Mortality of Magellanic penguins at Queule, Araucania region, Chile

R. Schlatter et al 2009. Boletín Chileno de Ornitología 15(2): 78-86

In late March 2009 a massive mortality of at least 1,380 Magellanic Penguins (Spheniscus magellanicus, Forster 1781) was recorded at Queule Beach, southern Chile. About 48% of the animals were adults and 52% were juveniles. We collected a sample of 16 individuals (7 adults and 9 juveniles) for bacteriological, virological and histhopathological analysis. Most of the birds were in visible good body condition and had food in their stomachs (Araucarian Herring, Strangomera bentincki) which excludes food shortage as cause of death. We detected several hepatic injuries compatible with avian cholera, but PCR analysis discarded this possibility. At least 7 birds presented abrasions and injuries in their feet most likely derived from entanglement. Through interviews with officers at governmental agencies, researchers and local fishermen, we established that an unusually large fishing effort (using fishing nets) occurred in the offshore area during the time the massive mortalities were recorded. All these aspects allow us to propose that the most probable cause of death for the Magellanic penguin was entanglement in fishing nets and subsequent drowning. This occurred when penguins were migrating northwards, a typical behavior of the species during this time of the year (austral autumn). We propose the establishment of regional groups of specialists to provide a quick response to such mortality events in order to take fresh samples and allow a proper assessment and quantification of the dead animals.