Tagging bad for penguins: Study | World | News | Toronto Sun

Scientists often tag penguins with steel bands under their flippers to track their movements and gather information, but a new study suggests the practice is killing the animals.

Biologists studied 100 king penguins for 10 years, half of which were flipper-tagged and half of which were not. The results, published in the journal Nature, show penguins with flipper bands had a 16% lower survival rate and produced 39% fewer chicks than the band-less birds.

That's because the bands caused a “drag effect,” which made them swim slower and arrive at colony sites for breeding much later than other penguins. They also took much longer to complete foraging trips.
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Penguin observation, notes the study, is a key component of climate-change research. Scientists compare changes in penguin population to things like rises in sea temperatures.

But if the tools of scientific observation are affecting the birds' population, that means the data is tainted.

“Our understanding of the effects of climate change on marine ecosystems based on flipper-band data should be reconsidered,” the study says.