The pathological loss of plumage or feather-loss disorder has been observed in penguins in South Africa and South America since 2006. Thereby, the insulating feathers, an important protection against the cold weather conditions, are falling out in many parts of the body. The cause of this disease remains unknown to date. It is even unclear whether the disease is viral or bacterial. On the positive side, the disease seems to be not as virulent as feared. Only a small numbers of individual birds have been reported to be affected so far.

For the first time, a pathologically induced featherless Adélie penguin has been observed in the Antarctic.
For the first time, a pathologically induced featherless Adélie penguin has been observed in the Antarctic.

In January 2014, the pathological disease was observed in penguins of Antarctica for the first time in an Adélie colony at Hope Bay, in the northeast corner of the Antarctic Peninsula tip. Next to the Argentinian station Esperanza lies one of the largest rookeries of Adélie penguins with an estimated 120,000 breeding pairs. During a routine census a 15 – 20 day old chick was found with partially loss of plumage and thus exposed skin. The remaining feathers came loose very easily, even by gusts of wind. No parasites or other causes could be detected. Despite a seemingly healthy appearance the chick died two days later.

To date, the disease which leads to a large loss of plumage was found only in South Africa and South America.
To date, the disease which leads to a large loss of plumage was found only in South Africa and South America.

Shortly after, in another rookery only 1 kilometer away, a second case was noticed. However, the affected individual could not be examined further and disappeared. It probably died like in the first case. Further cases were not found. Most likely, the disorder only affects penguins with a suppressed immune system or another unfavorable disposition, eventually on a genetic level.

Due to the loss of plumage, penguins are easily exposed to cold and wet conditions.
Due to the loss of plumage, penguins are easily exposed to cold and wet conditions.

The distribution path of the disease from South America or South Africa to Antarctica remains a mystery. Also, a further spread in Antarctica is unknown. Hypothetically, Argentinian base personal who also had contact with penguins in Argentina, could have played a role in it. Also the spreading of the pathogen by tourists travelling from South America to Antarctica cannot be excluded, but is highly unlikely. Disinfecting boots and cleaning the outer gear for visitors has become a general code of conduct to prevent the introduction of pathogens as well as the accidental introduction of new species.

Source: Antarctic Science