The African penguin joins the list of species said to be threatened by climate change - and overfishing. Researchers from the UK and South Africa say penguin numbers in the Benguela upwelling ecosystem have halved in just 30 years. The sardines and anchovies they feed on have moved eastwards, due to changes in water temperature and salinity. Scientists tagged juvenile penguins and found them travelling fruitlessly to their old hunting ground, caught in a so-called ecological trap. SOUNDBITE (English) DR RICHARD SHERLEY, RESEARCH FELLOW AT UNIVERSITY OF EXETER AND BRISTOL ZOOLOGICAL SOCIETY, SAYING: "We did some population modelling which suggests the Western Cape population is about 50 percent the size that it would be if this trap wasn't operating..... The African penguin is endangered. It's declined by more than 50 percent over the last three generations, so over 30 years. The Western Cape population which used to be the stronghold has declined by about 80 percent in the last 11 or 12 years." Juvenile penguins make their first journey to the sea alone. Instinctive cues which used to help them find food now put them in danger. SOUNDBITE (English) DR RICHARD SHERLEY, RESEARCH FELLOW AT UNIVERSITY OF EXETER AND BRISTOL ZOOLOGICAL SOCIETY, SAYING: "They travel over thousands of kilometres to get to these particular locations. They arrive and they find that the fish is no longer there because stocks have either been collapsed, as in the case of Namibia, or the fish have shifted their distribution eastwards. So they're going to the right places but when they get there they're not finding the food that they need and we think they're cueing in on particular cues that tell them that these should be good parts of the environment, but the human impacts have broken the system in a certain way." Researchers have called for some fishing to be suspended and major conservation action in the Benguela. Otherwise the endangered African penguin might die out.
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