A BBC crew managed to film over 40 of the huge beasts gathering and working together to feast on fish migrating up the Mary River in Australia.

This cooperative feeding behaviour has only recently been discovered - saltwater crocodiles are usually highly territorial creatures.

The animals were filmed with the help of infrared cameras because the spectacle took place during the night.

Mullet migrate in spring; they wait for the high-tide so they can swim up-river to breed.

The crocodiles knew when to gather at the river. The BBC crew filmed them picking the mullet off one by one as the fish swam past.

The footage was recorded for BBC One's Life in Cold Blood.

Life In Cold Blood is on BBC One on Monday, 3 March at 2100 GMT.