Endangered Mediterranean species

Dusky grouper
(Epinephelus marginatus)

Geographic distribution

The dusky grouper is present in the whole of the Mediterranean. It lives near the rocky bottom around poseidonia sea grass. Young fish stay near the coast , the older fish can live at a depth of 200 metres.

Characteristics

Jacques Cousteau said that groupers were the strangest creatures they had encountered in the sea.
The dusky grouper has an oval body and it can reach a maximum size of 1,2 m and a weight of 40 Kg. Its body is covered with small scales, has a short caudal peduncle and a big head with a wide mouth and numerous small teeth.
The dusky grouper has a grey-brown colour with irregular lighter markings (the latin name has Greek roots: the Greek word "epinephelus" means “with clouds on it”).
The colour of the grouper changes depending on its environment.

Behaviour

The young fish live in small groups but become solitary when adult and often hide in deep holes. There are frequent conflicts between individuals to take possession of the holes.
The dusky grouper is a voracious predator and hunts squid, cuttlefish, octopus, crustaceans and fish.
It can live up to 50 years and changes sex with age. It becomes mature at about 5 years of age and it is first female, then it changes sex at about ten years of age.

Influence of man

The grouper is hunted because it is considered a tasty food fish.
Measures has been taken to get a better knowledge of this fish and to study the impact of human activities on its life. In many areas the grouper has been protected from underwater hunting.
Thanks to these protective measures, populations of groupers are increasing.