Filming underwater birds and mammals is tricky because having divers nearby can make them act unnaturally.

But the mini cameras allowed scientists to see chinstrap and Adelie penguins from Antarctica sticking together when they hunted for food, called krill.

Scientists hope the pictures can help prevent clashes between fishermen and penguins over the krill.

The pictures appeared in science magazine Biology Letters.

Experts think the penguins work in pairs around half the times they go hunting.