Life history of the Coppertail Skink (Ctenotus taeniolatus) in southeastern Australia

The global decline of reptiles is a serious problem, but we still know little about the life histories of most species, making it difficult to predict which species are most vulnerable to environmental change and why they may be vulnerable. Life history can help dictate resilience in the face of decline, and therefore understanding attributes such as sexual size dimorphism, site fidelity, and survival rates are essential. Australia is well-known for its diversity of scincid lizards, but we have little detailed knowledge of the life histories of individual scincid species. To examine the life history of the Coppertail Skink (Ctenotus taeniolatus), which uses scattered surface rocks as shelter, we estimated survival rates, growth rates, and age at maturity during a three-year capture-mark-recapture study. We captured mostly females (>84%), and of individuals captured more than once, we captured 54.3% at least twice beneath the same rock, and of those, 64% were always beneath the same rock (up to five captures). Our growth model estimated that males can reach sexual maturity in as few as 8 mo, whereas females delay maturity until they reach 17 or more months of age. The large body size of females in our population suggests that many individuals were three or more years old. Average monthly survival rate was 86%, which is within the range reported for lizard species in other families. We now have a baseline with which to compare the life histories of other populations of this widespread species, which ranges from temperate to tropical environments. These findings also provide a baseline for examining effects of disturbance or environmental change on life-history traits.