Age Determination in Bennett's Wallaby, Macropus rufogriseus fruticus (Marsupialia), in South Canterbury, New Zealand

Abstract

The ages of 325 Bennett's wallabies were determined from annuli laid down in the periosteal zone of the mandible just in front of the cheek tooth row. The regression of age so determined on molar index was: In (age in months) = 1.8979+0.7727M. There were no significant differences between ages estimated from this regression and those given by Kirkpatrick, who used captive red-necked wallabies of known age. Age could not be estimated from the complex layer structure of tooth cementum. Pouch young were aged from foot and tail lengths by use of data from Kirkpatrick (1965) for captive red-necked wallabies. The problems involved with age determination of pouch young from those data are discussed; the method is considered to be adequate at present.