A serological study to detect antibodies against microbes in avian mycoplasmosis (Mycoplasma gallisepticum and M. synoviae), and salmonellosis (Salmonella gallinarum and S. pullorum) was carried out. A hundred and twelve Antarctic birds (42 Adelie penguins, Pygoscelis adeliae, 30 southern giant petrels, Macronectes giganteus and 40 skuas, Catharacta antarctica and C. maccormicki) from King George Island, the South Shetland Islands, and Laurie Island, the South Orkney Islands in Antarctica were studied. The serological test used in this study was a rapid agglutination test. According to the results and considering the number of samples analysed, it is reasonable to believe that Adelie penguins, southern giant petrels, and skuas populations of the areas mentioned above are free from mycoplasmosis and salmonellosis.
The cephalopod diet of the gentoo penguin, Pygoscelis papua and the Antarctic fur seal, Arctocephalus gazella was comparatively analyzed at Laurie Island, South Orkney Islands. A total of 125 stomach samples were collected by the water off-loading method from gentoo penguins during the autumns of 1993, 1995 and 1996, and 39 fur seal scats were collected from mid March to April 1988. Cephalopods preyed upon by gentoo penguins were represented by 1974 beaks (1628 lower, 346 upper) which occurred in 50.4% of the samples. Lower beaks identified belonged exclusively to the squid Psychroteuthis glacialis. The mean lower rostral length (LRL) of these beaks was 1.1 mm (range 0.4– 1.8 mm). From the Antarctic fur seal scats 103 beaks (41 lower, 62 upper) were removed from 60.6% of scats which contained prey remains. The cephalopod species identified were Slosarczykovia circumantarctica and P. glacialis which constituted 78.8% and 21.1% in terms of numbers, respectively. The mean lower rostral length for S. circumantarctica was 2.7 mm (range 2.0–3.5 mm), while that of P. glacialis was 1.6 mm (range 1.0–2.5 mm). The foraging behaviour of the two top predators was analyzed and discussed according to the composition and size of their cephalopod prey.