The biology of lumpfish
In cooperation with other fishing nations, The Greenland Institute of Natural Resources performs research in the biology of lumpfish these years to secure a substantiated management plan for the species.
The lumpfish (Cyclopterus lumpus), or lumpsucker as it is also called, is found from Canada in west to the Barents Sea in the east. They are present in all parts of the open waters and migrate up and down in the water from great depths to more shallow waters. Researchers at the Greenland Institute of Natural Resources anticipate that the reason for this migration is foraging, but the food source for the lumpfish is not yet fully identified.
The lumpfish is a remarkable creature – almost round with scale-less skin and rows of knobby protuberances, called tubercles, all over. On the underside of its body it has a round sucker disc that can actually hold up to 18 kg. By attaching itself to rocks or seaweed with the disc, the lumpfish, who is in fact a weak swimmer, avoids being carried off by currents.
The females caught in Greenland are up to 45 cm long and can weigh up to 5 kg. The males are significantly smaller with a max of 35 cm in length and a weight of up to 2 kg. In the spring both the females and males swim to shallow waters along the coasts. Here the females spawn around 100.000 eggs equaling up to 1/3 of its weight.
The reason for the relatively low number of eggs compared to other species is that it the level of parental care is relatively high. The male stays with the eggs and is responsible for guarding and venting the eggs until they hatch. The fry lives for the first year hidden in kelp forests or drift with lumps of seaweed. At the age of 3-4 years they are sexually mature and couples will swim to shallow waters to spawn.
A study carried out between Canada, Denmark, Iceland and Greenland is currently mapping the genes and behavior of the existing lumpfish stocks “There are indications that the stocks of lumpfish in Canada, Greenland and Iceland are “different” and goes back to their own hatching waters to spawn, but we do not have more detailed information yet” says Rasmus Hedeholm, Scientist at Greenland Institute of Natural Resources.
A full mapping on the feeding habits, life cycle behavior and whether the stocks have different genes is important knowledge for the future management of the species. The interest for lumpfish roe is increasing in many markets and to ensure a sustainable fishery of lumpfish also in the future, quotas must be set on informed basis. The collaboration between researchers, government, fishermen and the industry is a cornerstone in the future management planning.
