Cold and temperate sea fish


Identity card


Scientific name:
Cyclopterus lumpus
Year of description:
Linnaeus, 1758
IUCN Status:
Near Threatened

Temperate and cold waters of the North Atlantic Ocean.


It lives on rocky sea beds and in open water (bentho-pelagic fish), generally between 50 and 150 metres deep.


61 cm (female larger than male)


Jellyfish, Ctenophora, molluscs, worms, echinoderms, crustaceans and even small fish such as herring.


14 years


Hen-fish eggs are naturally grey. These "caviar grains" are coloured red and black to give them a more appetising appear

Hen-fish eggs are laid in large quantities, between 100,000 and 400,000 at a time. The eggs aggregate together when they come into contact with sea water.

During this period, the male is very aggressive towards other wolf-eels as well as towards other predators. The Alaska king crab, for example, is particularly fond of them.

Did you know?

Where is the animal to be found?

This fish is found in the cold temperate waters of the North Atlantic where it is commercially harvested primarily by Iceland, Denmark and Norway.

How can it be recognised?

  • Did you know? Females are larger than males (61 cm compared to 50 cm) and during the breeding season, the males turn red or pink. Another distinctive feature is that it has no scales, but a thick skin with bony bulges.
  • It is also known as the fat hen-fish because of its massive, rounded body.
  • Babies are born after 40 days of incubation. They will stay close to the coast for about two years before moving to the open sea. Juveniles feed on copepods. They will be able to reproduce in turn when they are 4 to 7 years old.

What is distinctive about it?

The male guards the eggs during the incubation period by fanning them with his pectoral fin or by blowing water over the cluster of eggs. The female returns to the deep sea once the eggs have been laid.

By using its pelvic fins to form a suction cup, it can hold on to the rocks.

Threat and protective measure

  • Females are caught for their roe, which is the pocket where the what are commonly referred to as "fish eggs" are located.
  • Declining catches reported to the FAO over the past 20-25 years in some fishing areas have prompted the wolf-eel to be classified as Near Threatened by the IUCN.
  • Females are most commonly targeted during the spring spawning season. They are found with adult males in shallow coastal waters for breeding.


Where can I find it at Nausicaá?



Cold and temperate sea fish

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