Abstract

Land Mullets (Egernia major, Scincidae) are large (60 cm total length), powerful glossy black lizards that are restricted to rain forest and associated habitats in southeastern Australia. We conducted the first ecological study of these spectacular animals to evaluate the degree to which anthropogenic activities might threaten population viability. Twelve adult lizards were captured in the Barrington Tops area of eastern New South Wales and implanted with miniature temperature-sensitive radiotransmitters. The lizards were released at their sites of capture and located daily for the next six weeks. In conjunction with surveys of surrounding areas, our data document strong patterns in habitat selection at various spatial scales. The lizards are most abundant in ecotonal forest rather than in either dense rain forest or more open eucalypt-dominated areas. They are most abundant in areas with high numbers of large fallen logs and spend most of their time in or near these logs. Radio-tracked animals were generally located close to clearings (including roads) but actively avoided crossing roads. Land mullets are diurnal heliotherms, basking for long periods each day to achieve body temperatures around 30 C. Their black color increases heating rate, and their large size retards cooling, thus facilitating retention of high temperatures as they forage in cool forest habitats. The animals' ability to take advantage of anthropogenic disturbance (partial clearing of vegetation) suggests that E. major populations are likely to be viable as long as suitable habitat (especially large fallen timber) is available.