How to pick out a penguin

It has long been a source of wonder to nature watchers. As huge throngs of seemingly identical penguins crowd the South Atlantic shoreline, birds returning from long fishing trips can unerringly pick out their relatives in the midst of what sounds like bedlam.

Now scientists have discovered that, against all odds, penguins can recognise their significant other by their individual call.

During the research, reported in the journal Animal Behavior, calls made by individual penguins were recorded and then played back to them to see who recognised what. The birds succeeded in identifying their mates, a particularly important ability because penguins share parenting and must be able to find one another quickly when they have been away at sea searching for food.

The research also shows that chicks can home in on the calls of their parents, and ignore the noises being made by other birds. Chicks often wander off when the parents are away and need to recognise calls when they get back to the nest. If they approach adults that are not their parents, they may be subject to a physical attack.