The Coalfish (Pollachius virens), also known as the Saithe, can easily be confused with other gadids
Coalfish or Saithe
Identification[]
Very similar to the Pollack, with it's three rounded dorsal fins and two anal fins. The lower jaw is approximately equal to the upper jaw, although it may extend marginally further in larger specimens. The chin barbel is minute or even absent in larger fish. The eyes are small in comparison to the overall head dimensions.The pale to white lateral line is (unlike the cod or pollack), STRAIGHT, or only slightly curved. The back is a darkish olive green, to brownish green or blue, that contrasts with the silvery grey / white of the sides and belly.
Breeding[]
Spawns between January to April/May, with February through to March, being the prime time. Spawning occurs off shore in about 100 to 200m of water, and the fry hatch in about 6 to 9 days in water temperatures of between 6 to 9oC. The pelagic larvae drift inshore to shallow water. Rapid growth occurs, so that the young fish may be 25cm in length by the end of their first year.
Habitat[]
Found over a wide range of substrates, from rocky ground and wrecks, through to open waters with sand and gravel. Younger fish tend to be associated with shallow waters (1 to 5m in their first two years), whilst the larger fish tend to be found in small shoals, in deep water over rocks and wrecks.
Food[]
Mid-water feeder, with diet mainly consisting of crustaceans and small fish when young, with a fish dominated diet, consisting of Sandeel, Gobies, Herring, and small Gadids, when older.
Range[]
Shows a more northerly extent in it's range than the Pollack. Found all around the UK, although higher density towards the North and West.
Additional Notes[]
Caught commercially and sold as Coley.
References[]
The Aquarium Project