Ocean perch is most distinctive for its slightly metallic, bright red to gold colouring. Another distinctive feature is its extremely tough scales, which converge into spiny points, and make the ocean perch rough to the touch.
Ocean perch grow unusually slowly and can live up to 50 years. At that age, ocean perch measure up to one metre in length and weigh around 12 kilos.
The sociable ocean perch is found at water temperatures of 3–7° Celsius, close to the seabed at depths of up to 1,000 metres. It feeds mainly on krill and other small shrimps. Herrings make up the bulk of its diet in autumn and winter.