not been taken from the wild. Capture of wild animals for the pet trade has significantly damaged the survival prospects of species. Captured animals are typically mistreated by profit-motivated traffickers and dealers, resulting in many animal deaths; well-meaning animal lovers may feel like they are rescuing animals by purchasing them but are really perpetuating the cruelty. In addition, many exotic pets are released by their owners when they become too dangerous or demanding, often with devastating effects on local ecosystems. Reptiles have specialized needs, are frequently wild-caught, and damage the local environment if released; guests should be advised to educate themselves and proceed with caution. Domestics are almost always the best option! Many deserving animals are available for adoption at animal shelters. http://www.philadelphiazoo.org/Save-Wildlife/Images/PetWalletBro2012.aspx http://pin.primate.wisc.edu/aboutp/pets/index.html

Threats and Conservation Status 

  • This species is listed as CITES II, but is not currently listed by IUCN. The U.S. Fish & Wildlife Service does not have a listing for the prehensile-tailed skink.
  • Extensive logging is the major threat to its survival: The Solomon Islands are being cut and developed at an alarming rate; some 90% of their tropical rainforest have been lost due to extensive logging. Corucia cannot stand this type of habitat loss as being so dependent upon old-growth forests.
  • Past commercial collecting for the pet trade where large numbers of lizards (that have a low reproductive rate) had been exported from the only islands where they are endemic caused a negative impact on the wild populations. Currently, there are no legal imports for commercial activities, although wild-caught prehensile-tailed skinks are still finding their way into the pet trade.

Interesting Natural History Information 

  • Babies can measure up to 9 inches at birth. Unique to reptiles, the father may help defend the baby.
  • Have been known to form social groups called circulus, with other skinks caring for the young skinks.
  • The male PT skink will change his behavior when he smells the female. This includes head bobbing or vibrations and increased aggression in the form of biting.

Did you know…

  • This is the largest species of skink and the only one with a fully prehensile tail.
  • Also called “monkey-tailed skinks” or Solomon Island skink
  • There are two currently recognized subspecies of the prehensile-tailed skink, the common or banded prehensile-tailed skink (Corucia zebrata zebrata) and the Bougainville prehensile-tailed skink (C. z. alfredschmidti)

Handling & Presentation Tips 

  • This animal is usually presented on a branch or on gloved hands due to their sharp claws and strong grip. It can also demonstrate its abilities.
  • Full/elbow-length gloves are recommended for handling.
  • The skink has a tendency to want to be up high so positioning your hands so that it can continually climb up will keep the handler safe and the lizard occupied
  • Maryland Zoo in Baltimore: Handled on a stick; can become aggressive.
  • Zoo New England, Stone Zoo: Prehensile-tailed skinks do have more sensitive temperature and humidity requirements than some other reptiles, and “new” individuals to handling require some work to train. Additionally, their claws are very sharp.
  • ZooAtlantaPTSkink

(Zoo Atlanta)

Use Guidelines 

  • Zoo Atlanta: They can be used for a 30 minute encounter maximum with a 30 minute rest period between encounters with a limit of three encounters per trip. (This can be adjusted based on your animals interest.)

Public Contact and Interaction Guidelines 

  • Animals are permitted to be touched with two fingers on the back by one person at a time. This can occur on a handler’s gloved hand or on a perch.
  • Hand sanitizer is distributed to everyone who touches the animal. The public is advised to also wash hands with soap and water. The CDC guidelines are stated for visitors touching reptiles that are under 5 years of age due to the potential of all reptiles to be carriers of salmonella.
  • Animals are presented at shows, education programs, informal animal encounters, and special events.

Transportation Tips 

  • Shedd: For encounters we transport ours using a mesh bird carrier (PetPocket brand), with branches inside. Once at the encounter space we take her out and display her on a branch. Though she is territorial inside of her enclosure, she is normally not territorial or aggressive when removing her from her transport
  • PT skinks are transported in 48 quart hard sided coolers, often with a branch across the middle to provide something for them to climb on. 
  • Some facilities will utilize a portable hand warmer or rice sock to keep temperatures elevated in the travel enclosure.

Crating Techniques

  • Brandywine Zoo: Our PTS travels in a Coleman stackable cooler, like the one pictured below.   cropped cooler
  • A layer of newspaper is placed on the bottom to aid in traction and clean up. Astroturf mats or carpet squares can also be used. 
  • A log can be attached through the sides of the cooler to allow for perching during transportTransport pic
  • Cooler is secured with a bungee to prevent them from popping open the lid while in transit.

Temperature Guidelines

  • PT skinks shouldn’t be presented below 60°F or above 90°F. Keep animals in shade/ sun as appropriate using your comfort level as a guide.
  • When traveling below 60F, it is a good idea to provide supplemental heat from rechargeable hand warmers, rice socks, or hot water bottles. The supplemental heat should be comfortably warm, not burning hot. It should also be placed to one side of the carrier and wrapped or covered with a sheet of newspaper or towel.

Acquisition Information 

  • Prehensile-tailed skinks are an SSP Yellow program. Please contact Program Leader Sam Curtis, Sacramento Zoo (swcurtis@saczoo.org)
  • Philadelphia Zoo has bred prehensile-tailed skinks for educational purposes. 
  • Contacting local breeders can also be a way to reduce stress of transport.  Ensure to always properly vet breeders and ensure they are following best practices. 
    • Purchasing wild-caught prehensile tailed skinks is highly discouraged.  The species is increasingly threatened in its natural habitat and it is unsustainable to promote their removal. 
      • Wild-caught individuals have also failed to thrive and exhibited more aggressive behaviors while in human care.

Resources 

Contributors and Citations 

Comments from the Rating System 

  • Maryland Zoo in Baltimore: Handled on a stick; can become aggressive.
  • Zoo New England, Stone Zoo: Prehensile-tailed skinks do have more sensitive temperature and humidity requirements than some other reptiles, and “new” individuals to handling require some work to train. Additionally, their claws are very sharp.