Why Are Some Penguin Chicks Losing Their Feathers?

Researchers from the Wildlife Conservation Society (WCS), the University of Washington and other groups are trying to figure out why some penguin chicks on both sides of the South Atlantic are losing their feathers. 

According to Science Daily, feather-loss disorder — which is uncommon in most bird species — first appeared in Cape Town, South Africa in 2006. 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. In 2006, approximately 59 percent of the penguin chicks at the facility lost their feathers; in 2007, 97 percent of the chicks at the facility suffered the same loss, and 20 percent of the chicks in 2008. 

Researchers also found that chicks with feather-loss disorder took longer to grow to a size suitable for release into the wild. The chicks did eventually grow new feathers.

Across the Atlantic in Argentina, scientists from the WCS and the University of Washington also noted feather-loss disorder in the chicks of wild Magellanic penguins, which are closely related to African penguins, for the first time in 2007. The disorder was observed in four different study sites along Argentina’s coastline. Researchers also noted that feathered chicks sought out shade in the hot midday sun, but those without feathers stayed in the sun. Several of the featherless chicks died during the study.

A study on feather-loss disorder appears in the journal of The Waterbird Society about the afflicted penguin chicks in both continents:

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.

“The recent emergence of feather-loss disorder in wild bird populations suggests that the disorder is something new,” said Mariana Varese, Acting Director of WCS’s Latin America and Caribbean Program. “More study of this malady can help identify the root cause, which in turn will help illuminate possible solutions.”

“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.”

A Daily Mail article has a number of images of the featherless penguins. To see Magellanic penguins (parents and chicks) on the coast of Argentina, see this video; another video shows Magellanic penguin chicks in Punta Tombo, Chubut Province, Patagonia, Argentina.


Previous Care2 Coverage

Rockhopper Penguins Threatened By Oil Spill [VIDEO]


Photo of Magellanic penguin chick (without feather loss disorder) by diametrik.

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jane richmond
jane richmond4 years ago


Suzy Harlow
Suzy Harlow4 years ago

quite alarming............it is totally our ever increasing disrespect for our environment

Jane R.
Jane R.4 years ago


Danielle B.
Danielle Raymond4 years ago

I hope they can figure out the problem and put a stop to it right away!

Cheryl B.
Cheryl B.4 years ago


Suzy Harlow
Suzy Harlow4 years ago

the fact that it is most uncommon for feather lost in most bird species is quite alarming......I believe there is probably other species affected by our ever increasing disrespect of our environment.

Colleen S.
Colleen S.4 years ago

scary stuff... :-(

Geraldine H.
Gerri Hennessy4 years ago


Jeannie Miner
Jeannie Fuchs4 years ago

Thanks for the article & I do hope they find the cause of the problem

Judith Corrigan
Judith Corrigan4 years ago

I hope they find out what the problem is.