(Phys.org)—Little penguins, also known as fairy penguins, usually have a white belly and dark blue back to camouflage them from predatory eagles above and their fish prey below.
So UNSW and Parks Australia researchers were surprised to come across this very rare piebald chick recently during field research at the little penguin breeding colony on Bowen Island, at Jervis Bay on the NSW South Coast.
"It was sitting on the path leading from the beach, where we had just finished our penguin captures for the night," says UNSW PhD student Sandra Vogel, who is part of a team studying the survival strengths and weaknesses of up to nine colonies along the NSW coast.
"Little penguin chicks leave the safety of their burrows at night to explore their surroundings. We observed this chick, which still had some down feathers remaining around its neck, retreat to its burrow, where we could also spot it during the day. The following night, we encountered the same penguin again in nearly the same spot."
All this season's chick have since left the island and headed for the open sea, and will return in two to three years as adults to start breeding themselves. This little fellow may not be among them.
"It is very likely that the unusual pigmentation will reduce the chances for survival of this penguin," says Sandra. "With its camouflage being compromised, the piebald penguin will have a hard time surviving."
Its unique appearance is due to a genetic defect known as piebald leucism. Piebald leucism differs from albinism in that the affected cells still have the ability to produce pigment but have that specific function turned off. This bird had normal eye colour and feather pigmentation on the lower back, with only spots of blue feathers on its upper back. Blood samples taken from the chick may reveal more about its condition
The research project involves analysing the ability of little penguin colonies to withstand extreme events, like fires and severe disease outbreaks. That means collecting information on survival rates and population sizes, as well as genetic data on the links between populations and migration patterns. At some colonies, birds are also being micro-chipped and blood samples are taken for genetic analysis.
"It is important to forecast population changes in little penguin colonies because the penguins are good indicators of ecosystem health on land and at sea, as well as being an iconic native Australian animal, which might be in need of more protection than it currently receives," says Sandra.
"Unless we know which threats the penguins are most vulnerable to, we might not be able to respond to those threats before the penguins are at risk of serious population declines."
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