Archerfish use water to hunt insects!

Archerfish are not a single species, but a family of fish that live in the mangrove swamps of South and Southeast Asia. The name comes from a very unusual hunting method to knock flying insects into the water, which becomes the archerfish’s meal.

Water has some unique visual properties, such as refraction. Refraction occurs when light bends as it enters the water and makes objects appear as though they are located slightly off from where they actually are. A straw in a glass or a branch in a clear stream will appear to be split in two because light moves differently through water and air. Due to refraction, it is difficult to see objects in the air from beneath the water surface. However, archerfish are still able to aim for insects several feet (up to 1 meter) above them. The archerfish can stay at or below the water surface and spit a jet of water at their prey. They do this by closing their gills and squeezing the muscles in their mouth and jaw. Archerfish can hit insects up to 6 feet away with this technique!