Mortality of brown and south polar skuas by hyphomycetes at Hope Bay, Antarctica

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

Hobart, Tasmania, Australia

Workshop; Workshop on Diseases of Antarctic Wildlife; 1998

During February 1997, 13 Brown skuas Catharacta antarctica and 6 South Polar skuas C. maccormicki were found dead in a small area in the neighbourhood of Boeckella Lake, Hope Bay, Antarctica (63°24´S, 56°59´W). We present the histopathological and microbiological results of these birds. Samples from traquea, lungs, liver, heart, kidney and proventricules were fixed in 10% neutral buffered formalin and 5-m m-paraffin sections were stained with hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS). The necropsy findings revealed that the traquea was occluded with fibrinous material, in lungs several nodule were found and the serosas were enlarged with fibrine. The histopathological study showed traqueitis and pneumonia with a marked intralveolar oedema and congestion in most of the birds. Fungic mycelium were identified in traquea and lungs sections. Moreover, fungic colonies apparently from the same species were isolated from these organs cultured in Sabouraud agar added with yeast extract and cloranphenicol. In addition, no significant results were obtained with the bacteriological and virological studies. These findings suggest that Eumycetes are probably involved in the cause of death of these skuas.