Sparus aurata (Linnaeus, 1758)
Photos by George Reclos. Aegean Sea, Serifos island, August 2004.
Natural Habitat: The animals are found over sea grass beds or sandy bottoms of the coastal waters. They are bottom dwelling species and usually they live solitary or in small and loose groups.
Depth: Usually, they occur at depths between 15 and 30 m, but larger individuals inhabit deeper waters (up to 150 m). The very few times that I have encountered this species it was at a depth no more than 1.5 meters.
Size: The animals may reach a maximum length of 70 cm (SL) and a body weight of more than 16 kg, although normally they do not exceed 35 cm. They show longevity of over ten years in captivity. The largest specimens that I have seen were about 40 cm.
Food: They mainly feed on invertebrate matter and sometimes they shall take plants or phytoplanktonic organisms, although they mainly prefer shellfishes (mussels and oysters).
Distribution: Mediterranean Sea. Great Britain to Senegal. Canary Islands, Cape Verde islands. Doesn’t exist in Madeira but open sea aquaculture of gilt-head bream has started so it is just a matter of time till the first specimens escape.
Common name: Gilt-head bream
Breeding: The animals become mature and ready to reproduce after the 1st year of their life, when they are larger than 25 cm and change sex from ♂♂ to ♀ animals (protandric hermaphrodites). Quite frequently, due to damages of their growing cages, gilthead breams flood the areas where these cages are located, but they are easily shot from underwater spear hunters as they are familiar to humans so they approach them with inglorious results. In the wild they spawn in the winter but in aquacultures they are conditioned and they breed all year round under controlled methods (changes on the specific gravity of the water, temperature and photoperiod). Their larvae develop planktonic. Their larval stage lasts about 50 days at temperature about 17 to 18° C.
General information: It is found in all kinds of water (fresh, brackish, marine), although we all know it as a marine animal, which is true for adults, but fry and juveniles will tolerate brackish water, which is rich in food, as well as fresh water (they enter the estuaries). It is a highly appreciated food fish, which is widely cultivated for its tasty flesh, all over Mediterranean Sea in well organised aquacultures. More or less, the methods used are similar to the ones used for the massive breeding of D. labrax, D. puntazzo and Lutjanus griseus in captivity. Wild populations do exist but they are small in numbers. The volume of tanks to house these animals should be very large and it should be offered a great variety of foods. They are quite vulnerable to ammonia even low levels (even as low as 0,3 mg/l). If someone takes a close look of the lower jaw of the fish he can see a bone-like formation with many small and rounded teeth protruding from it. This is used by the fish to crash the shells of the various shellfish that it eats.
Text by Andreas Iliopoulos & John Reclos