Movements and mortality rates of the Black Duck and Grey teal in South-eastern Australia

Abstract

The movement pattern, mortality, and survival of the black duck are analysed and compared with those of the grey teal. The black duck is more sedentary than the grey teal, although at times extensive movements are undertaken. A regular north-south movement exists in addition to more irregular random dispersal. The mortality rates are shown to be greater and the expectation of further life less for the grey teal than the black duck, the more sedentary species.