In Portugal, crustacean bottom trawl fishery mainly targets prawns, shrimps and crayfish and takes place almost strictly in the Algarve, the southern region of Portugal (INE, 2020).
With the exception of the crustaceans all other organisms caught are called by-catch, and many groups of low commercial value or with legislative restrictions (below the minimum size, protected, with quotas) are almost always discarded to the sea, as is the case of deep-sea elasmobranchs (sharks, rays and skates).