Archerfish Hunt By Spitting Mouthfuls of Water at Their Target

Archerfish attack prey in quite an unusual way—by spitting at it.

They’ve got great aim, too. Adults almost always hit their target on the very first shot, dislodging and bringing down insects and small animals above water up to 10 feet away.

These aptly-named fish hover underwater waiting for prey to come into view, their lips just breaking the water’s surface. They then contract their gill covers and artfully force water through their mouths, shooting a stream of water that is faster at the back than at the front. The trailing edge of water quickly catches up with the rest of the stream, forming a high-velocity blob immediately before impact.

The stream instantly stuns and dislodges the prey into the water, where the archerfish wait eagerly to scoop it up. Even more impressive, they can modify their jets based on the target distance by adjusting the dynamics of their mouth opening and closing.

If the prey is within reach, archerfish will sometimes nix the spitting technique altogether and instead leap out of the water to grab it. But while these fish excel at catching airborne and land-based prey, their spitting technique works underwater, too.

In a study published in the Journal of Experimental Biology, researchers found that archerfish produce jets below the water’s surface to scatter bits of debris or sediment in order to uncover buried food. The jets don’t travel quite as far beneath the water, but the mechanism for aerial and underwater shooting appears to be the same.

Unless you visit an aquarium, you won’t find these guys in the United States, though. The majority of species live in freshwater sources in India, Northern Australia, and Southeast Asia.