Age Structures of Populations of Kangaroos (Macropodidae) taken by Professional Shooters in New South Wales.

Abstract

Skulls were aged for 4623 grey kangaroos (of both species), 1030 red kangaroos and 84 wallaroos taken by professional shooters in 1973 around eight towns in New South Wales. There was no significant difference in the proportion of adult (4-9 y) to old (10+ y) animals between areas, but there was a difference between red and grey kangaroos. The proportion of young (0-3y) animals, however, varied significantly between areas; this is attributed partly to variation between shooters. A time-specific life table was constructed on the basis of a stationary age distribution; the annual survival was 0.661 for grey kangaroos, 0.729 for wallaroos and 0.790 for red kangaroos. These rates seem influenced by the minimum carcass weights of 12, 13 and 16 kg for the three species respectively, and by the greater tolerance of graziers for red than grey kangaroos. The limitations and potentialities of these observations are discussed and the direction of future investigations indicated.