PARENT SESSION
Oral Session 9: Marine Ecology I: Management.
Presiding: D Policansky
Monday, August 2, 8:00 AM to 11:30 AM, Meeting Room C 120.

Magellanic penguins as sentinels for global change and discovery.

Boersma, Dee^*,1, Rebstock, Ginger¹, Van Buren, Amy¹, ¹ University of Washington, Seattle, WA, USA

ABSTRACT- Magellanic penguins (Spheniscus magellanicus) are in serious decline at their largest colony, Punta Tombo, Argentina, declining over 20% since 1987. The decline of this population highlights the importance of climate change and the need to minimize conflicts with human uses of the marine environment. We have tracked penguins during the breeding season using satellite transmitters (PTTs) since 1997. Magellanic penguins travel long distances to forage during the breeding season. During incubation, penguins often foraged more than 400 km from their nest sites. Penguins foraged closer when they had small chicks and went farther as the chicks grew larger. The time a penguin was away was a good predictor of how far it had traveled during the chick-rearing period. The mean maximum distance satellite-tagged penguins traveled away from the colony during incubation varied among years: in 2001 it was 414 km (S.E.= 36, N= 11), in 2002 it was 592 km (S.E.= 37, N= 10), and in 2003 it was 470 km (S.E.= 39, N= 9). Although surface water temperatures were highly variable among years, penguins foraged in the same general area each year but over the last seven years they appear to be going farther. Climate change is likely to be a serious threat to Magellanic penguin conservation efforts because of potential changes in prey distribution and precipitation patterns during incubation and brooding periods. Detailed knowledge of these penguins suggest that marine zoning will likely be the only useful approach for the conservation of this species at sea because the penguins use large areas of the ocean.

Key words: Spheniscus magellanicus, Magellanic penguin, satellite tracking