ESR SPECIAL PrePrint (2008) - Abstract

ABSTRACT: With disease playing an often unknown role in populations of endangered species, necropsy studies are an important component of conservation management programmes. In the present study, we investigate causes of mortality in the free-living population of endangered pink pigeons Columba mayeri, endemic to Mauritius. Fifty carcasses of free-living pink pigeons were found over a 5 yr period between January 2002 and December 2006. Causes of mortality and other post-mortem findings are reported for 43 of these birds, which were aged between 6 wk and 15 yr. The protozoan disease trichomonosis was the most common cause of death, with 22 (52%) freshly dead birds identified as dying from this disease. Four birds were suspected to have been killed by introduced mammalian predators, 4 died as the result of an impact injury and most of the remaining birds either died of unknown causes or the carcasses were too decomposed for necropsy. Our study highlights trichomonad protozoal infections as an important mortality factor in post-fledging pink pigeons in recent years. A number of other novel or rarely described parasites are also identified, highlighting the relative paucity of knowledge on background levels of parasitism in free-living endangered species.

KEY WORDS: Conservation management · Disease · Mauritius · Necropsy · Predation · Trichomonosis