Needlefish can leap from the sea and dive back down to attack small fish prey from above, the first time such behaviour has been seen in fish.

Credit: Australian Natl Fish Coll., CSIRO

Ian Tibbetts at the University of Queensland in Australia and his colleagues observed Tylosurus gavialoides needlefish (pictured) pursuing prey that were in tightly packed shoals in two locations off the Queensland coast. Needlefish normally strike at prey found within about 50 centimetres of their body, but aerial strikes extended their range to more than 2 metres. And such air strikes prevented fish prey from fleeing to the surface and leaping to escape, which they do when they are attacked from below the surface of the water.

The authors suggest that needlefish could be exploiting an optical effect called Snell's window — which limits vision through the water's surface — to mask their approach.

J. Fish Biol. (2015)