Stautus of the Australian sea lion, Neophoca cinerea, in the Great Australian Bight

Abstract

In August 1994, a systematic survey of potential haulout sites of the Australian sea lion, Neophoca cinerea, was conducted along the coastline of the Great Australian Bight from Twin Rocks to Wilson Bluff, a distance of 206 km. A total of 289 Australian sea lions was recorded at 23 sites widely dispersed at the base of the Bunda Cliffs, hauled out on perched platforms formed by collapsed sections of cliff at various levels above the sea. Of these, 37 sea lions were recorded in a deep cave accessed from the sea. The total included 86 pups aged under 12 months, which were probably born in the region; six of these had almost completed moulting their natal pelage and were estimated to be near four months old. Only 12 New Zealand fur seals, Arctocephalus forsteri, were recorded. The Australian sea lion sites located in 1994 were surveyed again in August-September 1995, during a predicted breeding season. In this survey, a total of 284 sea lions was recorded at nine sites in South Australia and one site in Western Australia. This included 90 pups under six months of age, of which 44 were still in lanugo. Overall, we recorded 10 breeding sites and 14 haulout sites. Breeding events were recorded at one colony over three seasons and were consistent with an 18-month cycle. By extrapolating from the number of sea lion pups found in 1994, the population for the Great Australian Bight region in South Australia is estimated to be 613-774. This addition increases the previous estimate for South Australia by 9.3% and the previous total population estimate by 6.6%.