Discards in the Mauritanian shrimp fisheries : an evaluation of lost value

The discards of the shrimp fishery in Mauritania are calculated on basis of direct observations on board of commercial vessels from 2004-2006. Data were collected from 175 hauls in 12 trips. The fisheries for the three different shrimp fisheries take place at different depths and so have a different by-catch and discard composition. The percentage of discards varies from 80.7 to 86.4% in weight which corresponds to a volume of 31 516 tons of fish discarded annually. Commercial species constitute 58.8% of the discards in the gamba fishery and 73.8% in the langostino fishery. In particular the hake and round fish stocks experience a fishery mortality as discards, which is high compared to the mortality induced by the specialized fleet