Language English Photo: Biodôme Photo: Biodôme OngletsDescriptionDistinguishing featuresAtlantic halibut is a laterally compressed flatfish. Its body is dark or greenish brown on top and cream-coloured underneath. Both eyes are set on the right side of its head, or the top side of its body. Its long dorsal and anal fins fan out around its body. ReproductionSpawning occurs in late winter or early spring, in very deep water, at depths of up to 1,000 metres. The eggs gradually rise closer to the surface as they develop. A large female weighing 90 kg may produce 2 million eggs. DietThe larvae develop underwater, feeding on plankton. Young flatfish measuring less than 30 cm eat invertebrates, those from 30 to 80 cm eat invertebrates and fish and those 80 cm or longer eat only fish. PredatorsThe young are eaten by other fish. The adults are mainly caught by humans. HabitatThese bottom-dwelling fish frequent saltwater at temperatures above 2.5°C. They retreat to deeper waters in winter and enter shallower waters, at depths of less than 40 m, in summer. The young live at depths of 37 to 55 m and the adults, from 165 to 230 m. Ecology, behaviourThese fish are well adapted to life on the sea bottom. With their flattened bodies, it is easy for them to burrow into the mud or sand, to avoid their predators and take their prey by surprise. Their colouring, which resembles the sea bottom, is excellent camouflage. The adults swim and spend their lives lying on the left hand side of their flattened bodies. The larvae have a different shape from the adults. They swim like most other fish, with their bellies facing downward. French nameFlétan de l'Atlantique Scientific nameHippoglossus hippoglossusPhylumChordataClassOsteichthyes (bony fish)OrderPleuronectiformesFamilyPleuronectidaeSizeLength: 0.5 to 2.5 mWeightUp to 50 kg; record: 300 kgLife spanIn the wild: 30 to 35 years, sometimes longerStatusEndangered (IUCN - 1996).