Rare visit from rockhoppers not as rare as it should be

AUSTRALIA - The arrival of two northern rockhopper penguins in Denmark on Western Australia's south coast could be a sign of diminishing food supply brought on by changes in ocean temperature.

Northern rockhoppers are normally found on Amsterdam Island in the Indian Ocean, which is 4000 km from Western Australia. These two birds, believed to be one-year-olds, came ashore to moult.

Denmark vet David Edmond has taken in the visitors so they will be safe from dogs and foxes.

Dr Edmond told ABC News he's seen five rockhoppers in the last 12 months - an alarming increase when compared with one or two in the previous 15 years.

"Hopefully it is just a coincidence and it's not that we're having an epidemic of it," he said.

Nick Dunlop from the Conservation Council of Western Australia told ABC News that the most likely explanation for the penguins being so far from home is that they are having trouble finding food, so they had to travel further than usual. When they got up to moulting weight, they were too far away from their breeding colony and had to come ashore on mainland Australia to moult.

Dr Dunlop said the penguins' diminishing food supply is a concern.

"We do know it's got to do with changes in ocean climate at the time which normally affects food supply, their fish move away or their fish abundance declines.

"There's a consequence in change in sea temperature or change in current flows. Normally the climate-induced effects are much greater than the fishery ones but they may actually work in concert in some situations."

As for the two rockhoppers, Dr Edmond is organising to release these likely victims of climate change on a nearby island once they have finished moulting.

Source
Rare penguins washing up on South Coast by Roxanne Taylor, 11 January 2012, ABC News