Mortality of Brown and South Polar Skuas by Hyphomycetes at Hope Bay, Antarctica.

LEOTTA G.A., ; PETRUCCELLI M.A., ; MONTALTI D., ; REINOSO E.H.

Kingston, Australia

Workshop; Workshop on Diseases of Antarctic Wildlife; 1998

Australian Antarctic Division

Mortality of nineteen skuas, thirteen Brown skuas Catharacta antarctica lonnbergi and six South Polar skuas Catharacta maccormicki, at Hope Bay (63º 24?S, 56º 59?W) at the northermost end of the is described. Dead birds were kept found and collected within a period of fifteen days in February 1997. They were kept in plastic bags at -20ºC and necropsy was performed. Samples of heart, trachea, lung, intestine, proventricule and liver were taken. Necropsy showed that in nine birds pericardium and peritoneal bags were thicker, with a fibrinous aspect and a whitish colour. In four birds tracheal mucous membrane was removed and light was obstructed with a fibrinous and yellowish substance. In five birds there were nodular wounds of one to two centimeters on the costal surface. Histopathological study was carried out. Samples were stained with H-E and PAS technique. In eleven cases lungs showed pneumonia, intra-alveolar edema, congestion, and the presence of fungus mycelium in the parenchima. An abundant quality of fungous elements was obstructing traqueal light. Micological studies in nineteen samples of trachea and lung were performed. They included microscopic observation, culture and taxonomic identification. The presence of hyphae and taloconides was microscopically demostrated. Eumycetes strains were isolated in all organs with wounds histopathologically described. Taking into previous reports describing a total number of 96 skuas (Brown and South Polar) at Hope Bay, it is possible to infer that mortality of micotic origin was 11%