Temperate Penguins: from the rarest, the Galapagos Penguin, to the most abundant, the Magellanic Penguin

BOERSMA, P. DEE; GARCÍA BORBOROGLU, PABLO; REBSTOCK, GINGER

Victoria

Congreso; 2nd International Marine Conservation Congress; 2010

Society for Conservation Biology

The Galapagos penguin (Spheniscus mendiculus) is endemic to the Galapagos Islands and is the rarest of penguins. The population was thought to be between 6,000 and 15,000 penguins in the early 1970s but its population, like the Humboldt penguin (Spheniscus humboldti) of Peru and northern Chile, collapsed following strong El Niño events in 1972, 1984 and 1998. The Galapagos penguin population is likely now between 1500 and 4700 penguins. The Humboldt penguin is also rare but may number 30,000 birds. In contrast, the Magellanic penguin (Spheniscus magellanicus), which breeds in southern Chile and Argentina, as well as the Falkland/Malvinas Islands, is the most common species of temperate penguin with a population of several million individuals. The main food of Spheniscus penguins are small schooling fish that are already the mainstay of the Peruvian fisheries, and Humboldt penguin populations have already been reduced by overfishing of their prey and mining of guano that destroys their breeding habitat. The size of fish targeted by developing fisheries in Chile, Argentina, and Uruguay as they expand their fisheries are likely to be the food that penguins eat, putting Magellanic penguins at risk from fishing gear and prey depletion. Climate predictions suggest an increase in the frequency and severity of El Niño events, threatening Galapagos and Humboldt penguins. Petroleum pollution remains a threat along the Atlantic Coast particularly in the wintering grounds for Magellanic penguins. The future for these species does not look promising.