Application for Scientific Permit – Available for Public Comment
Public comment on the following application for a Scientific Research (Fauna) Permit is open until 27 March.
Applicant: School of Biological Sciences, University of Tasmania
Species/Taxon: Spotted snow skink (Niveoscincus ocellatus)
Location: East Coast and Central Plateau
Title of research: The mechanisms behind evolutionary transitions between genetic sex-determination (GSD) and temperature-dependent sex-determination (TSD).
Aim of project: The aim of this project is to identify mechanisms responsible for evolutionary transitions in sex determination.
Justification: The Tasmanian endemic spotted skink Niveoscincus ocellatus exhibits population divergence in sex determination. This viviparous (live-bearing) skink is common in Tasmania, and has a wide distribution with populations at two climatic extremes: warm-adapted lowland populations, which demonstrate temperature dependent sex determination (TSD) and cold-adapted highland populations, which demonstrate genetic sex determination (GSD). The traditional view that GSD and TSD cannot coexist in the same species has been challenged recently, with mixed sex determining systems observed in reptiles. A recent molecular investigation into the genetic mechanism behind sex determination in N. ocellatus identified a suite of sex-linked genetic markers in both the highland and lowland populations, demonstrating for the first time in Australia the existence of a mixed sex determining system in a viviparous reptile. Having two populations of N. ocellatus with divergent sex determination positions us to make unique contributions to current knowledge of mixed sex determining systems and their role in the evolutionary transitions in sex determination in all vertebrates. In addition, understanding the mechanisms of sex determination in N. ocellatus may aid in determining how populations will respond to climate change and benefit future conservation efforts of other more vulnerable reptile species.
Maximum likely numbers of individuals involved: This project will involve 160 animals (40 males and 40 females from each site) and their offspring.
Activities undertaken and methods: Adult spotted snow skinks will be caught by mealworm fishing (a mealworm attached to a piece of string which the lizard grabs and can then be lifted into a bucket). They will then be transported to the University of Tasmania where they will be housed and sorted into reciprocal mating pairs (lowland female / highland male; highland female / lowland male).
Fate of animals: All adults will be returned to their site of capture after breeding. Offspring from reciprocal crosses will be bred out to maturity at the University of Tasmania and will not be released.
Likely impact on species involved (including any by-catch): Spotted snow skinks are a common reptile species and removal of 80 individuals from each population will not cause a major impact. There will be no by-catch as we can specifically target the species with our capture method.