Diet of ballan wrasse, labrus bergylta, and some comparisons with the diet of corkwing wrasse, crenilabrus melops

The gut contents of 99 ballan wrasse (Labrus bergylta: Teleostei; Labridae) sampled between April and July in Galway Bay, Ireland and 95 ballan wrasse sampled between April and June in Dinard, Brittany, France were examined. Decapods and bivalves were the major prey categories in both areas, algae and gastropods were also frequently eaten but in much smaller amounts. The volume of the major food categories did not vary significantly with fish length. However, fish longer than 20 cm did consume greater volumes of bivalves than smaller fish. An increase in dietary diversity during the breeding season was observed. Ballan and corkwing (Crenilabrus melops) exploited many of the same food categories but with different emphases. Bivalves, which were major prey of corkwing, were also very important to the ballan captured simultaneously at the same site.