Helminth parasite communities of the conger eel in the estuaries of Arousaand Muros (Galicia, north-west Spain)

The nematodes Cucullanus hians, Cucculanus longispiculum, Cucullanus minutu s, Contracaecum sp., Anisakis simplex and Cristitectus congeri, the cestode s Grillotia sp, and Scolex pleuronectis, and the acanthocephalan Acanthocep haloides propinquus were recorded from 251 conger eels from the Muros and A rousa estuaries, north-west Spain. Several species were useful as tags and showed that conger eels in both estuaries and also on the continental shelf belong to separate populations. The nematode C. congeri shows a distributi on pattern indicating that the trophic chains involving the conger eel in e ach estuary are probably different. The species composition and abundance o f the nematode, cestode and acanthocephalan fauna of Conger conger on the n orth-west Spanish coast may depend more on population isolation and variati ons in trophic chains between the sites studied than on the particular envi ronmental conditions of the sites. (C) 2000 The Fisheries Society of the Br itish Isles.