Biotic relationships of Illex coindetii and Todaropsis eblanae (Cephalopoda, Ommastrphidae) in the Northeast Atlantic: Evidence from parasites

• Published in: Sarsia
• Main Authors: Pascual, Santiago, Gonzalez, Angel, Arias, Christina, Guerra, Angel
• Format: Article in Journal/Newspaper
• Language: English
• Published: Taylor & Francis 1996
• Subjects: Northeast Atlantic
• Online Access: https://oceanrep.geomar.de/id/eprint/50768/; https://oceanrep.geomar.de/id/eprint/50768/1/2922.pdf; https://doi.org/10.1080/00364827.1996.10413624

Parasites were collected from 1,200 short-finned squid (Illex coindetii, Todaropsis eblanae) caught as by-catch in a multispecies trawling fishery in the northwest Spanish Atlantic waters in 1992-1993. Parasites found included six species of helmiths, three tetraphyllidean cestodes (Phyllobothrium sp., Pelichnibothrium speciosum, Dinobothrium sp.), two trypanorhyllidean cestodes (Nybelinia yamagutii, Nybelinia lingualis), and one ascarioid nematode (Anisakis simplex B). Two of these parasites (Phyllobothrium sp., A. simplex B) which could be recognised as component species, were used in analyses of host-parasite relationships. Levels of infection varied significantly with host size or stage of maturation for both squid species. Regional variation in infection level seems attributable to geopgraphical variation in variability of prey, discreteness and movements of host populations and to size or age-related changes in the prey selection of their host. Parasite evidences suggest that both ommastrephid squids are sympatric species sharing similar econiches, and serve as diet for large top predators (selachians and marine mammals) of Northeast Atlantic. Parasites may also be useful as an indirect indicator of the migratory habits of the squid.