Trophic ecology of the tench, tinca tinca in two different habitats in North-West of Spain

The habitats preferred by the tench are characteristically sheltered and sh allow with abundant vegetation. Two typical habitats were selected: a river branch and a lake where this cyprinid is abundant. With the aims to unders tand the relationship between tench food and the macroinvertebrate communit y and to detect the possible feeding differences between the two population s studied throughout the year, samplings were carried out seasonally and th e physico-chemical characteristics of the water and the abundance and bioma ss of the macroinvertebrates were analyzed. Tench were caught by electro-fi shing in order to examine gut contents. Chironomid larvae are the preferent ial prey in both habitats. Also preferential are the gastropods in the rive r branch and small crustaceans in the lake. The results obtained suggest th at tench is a rather unselective, generalist predator on the invertebrate c ommunity.