Last Molt?
In June 2004, Pierre molted what seemed would be his last coat of feathers.
Pierre, who is the alpha male in his colony, began to become antisocial, and was shunned by the other penguins. He wouldn't swim much, since the water was too cold and he could develop potentially fatal hypothermia.
The bald spots spanned his chest, a patch on his back, and his entire tail and head. Medical tests in 2007 revealed that there was no blood infection, the feather biopsies yielded all normal limits, and the only internal dysfunction seemed to be a low-grade kidney problem.
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