The 1,200+ skink species form the largest lizard family, Scincidae, and among them we find quite a number of unusual animals. Yet the prehensile-tailed skink manages to distinguish itself as unique in not one, but many ways.Largely unknown in the pet trade until the late 1980’s, these arboreal skinks became widely available when logging in the Solomon Islands brought their formerly inaccessible treetop homes crashing to the ground, and left the lizards in reach of collectors. I and others noticed right away that they were quite different than anything we had run across previously.
A Highly Social Lizard
The limited field studies suggest, and our captive observations support, that prehensile-tailed skinks live in hierarchal colonies (a reptilian social group is known as a circulus) and exhibit a variety of highly-developed social behaviors. Group members seem to recognize one another by scent, and mark their territories with waxy secretions. Although often found in pairs, up to 10 individuals have been collected from a single tree hollow, but the functioning of these groups is not understood.
A Placenta and a Giant Offspring
Females, which average 24 inches in length, have a true placenta. They produce 1, rarely 2, huge (to 13 inches) offspring after an amazingly long gestation period of 6 – 8 months. Esteemed veterinarian and herpetologist Dr. Kevin Wright has likened this feat to that of a woman giving birth to a 6 year old child!
Complex Parental Care
The young stay close to their mothers for some time and the females become very aggressive towards people and other skinks after giving birth. Although we do not as yet understand the interactions between adults and young, it is quite clear that those reared in isolation exhibit, if you will, “anti-social” behavior (they are noticeably more aggressive than other skinks, to the point of charging people opening the door of their cages).
Coprophagy (eating of feces) is common, and some believe that this provides the young with important intestinal flora. Breeding occurs year round in the wild and captivity. The young begin feeding at about 10 days of age, and reach sexual maturity in 10 months to 1 year.
Much More to Learn
All told, a strange and fascinating beast. Although captive longevities approach 25 years, we have yet to scratch the surface when it come to understanding prehensile-tailed skink social interactions.
The American Association of Zookeepers has posted an informative article on this species’ fascinating social structure at: