feather-loss disorder = bisher unerklärter nicht normaler Verlust der Federn bei Pinguinen

Researchers from the Wildlife Conservation Society, the University of Washington, and other groups are grappling with a wildlife mystery: Why are some penguin chicks losing their feathers?

The appearance of „naked“ penguins—afflicted with what is known as feather-loss disorder—in penguin colonies on both sides of the South Atlantic in recent years has scientists puzzled as to what could be causing the condition.


The feather-loss disorder first emerged in Cape Town, South Africa in 2006, when researchers for the South African Foundation for the Conservation of Coastal Birds ( SANCCOB ) first observed the disorder in African (or black-footed) penguins in a rehabilitation center. During that year, approximately 59 percent of the penguin chicks at the facility lost their feathers, followed by 97 percent of the chicks at the facility in 2007, and 20 percent of the chicks in 2008. Chicks with feather-loss disorder, it was discovered, took longer to grow to a size deemed suitable for release into the wild. The chicks eventually began growing new feathers.

One the other side of the South Atlantic, researchers from WCS and the University of Washington observed feather-loss disorder in the chicks of wild Magellanic penguins (closely related to African penguins) for the first time in 2007 in four different study sites along Argentina’s coastline. Researchers also noted that while feathered chicks sought out shade in the hot midday sun, featherless chicks remained in the sun’s glare. Several of the chicks with feather-loss disorder died during the study.

In both instances, penguin chicks with feather-loss disorder grew more slowly than feathered chicks. Featherless chicks were also smaller in size and weight than feathered chicks; both disparities were due to the increased energy spent in thermoregulation in the absence of an insulating coat of feathers and/or down. So far, the possible causes include pathogens, thyroid disorders, nutrient imbalances, or genetics.


„We need to learn how to stop the spread of feather-loss disorder, as penguins already have problems with oil pollution and climate variation,“ said Boersma. „It’s important to keep disease from being added to the list of threats they face.“

Source:
http://www.underwatertimes.com/news.php?article_id=75610380412

http://www.sciencedaily.com/releases/2011/04/110408140924.htm

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