Parasites as biological tags of marine, freshwater and anadromous fishes in North America from the tropics to the Arctic

Abstract

Parasites have been considered as natural biological tags of marine fish populations in North America for almost 75 years. In the Northwest Atlantic, the most studied species include Atlantic cod (Gadus morhua), Atlantic herring (Clupea harengus) and the redfishes (Sebastes spp.). In the North Pacific, research has centred primarily on salmonids (Oncorhynchus spp.). However, parasites have been applied as tags for numerous other pelagic and demersal species on both the Atlantic and Pacific coasts. Relatively few studies have been undertaken in the Arctic, and these were designed to discriminate anadromous and resident salmonids (Salvelinus spp.). Although rarely applied in fresh waters, parasites have been used to delineate certain fish stocks within the Great Lakes-St Lawrence River basin. Anisakid nematodes and the copepod Sphyrion lumpi frequently prove useful indicators in the Northwest Atlantic, while myxozoan parasites prove very effective on the coast and open seas of the Pacific Ocean. Relative differences in the ability of parasites to discriminate between fish stocks on the Pacific and Atlantic coasts may be due to oceanographic and bathymetric differences between regions. Molecular techniques used to differentiate populations and species of parasites show promise in future applications in the field.

Parasites as Biological Tags for Stock Discrimination of Beaked Redfish (Sebastes mentella): Parasite Infra-Communities vs. Limited Resolution of Cytochrome Markers

“…gave the strongest evidence of an effect to the model. Anisakids are the most commonly used parasites for stock differentiation as they are abundant and due to their large size easy to detect [ 18 , 68 , 69 ], which was confirmed in this study. The calculated probabilities to assign the correct origin of a fish according to the presence of an identified parasite species showed that a fish with C .…”

“…When choosing biological tags to separate fish stocks, genetic structure of parasite populations potentially identify host stock structure or host migration patterns more accurately than classic parasite abundance measurements [ 69 ]. Commonly used markers for population structure analyses are mitochondrial genes such as cox2 (cytochrome oxidase c) with their high substitution rate and maternal inheritance [ 2 ].…”

Parasitofauna of Five Freshwater Fishes in a Nigerian Freshwater Ecosystem

“…The fish were sectioned and the alimentary canal, liver, kidney, swim bladder and spleen examined for endoparasites. The excised gastrointestinal tract was carefully sectioned into portions such as oesophagus, intestine and rectum and each portion was then cut open, washed in Petri dish with 0.1% sodium chloride solution and further rinsed with 0.1% sodium bicarbonate to enhance parasite search (Paperna, 1996;Marcogliese, 2011). Trematode cysts from the muscle were manually teased to release the metacercariae, which were (Ezemonye et al, 2008) fixed in hot alcohol-formal-acetate (AFA) and preserved in 70% ethyl alcohol.…”

“…Cestodes were stained with aqueous acetocarmine solution (Khalil, 1971). The acanthocephalans were placed in a refrigerator overnight in Petri dishes containing 0.1% sodium chloride solution (this caused the proboscis of the acanthocephalans to extrude) and then preserved in 70% ethyl alcohol (Marcogliese, 2011). Leeches collected from fishes were kept in mentholic water to ensure complete relaxation before fixation in 95% ethyl alcohol (Khalil, 1971).…”

Was Fischparasiten über ihre Umwelt preisgeben

“…diese mit der Nahrung aufnehmen. Sowohl in limnischen als auch in brackigen und marinen Lebensräumen ließen sich so unterschiedliche Fischpopulationen mittels ihrer ortstypischen Parasitenfauna nachweisen . Ebenso behalten Fische bei Wechseln zwischen Süß‐ und Salzwasserhabitaten (und vice versa ) im Zuge von Laichwanderungen einen Teil der Parasitenarten ihres Herkunftsgebietes.…”