April 13, 2011
UW biologists stumped by ‘naked penguins in Africa and South America
In the last five years, a growing number of penguin chicks on both sides of the Atlantic Ocean have been afflicted with a condition called feather-loss disorder, and UW conservation biologists are trying to figure out why.
The malady first appeared in African, or black-footed, penguins near Cape Town, South Africa, in 2006, and turned up the following year in Magellanic penguins at four different study sites in Argentina, said Dee Boersma, a UW biology professor and conservation biologist.
In Argentina, where Boersma has studied Magellanic penguins since the 1970s, the scientists noted that featherless chicks, unlike their feathered counterparts, remained exposed to the midday sun and several died.
Across the Atlantic, researchers with the South African Foundation for the Conservation of Coastal Birds noted that about 59 percent of penguin chicks at a rehabilitation center near Cape Town lost their feathers in 2006. That jumped to 97 percent the following year before declining to 20 percent in 2008. The scientists noted that chicks with the disorder took longer to grow big enough to be released into the wild, but all the chicks eventually began growing feathers.
“Theres no sign of abatement,” Boersma said. “If this spreads farther south, it could kill a lot of chicks of other species of penguins in colder environments.”
The cause of the feather-loss disorder is unknown, and it is uncertain whether the two cases are related, Boersma said. She noted that, because the disorder was more common in the African rehabilitation center than in the wild, it might be facilitated by close contact or enclosed spaces.
The findings are documented in a paper published in the journal Waterbirds. The lead author is Olivia Kane, a UW doctoral student in biology.
We are not any closer to knowing what is causing this new disorder,” Kane said. “After the penguin chicks grow their next plumage they appear to have normal plumage and no long-term damage. Feather loss can be caused by nutrient imbalances such as iodine deficiencies, but this does not appear to be the case because the chicks in the rehabilitation center in South Africa received the same diet as in previous years. So I cannot guess what might be causing it.”
Besides Boersma, other co-authors are UW biology graduate student Jeffrey Smith, Nola Parsons and Vanessa Strauss of the South African Foundation for the Conservation of Coastal Birds, and Pablo García-Borboroglu and Cecilia Villanueva of Centro Nacional Patagónico in Argentina.
“We need to learn how to stop the spread of feather-loss disorder, as penguins already have problems with oil pollution and climate variation,” Boersma said. “Its important to keep disease from being added to the list of threats they face.”
The research is supported by the Wildlife Conservation Society, Friends of the Penguins, the Province of Chubut (Argentina) Office of Tourism. the International Fund for Animal Welfare, the Norway South Africa Fisheries Agreement, the National Research Foundation of South Africa, the University of Cape Town Research Committee and the Earthwatch Institute.