Causes of Mortality of Little Penguins Eudyptula minor in Victoria

Abstract

Causes of death of Little Penguins Eudyptula minor found dead at Phillip Island and other coastal areas of Victoria between 1983-1987 were determined by postmortem examination. Adults from breeding colonies were generally in good nutritional condition and had no major parasitism or other disease: deaths were mainly due to trauma from predation or road traffic. Post-fledging birds often had substantial parasite infections that resulted in debilitation and death. Most juvenile mortalities occurred on the coast of western Victoria, sometimes as 'wrecks' of consid- erable numbers of birds that, in the survey period, seemed to be an annual event. The liver fluke Mawsonotrema eudyptulae appeared to be the most pathogenic of the parasites; renal and/or intestinal coccidiosis, intestinal cestodiasis and gastric ulceration associated with ascarid helminthiasis (Contracaecum sp.) were alternative or supplementary problems in some birds. In late winterlspring 1984 and 1985, adult Little Penguins in Port Phillip Bay died of starvation, apparently directly resulting from food deprivation. Affected birds had no major parasitic burdens or other disease that may have influenced their ability to forage. Miscellaneous causes of death included entanglement in discarded fishing tackle and/or plastic debris, the toxic effects of oil in birds contaminated by marine spills and chronic lead poisoning (due to ingestion of part of a lead fishing sinker).