New Zealand Journal of Ecology (1978) 1: 138- 144

Pup mortality of the New Zealand fur seal (Arctocephalus forsteri, Lesson)

Research Article
R. H. Mattlin  
  1. Department of Zoology, University of Canterbury, Christchurch, New Zealand

Mortality of New Zealand fur seal pups from birth until approximately 300 days was investigated on Taumaka, Open Bay Islands, Westland, New Zealand (43° 52' S, 168° 53' E) between December 1974 and August 1976. In both 1974-75 and 1975-76 there was an approximate mean mortality rate of 20 percent from birth to 50 days, and 40 percent from birth to 300 days. Starvation was the greatest cause of mortality, accounting for 70 percent of the deaths to 50 days. Other deaths were a consequence of stillbirths, suffocation, drowning, trampling and predation. First year mortality could have been as high as 50 percent of the total pup crop. Human disturbance killed pups indirectly by causing panic on the rookery. Tagging with monel metal cattle ear tags on the posterior edge of the foreflipper may have increased mortality.