The eelpouts are the ray-finned fish family Zoarcidae. As the common name suggests, they are somewhat eel-like in appearance. All of the roughly 300 species are marine and mostly bottom-dwelling, some at great depths.
Eelpouts are the only codfish that can live in both fresh and saltwater. They are predominantly found in the Northern Hemisphere. Northeast Atlantic: White Sea, Cheshskaya Guba and Murmansk coast (Barents Sea) southward to English Channel (River Somme); eastern coasts of Scotland, England, also the Irish Sea; the Orkneys, Shetlands and in shallow waters of the North Sea and Baltic. Due to the diverse amount of species, the distribution of eelpouts is all over the Globe.
The body of eelpouts is relatively elongated and laterally compressed. Their heads are relatively small and ovoid. Juveniles have a more rounded snout and relatively larger eye than adults. They have scales beneath the mucous layer on their skin that are minute, cycloid, and cover their entire body.  The dorsal and anal fins are continuous down their bodies up to their caudal fin. They produce a pigment called Vivianite that turns their bones green. This feature has no apparent evolutionary reasoning behind it and is harmless. Eelpouts can come in a variety of colors and sizes based on where in the world they reside. They can commonly be seen as silvery in tone when at sea and brownish golden typically when they inhabit freshwater. Due to their diversity, they can also be found with stripes of color or be completely one-tone down their bodies. Overall, there is no sexual dimorphism in the physical characteristics of eelpouts.
It is currently very hard to research eelpout populations because they are very good at slipping through scientist’s nets in their sampling studies. However, scientists have found, eelpouts are bottom-feeding predatory fish. Their diet consists of small fish, gastropods, chironomids, crustaceans, and fish eggs. They have also adapted to able to breathe air when out of water. Mating occurs from August- September with internal fertilization of the eggs and later females give live birth to anywhere from 30-400 young depending on the exact breed.
Lake of the Woods in Minnesota is known as the eelpout capital of the world for fishermen. Eelpouts are heavily fished using live minnows as bait in the United States. Eelpouts are known for the fight they give anglers fishing which is their main attraction. They are also fishable late into winter which allows for them to be ice-fished along with typical spring and summer angling methods where other fish are not which adds to the excitement for many fishermen.
This family contains about 61 genera and 300 species:
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