Featured Creature: Mudskipper

What sort of creature lives in the mud, digs holes with its mouth, spits out mudpies, climbs trees and will jump for attention?

The mudskipper, of course (or periophthalmus)!

Tell me about this strange creature, then…

There are 32 living species of mudskippers, an amphibious goby-like fish that can live both in and out of water. They are usually brownish green in color, but can dress themselves up in ostentatious spawning colors to attract a mate, which might strike a familiar ring! 

A mudskipper’s eyes stick up but are retractable as well, while its front pectoral fins are very strong with a bend in them that looks like elbows, allowing them to function like legs in propelling it as it skips from place to place with a funny hopping jump. It uses these fins almost like a person would use crutches, propelling itself along with these fins in a hopping jump that even allows this fish to climb trees or clamber onto low branches. What a great feat for such tiny fins!

Small fins under the mudskipper’s head can also create suction over hard surfaces, allowing some of these species to use this ability to climb roots and rocks to look around for potential prey. This creature can also leap up to two feet, just to express itself or gain notice. This beastie can grow up to 8-12 inches in length, and live from 3 to as long as 20 years.

So where do these strange little fishies live?

They generally live in burrows in intertidal habitats, and dig their burrows with their mouths, spitting out globules of mud outside the opening of their new home. When courting, they jump to display themselves, and when they find a willing female to breed with and lay her eggs in this burrow, the males then take care of these eggs until hatched, bringing to them mouthfuls of oxygen from the surface until that time. The baby mudskippers remain in the burrow for a short while until large enough to survive on the outside.

Mudskippers are also very territorial, and often confront intruders with their open mouths to intimidate rivals, almost as if they’d be yelling at each other if they were vocal enough to do so. When angry, the mudskipper will raise its dorsal fins like ribbed sails as a sign of aggression, so watch out for this sort of flag-waving behavior! During mating season, male mudskippers compete over females. Males develop colorful spots to attract females, and wrestle each other by locking their mouths together and flipping around.

What do they eat? And what eats them?

Some subspecies will eat detritus found on the mudflats where they live, but most will feed on small crabs, insects, snails and even other mudskippers at times! They can hide from larger predators in their burrows, especially at high tide. After the mudskipper eats, it goes into a water-filled burrow to wait for high tide. Surprisingly aggressive, the little fish jumps out to threaten any creature that tries to peek into its home, even animals larger than itself.

What is the mudskipper’s biggest claim to fame?

Did you know that a mudskipper named Muddy Mudskipper was the star of his own show in the TV cartoon series, “Ren & Stimpy”? I wonder if my kids know that!

Well, I guess I’ll just skip along now!

By Fred Jennings