Avian pox in seabirds on Marion Island, southern Indian Ocean

Abstract

Albatrosses are among the most threatened groups of seabirds with the main land-based threats being alien invasive species, human disturbance and habitat degradation. Disease outbreaks in Antarctic and sub-Antarctic seabird populations are uncommon, but in the past few decades there has been an increase in reported cases. The sub-Antarctic Prince Edward Islands (46°S, 37°E) in the south-western Indian Ocean provide breeding grounds for many seabird species, including 44% of all wandering albatrosses (Diomedea exulans L.). In 2015, five wandering albatrosses and two penguins (Eudyptes chrysocome Forster and Aptenodytes patagonicus Miller) with pox-like lesions were observed on Marion Island, the larger of the two Prince Edward Islands. Despite intensive study of the wandering albatross population since the 1980s, the only previous records of such lesions are one case in 2006 and another in 2009 in white-chinned petrels (Procellaria aequinoctialis L.). Molecular and phylogenetic analysis of tissue samples from two albatross chicks confirmed the presence of avian pox virus (Avipoxvirus). This highlights the need for research into the diseases present on sub-Antarctic islands, for strict controls to limit the risk of accidental introduction of diseases through human activities and the need for effective conservation measures in the event of an outbreak.