This is

is Scientific Americans 60 Second Science.

I'm Jason Goldman.

Over millions of years,

penguins have evolved a keen sense of where to find food.

Once they're old enough, they set off from the shores on which they hatched for the first time and swim long distances in search of tasty fish like anchovies and sardines.

But they don't search directly for the fish themselves. For example, when young endangered

African penguins head out to sea, they look for areas with low surface temperatures and high

chlorophyll, because those conditions signal the presence of phytoplyton.

And lots of phytoplankton means lots of zooplankton, which in turn means lots of their favorite fish.

Well that's what it used to mean. Climate change plus overfishing

have made the penguin feeding grounds a mirage. The habitat is indeed

plankton-rich, but now it's fish poor. Researchers call this kind of scenario an ecological trap.

It's a situation where you have a signal that previously pointed

an animal towards good quality habitat.

The habitat's been changed usually by rapid induced human pressure so

usually antogenic change and the signal stays but the underlying quality and environment deteriorates.

University of Exeter zoologist Richard Shirley.

He and his team used satellite imaging to track the dispersal of 54 recently fledged

African penguins from eight sites along southern Africa.

Historically, the birds benefited from tons of fish

along the coasts of Angola, Namibia, and Western South Africa.

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