MAGELLANIC PENGUIN (Spheniscus magellanicus) NORTHWARD DISTRIBUTIONAL CHANGES IN PATAGONIA

POZZI, LUCIANA; GARCÍA BORBOROGLU, PABLO; BOERSMA, DEE; PASCUAL, MIGUEL

Boston, Massachusets, Estados Unidos

Congreso; VIII International Penguin Conference; 2010

New England Aquarium

Magellanic penguins (Spheniscus magellanicus) have 63 colonies distributed along 4000 km of coastline in Patagonia, Argentina, with 950,000 breeding pairs. We estimated population size and breeding success at large colonies scattered along Northern and Central Patagonia and assessed trends. To evaluate dispersion we searched five colonies for penguins hatched and banded between 1983 and 2009 at Punta Tombo. Northern colonies increased steadily. Río Negro, increased from 22 breeding pairs in 2002 to 3,751 in 2009. , San Lorenzo (Peninsula Valdes) incremented from 93 breeding pairs in 1977 to around 100,000 in 2008. In Central Patagonia, the biggest colonies declined, including the largest colony in the world, Punta Tombo. Isla Leones decreased from 96,287 pairs in 1995 to 47492 in 2009 Islas Vernacci, an order of magnitude smaller grew from 21,868 pairs in 1993 to 27,736 in 2008 Breeding success was higher in northern colonies. Out of 82,695 birds checked, we found three penguins breeding in the Peninsula Valdes that hatched at Punta Tombo in 1988 and 1991. Dispersal might be an important driver on colonies that are expanding at the northern part of the Magellanic penguin’s breeding range and in the decline of penguins in the central part of their range.