Throughout the last two decades, uncharacteristically warm sea-surfaces have persisted near Triangle Island--off the coast of British Columbia--a haven for these birds. Researchers have been studying the reproductive performance of tufted puffins there since 1975. For years this seabird, but not others, had frequent reproductive failures--seasons when no chicks were reared and researchers did not know why.
The study, published in the current edition of Proceedings of the National Academy of Sciences (PNAS) journal, found that there is a direct relationship between the puffins' breeding success and temperature.
"They raise few chicks when sea surface temperatures are either unusually cold, as they were in the 70s, or especially when they are unusually warm, as they were through most of the 1990s," said author Colleen Cassady St. Clair, a behavioural ecologist from the Faculty of Science. She shared research duties with Carina Gjerdrum--a master's-level graduate from Simon Fraser University and the lead author on the paper--Douglas Bertram, now with Environment Canada and John Ryder and Gwylim Blackburn from Simon Fraser University. Another author Anne Valle, died 21 years ago after a fall she endured while studying the puffins.
The researchers speculate that the biggest reason for these reproductive changes are due to the puffins' prey, which are small fish and mainly a small anchovy-like species called sand lance. "It appears that these fish leave areas with warm water," said St. Clair. "When this warm water surrounds the breeding colonies, the puffins can't catch fish. The adults then appear to abandon their chicks under these conditions, perhaps so that they can forage farther offshore and th
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Contact: Phoebe Dey
phoebe.dey@ualberta.ca
780-492-0437
University of Alberta
14-Jul-2003