| Summary: | Maintenance and Update Frequency: notPlanned Statement: Nine breeding sites were selected as target colonies for the purpose of ongoing population monitoring. The cost of repeated surveys of every breeding colony in Western Australia was prohibitive, so a sub-sample of colonies representing the geographic and temporal breeding variation was chosen. The locations were Houtman Abrolhos Islands, Beagle Island, North Fisherman Island, Buller Island, Hauloff Rock, Red Islet, Kimberley Island, Glennie Island and Six Mile Island. Sampling was not consistent among all target colonies from 1989 to 2001 due to a number of logistical constraints. The three west coast colonies in the Jurien Bay area (Beagle Is, North Fisherman Is and Buller Is) were visited most frequently and represent the most comprehensively surveyed colonies. Previously published data on pup production and mortality (Gales et al. 1992 & 1994) for the target colonies for the period 1998-1992 were incorporated into this study to look at patterns over an extended timeframe. Breeding colonies were visited towards the end of the predicted breeding season to ensure that the majority of that season's newborn pups would be present. All animals were counted and defined according to one of the following seven classes as originally described by Gales et al. (1992). Bulls - Mature males which have developed a white cap. These animals are of breeding age. Cows - Females of breeding age, grey brown coat with creamy ventral surface. Often recognisable by presence of a pup. Sub-adult males - Males which are distinguishable from mature females by their larger size, broader skull and face and darker ventral coat (spotted or dark grey-brown) Juveniles - Male or female animals which have same colouration as females but are smaller. Newborn pups - Newborn pups which still retain the chocolate-brown natal coat. Moulted pup - Recently moulted pups which are developing the colouration of juveniles, but on the basis of size are less than one and a half years old. After ...
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