One of South Africa's best-loved birds - the African penguin - is fast disappearing from our coastlines.
This is possibly due to climate change and commercial fishing, according to a presentation yesterday at the International Penguin Congress, in Cape Town.The fate of the African penguin is a barometer of the state of the oceans, and the latest evidence suggests there is cause for serious concern. "They are dying," UK scientist Richard Sherley told the congress yesterday.
"Adult survival has dropped from around 85% to, at its worst, 45%."
The number of breeding pairs on Robben Island had dropped to only 1000, from more than 8000 a decade ago. A similar decline had been recorded at the Boulders Beach penguin colony, a popular tourist attraction.
South Africa is home to 80% of all African penguins so the situation is particularly grave, Sherley said.
The decline has coincided with a shift in the distribution of sardines, a favourite penguin food, he said. The eastward shift in the sardine population appeared to be linked to factors such as over-fishing and a half-degree change in sea-surface temperature.
"We know that food is a big problem [for the penguins]," Sherley said. "Movement of fish populations is a difficulty for penguins because they don't like to move from their breeding sites. Now they have to travel a lot further."
The decline of African penguin numbers is symptomatic of a bigger threat to the world's sea birds, said Lauren Waller, of Cape Nature.
"The penguin has a much smaller range than flying sea birds and so gives early warning of what is happening in the wider ecological context."
Scientists have suggested establishing new colonies closer to the sardines.
"We need to do something but are running out of time," Sherley said.
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