Unique Fish with a Human Face: Features of Life and Nutrition

Divers who dare to plunge into the cold waters of the northern Pacific Ocean sometimes encounter unusual creatures with long, flexible bodies, whose heads resemble an ugly caricature of human ones. However, these are not victims of an ancient curse, but rare representatives of ray-finned fish.

No, this is not a hybrid of a mermaid and a sea serpent, but a common wolf fish. These fish were known to Icelandic fishermen who dried the heads of the sea monsters they caught and boasted about them to guests. The fishing of wolf fish brought in a decent profit: even the bones and heads were used as feed for livestock, which contributed to an increase in milk fat, while the bile was used to produce quality soap. Despite their external resemblance to moray eels, wolf fish are a distinct species of ray-finned fish. The photograph shows a representative of the genus Anarrhichthys, the first and only one.

Sea Wolves

Wolf fish are often called “wolf eel.” This name is associated with their unique jaw structure: there are several rows of teeth on both jaws, with impressive fangs in the first row. These teeth are necessary for the fish to hunt mollusks and crustaceans — powerful jaw muscles allow them to easily crush both hard shells and fishing gear. However, wolf fish do not shy away from small fish either. Due to this lifestyle, their teeth wear out quickly, so they are renewed in winter: old ones fall out, and new ones grow quite rapidly, becoming long and strong within a month and a half.

Another characteristic feature of wolf fish is their incredibly long dorsal fin. The spine of the eel-like wolf fish consists of about 200 vertebrae, which, combined with the absence of pelvic fins, makes its body flexible and agile. The size and weight of adult wolf fish can vary significantly: on average, the fish reaches 2.5 meters in length and weighs 40-50 kg, however, in 2008, a specimen of eel-like wolf fish measuring a full 8 meters was caught in the Gulf of Finland!

Life on the Bottom

Wolf fish are passive predators that lead a predominantly nocturnal lifestyle. Despite their intimidating appearance, they are very cautious and rarely attack first. Divers often intrude into the territory of wolf fish — thanks to the movements of their dorsal fin and body coloration, the fish camouflages well among the seaweed. Their shelter is a deep burrow or crevice among the rocks, where the predator can peacefully sleep all day. The deeper the wolf fish lives, the more food it has and the faster it grows.

Surprisingly, these creatures are monogamous. In battles for a female, males ram each other with their massive heads and strike with sharp fangs. Natural defenses — thickening around the eyes and thick lips — do not always save them, so the winner often ends up with scars for life. The female lays between 40,000 and 600,000 eggs, which stick together into one large mass and adhere to the bottom. Males guard the eggs while females forage for food.