black sea red data book - Department of Biology

Distribution, Habitat type, Critical habitats, Limiting factors. A pelagic species;
immature specimens found in warm waters only, adults also enter cold waters in
search of food. Present throughout the Mediterranean and Black Sea; common
mainly along the North African coasts, from Gibraltar to Libya, off the coasts of
Spain and France, around Sicily and Sardinia, in the Bosphorus and the Black Sea.
Also widely distributed in the Atlantic Ocean, extending as far north as
Newfoundland, the northern coasts of Norway, Lofoten Islands and Iceland.
Threatened by pollution of the Sea of Marmara and by lack of food.
Biology. A fast swimming species, known to perform transoceanic migrations. The
young form schools, sometimes together with other scombroids of similar size.
Enters the Black Sea in spring, staying here till October-November; at the end of
summer it spawns pelagic eggs; a voracious predator, eating all sorts of fish,
crustaceans and cephalopods.
Population trends. A large reduction in stocks, up to a disappearance. On the
Romanian littoral, the species has not been found for the last three decades. No
catches on the Turkish coasts for in the last five years.
Threats. Pollution.
Conservation measures taken. None.
Conservation measures proposed. Fight pollution.
References
Akyuz, E. & I. Artuz, 1957. Some observations on the biology of tuna (Thunnus
thynnus) caught in Turkish waters. GFCM Proc. Tech. Pap. 4 (14): 93-97.
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