How to Identify Mudskippers

Mudskippers are no mere fish: they are completely amphibious animals. Specifically adapted to intertidal zones, these animals can easily shock landlubber primates, who have no idea what sort of animal that they're looking at. By noting the mudskipper's distinct characteristics, however, gobsmacked humans can put a name to a face.

Instructions

1. Mudskippers come in seventeen different species, but all of them exist in tropical or subtropical regions--particularly on the Atlantic coast of Africa, and throughout the Indo-Pacific. As adults, they can be as small as a few inches in length, although certain species can grow up to a foot long.

2. Mudskippers, as per their name, are found in intertidal zones between land and sea, particularly on mud where water levels fluctuate. During high tide, mudskippers are often found close to the water or by their burrows--they often rest on rocks and roots. During low tide, however, they can actively forage on the mudflat.

3. Mudskippers, although they resemble fish, can exit the water for prolonged periods: they use enlarged gill chambers to bring water with them, onto dry land. At the same time, they can absorb oxygen through membranes in their throat and the capillaries in their skin. Their skin, however, must be moist--which is why they often seen rolling in puddles, while keeping their tails in the water.

4. Mudskipper pectoral fins are almost arm-like, even to the point of having pointed little 'elbows.' When moving, these fins leave a distinct pattern along the ground, of symmetrical fin marks spaced about an inch apart, on either side of a long furrow where the body was dragged.

5. Mudskippers do not walk, however: they lunge. When moving, a mudskipper tenses its whole body and then jerks forward, in a motion called 'crutching': certain mudskippers can launch as much as two feet in a single leap. Some species even have adapted pelvic fins that allow them to climb steep angles or objects.

6. Mudskippers have large, goggly eyes that sit on the top of their heads, like periscopes. These stalks often poke out of the water, and can see the surroundings in 360 degrees. They can also, quite remarkably, retract: when they get dry, they are drawn back into the head to wet themselves in a pool of water at the bottom of the eye socket.

Tips & Warnings

• Mudskippers are completely unsuited for captivity in normal fish tanks, because of their distinctive biology.