No evidence for Galapagos Plasmodium lineage arriving via Humboldt Current seabirds.

Abstract

Avian malaria, caused by parasites in the genus Plasmodium, has recently been detected in the endangered Galapagos penguin (Spheniscus mendiculus). Understanding possible routes of parasite and pathogen introduction is important for management of small and isolated populations, because island populations can be at higher risk of adverse effects due to lower immunity. One possible means of introduction could be through contact with pelagic birds from coastal South America. In order to better understand the origins of Plasmodium in Galapagos penguins, we used a PCR protocol to test for haemosporidian parasites in Humboldt penguins (Spheniscus humboldti), the sister species of Galapagos penguins, and two other Humboldt Current endemics, the guanay cormorant (Phalacrocorax bougainvillii) and the Peruvian pelican (Pelecanus thagus). None of these seabirds, all sampled at Punta San Juan, Peru, tested positive for haemosporidian parasites. Although the strong Humboldt Current flows from Antarctica up the South American coast and towards Galapagos at the equator, contact rates between these Humboldt endemics and Galapagos birds might still be rare. Despite negative results, this information is important for furthering our knowledge of Plasmodium in Galapagos and in our efforts to effectively manage wildlife diseases.