Opisthognathidae, more commonly known as jawfish, are a colorful, somewhat odd-looking family of fish found in reefs throughout both the Pacific and Atlantic Oceans. These fish tend to prefer shallow waters, but some species have been found living in much deeper areas. Because of their bright markings, they are a favorite sight of scuba divers and snorkelers. However, there is much more to these fish than their coloration.
There are dozens of different species of jawfish. Location, coloration, size and behavior vary from species to species, although most species share many similar traits. Although many different jawfish have already been discovered, scientists believe that more species are still undiscovered, or have not yet been properly classified.
Jawfish have slim, long bodies. Generally, they grow to between three and four inches long. However, some species are slightly smaller, and some grow larger, up to nine inches. Along their bodies, Opisthognathidae have long dorsal fins, which usually feature several spikes. The heads of the fish are large when compared to the size of their bodies, and the eyes and mouth are also pronounced. These fish can be found in a range of colors, including red, blue, green, white, orange, pink, and yellow, and may have spots, stripes or swirls. The yellow jawfish is one of the more common sightings in the Caribbean Sea.
The jawfish lives in a burrow in the sand, which it digs itself. The fish scoops sand into its wide mouth, then spits it out in another location. The burrows they create are thin, usually only large enough for the fish to slip into, but can be several inches deep. These fish are extremely territorial. They will fiercely defend their burrows and the area around them.
These diminutive fish feed on very small marine creatures and plankton. They sit tucked into their burrows, with only their heads poking out, waiting for food to float by. This way, the fish are completely protected, and if they feel threatened, they can quickly dart back into the safety of their burrow.
They way jawfish breed is truly fascinating. These fish are mouthbrooders, meaning that once the females release the eggs and they are fertilized, the male will hold them in the safety of his mouth until they are ready to hatch. Although it can take these fish a full year to mature completely, they usually begin digging their burrows only a few weeks after hatching.
