Age estimation in the Parma wallaby, Macropus parma Waterhouse

Abstract

Pouch young of M. parma were weighed and measured at weekly intervals from birth until shortly after the end of pouch life. Tables giving means and standard deviations of these measurements are provided for estimation of the age of pouch young. The size and shape of the teeth of juvenile and adult animals were studied to facilitate correct identification of the premolar and molar teeth. Vestigial canine teeth were found to be present for a variable period in all juvenile animals studied. Times of eruption of the various teeth were determined for pouch young, juvenile, and young adult animals of known age. Using these data the ages of nine animals from Kawau I., N.Z., were estimated and their subsequent tooth eruption sequences added to the known age sequence. A curve relating age and the molar eruption stage from M 0.2 to M 111.3 is presented for the combined data. The molar teeth appear to be fully erupted at about 5 yr of age, based on extrapolation from the curve. The molar index also shows promise as a means of estimating age. The regression equation : log (age in days) = 2.1912+0.3895 (molar index) is suggested as a working estimate to 3 yr of age.