The black goby Gobius niger as a potential paratenic host for the parasitic nematode Anguillicola crassus in a thermal effluent of the Baltic

Abstract

Species of fish preyed upon by the European eel Anguilla anguilla were examined for infective larvae of the introduced nematode, Anguillicola crassus, in an area of the Baltic receiving thermal discharges from the Oskarshamn nuclear power station in Sweden. The main paratenic hosts were two benthic species: black goby Gobius niger and ruffe Gymnocephalus cernua, a finding at variance with findings from Central Europe. Larvae and adult parasites recovered from eels fed with larvae from the black goby were scrutinized, and their species identified on a morphological basis. A positive relationship between larval transmission into eels and surrounding water temperature was found. Parasite establishment and developnment in the eel were also favoured at a moderately high water temperature. Thus, in addition to freshwater fish species, those of marine origin may also be important vectors for A.crassus in coastal waters. -from Authors