Evaluation of a Tooth-Wear Age Index for Brushtail Possums, Trichosurus-Vulpecula

摘要

Winter (1980) erected a set of criteria for assessing the age of live brushtail possums,nbased on wear on the upper left first molar identified from the dental formula of WoodnJones (1924). Winter tested his tooth-wear classes on a small sample of 25 possums agednfrom about 6 months to 5 years, with only four animals older than 2 years.nSince 1966, Ecology Division has conducted a long-term mark-recapture study of thenpopulation dynamics of possums introduced to New Zealand lowland podocarp forestn(Crawley 1973; Bell 1981). A series of 69 skulls of known-age animals (possums taggedninitially as dependent young) of all ages up to 13 years has been accumulated during thisnstudy, and it is used here to evaluate Winter's age index.