Science File / An exploration of issues and trends affecting science, medicine and the environment : Is Stress From Tourists Causing Penguins to Die?

Tourists in Antarctica are stressing penguins to death, contend two researchers at the Institute of Oceanography in Kiel, Germany.

When Boris Culik and Rory Wilson attached sensors to several penguins a few years ago, they found that the birds’ hearts pounded more quickly as humans passed by. That may have caused the 10%-20% fall in the population of two penguin species, they said.

This year, a trio of British researchers--Amanda Nimon and Robert Schroter of Cambridge University and Bernard Stonehouse of the Centre for Biological and Medical Technology and Medicine--disputed those assertions. They said Culik and Wilson, by catching the penguins and attaching sensors to them, had traumatized the penguins. Naturally, the birds responded anxiously the next time they spotted humans, the British researchers said. Furthermore, the Nimon group’s measurements of penguin heart rates--taken by sensors in fake eggs they snuck into the nests--showed little rise when one person approached slowly.

Culik and Wilson replied in the current issue of Nature that tourists generally visit in groups, not one by one. Moreover, analyzing the data of the British researchers, Culik and Wilson found that while the penguin’s average heart rate remained almost unchanged, it jumped initially by nearly 20% before settling back down.

Other researchers have suggested that overfishing of the penguins’ food supply is responsible for the penguins’ decline.