Sometimes referred to as the “slime eel”, the hagfish (Myxini class) is not an eel at all. In fact, there is some debate amongst researchers as to whether the hagfish is even a fish! What is known is that the hagfish is one of the most disgusting creatures in the sea. Though it appears to be snake or eel-like, the hagfish has no vertebrae, no jaw and only a partial skull. It has no scales and its body is covered with a soft skin containing many glands that can produce copious amounts of slime, which is used as a defense mechanism.
Most hagfish are around 18 inches in length, have paddle-like tails and no real fins. Rather than a jaw the hagfish has a mouth surrounded by barbels and a pair of horizontally moving structures containing comb-shaped teeth used to pull in food. It has no stomach and possesses three accessory hearts. The hagfish is nearly blind and has primitive eyes that exist just below the skin, allowing it to sense the presence of light but not actually see images.
There are 77 known species of hagfish that live in oceans all over the world. They feed primarily on marine worms near the sea floor, but also have a reputation for eating creatures much larger than themselves. They do this by boring a hole in a dead or dying fish, entering the animal, and literally eating it from the inside out. Hagfish have been known to destroy entire nets full of caught fish in this way.
Hagfish are rarely predated by other marine animals due most likely to their interesting defensive weapon. If a hagfish is threatened or agitated it is capable of excreting large amounts of gelatinous slime into the water. It is believed that this slime is capable of clogging the gills of fish and suffocating them. To rid its body of the slime and keep its own gills from becoming clogged, the hagfish is actually capable of tying itself into an overhand knot. It then works the knot down its body, cleaning the slime off as it goes.
While not a lot is known about hagfish reproduction, some varieties are believed to possess the organs of both sexes and have the ability to change sexes season to season. Depending on the species, hagfish will lay anywhere from 1-30 eggs and have been spotted curled around clutches. When the hagfish are born, they are almost fully developed and appear to be fully capable miniature versions of their parents. Fossils of ancient hagfish seem to suggest that they have evolved very little over the last 300 million years.
- An adult hagfish can secrete enough slime to fill a 5 gallon bucket in a matter of minutes.
- Hagfish have very low metabolisms, and can go several months without eating.
University of California Museum of Paleontology
Sea and Sky