Researchers from Gonzaga University in Spokane, Wash., monitored the defensive head turns and the level of a hormone penguins secrete in response to stress.
"Head turns of penguins visited for 10 days were significantly lower (in number) than those of penguins visited for 5 days and were not significantly different than for penguins living in the (much frequented) tourist area," lead author, biology Professor Brian Walker, wrote.
The researchers said long-term consequences are much harder to document, especially in long-lived animals such as Magellanic Penguins.
"Our data show quantifying the consequences of human disturbances on wildlife is rarely simple and straightforward," they said.
Magellanic Penguins nest in coastal colonies along the southern Atlantic and Pacific oceans of South America. The penguins in the study live in the largest and most visited colony of Magellanic Penguins at Punta Tombo, Argentina. More than 70,000 people visit annually.
The research appears in the journal Conservation Biology.
Copyright 2006 by United Press International
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