Incidence of parasitic worms in stomachs of pelagic and demersal fish of the Rockall Trough, northeastern Atlantic Ocean

The incidence of gyrocotyllid worms in chimaeroids and cestode larvae and nematodes in the stomachs of some 13 600 demersal and pelagic fish from the Rockall Trough, northeastern Atlantic is determined. The observations were made in conjunction with a detailed study of the diets of the fish which belonged to 117 species. No dietary sources of the infections could be identified with certainty. Pelagically caught fish, from between the surface and 2500 m depth, had no helminth infestation of their stomachs. Infestations of demersal fish were more pronounced between 1500 and 2900 m than between 500 and 1250 m depth.