Atlantic Halibut - Hippoglossus hippoglossus
Status: Endagered … The Atlantic halibut swims with its eyeless side facing the sea bed
Type: Fish
Location: Northeast and northwest Atlantic including UK and Northern Europe, U.S and Canada.
Size: Can grow up to 2.75 metres with the current record at 233kg
Habitat: On sand, gravel or clay bottoms at depths of between 50 and 2,000 metres.
Main Threats:
The Atlantic halibut is a well-known and much-loved food fish, but it’s not so well known that it is an endangered species. The Atlantic halibut population has declined throughout its range over the last 200 years. Atlantic halibut are particularly vulnerable to over-fishing because they grow slowly and mature late and some populations have almost been wiped out in many areas. If the fish are consistently harvested before they reach maturity, and before they can reproduce, stocks will be at risk of collapse.
Nowadays, most population numbers are too low to sustain target fisheries, and Atlantic halibut are largely taken as bycatch by bottom trawlers and longliners. Surveys indicate that these fish have continued to decline in the North Atlantic over the past two decades, despite being taken only incidentally as bycatch, with little targeted halibut fishing.
Like other species of flatfish, halibut are flattened sideways and lie on one side of their body. As a result, both eyes migrate to one side of the head during development. The Atlantic halibut lies on its left side and has both eyes positioned on its right, facing upwards.
The Atlantic halibut has a relatively slow growth rate and only reaches maturity at 7 to 8 years old (males) and 10 to 11 years for females. Their spawning is seasonal, with the breeding season varying from place to place. After spawning, Atlantic halibut migrate northwards in search of food. Young Atlantic halibut individuals feed on crustaceans such as crabs and prawns, whilst more mature fish feed more on other fish, such as cod, haddock, herring and skate.
The male Atlantic halibut only reaches maturity at 7 or 8 years, the female at 10 to 11 years.
Did you know?
- The Atlantic halibut is the largest species of flatfish on the planet - with the record fish weighing more than a baby African elephant!
- Atlantic halibut have been caught with the remains of seabirds in their guts, as well as indigestible items such as pieces of wood and iron.
- Atlantic halibut are also farmed, and in Scotland are bred and grown in land-based tanks until they reach harvest size at 4 years! Some Scottish farms use organic feed that doesn’t put pressure on wild fish stocks and MCS promotes them on our Fish to Eat list.
What MCS is doing:
- Advising chefs and restaurants, consumers and retailers about choosing sustainable sources of seafood, such as organic farmed Atlantic halibut;
- Campaigning and lobbying at a European level to ensure Common Fisheries Policy reforms are properly implemented to safeguard vulnerable species such as Atlantic halibut;
- Working towards designation and proper management of marine protected areas that could protect Atlantic halibut habitat.