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Fishes can broadly be split up into four groups according to feeding habits. Some fishes eat algae, but none of those can be found in Icelandic waters
The most abundant species in Icelandic waters are the zooplankton feeding species, dominated by two pelagic species, capelin and herring; they mostly eat copepods. Other abundant species, such as redfishes, blue whiting, and sandeels feed predominantly on euphausids but also on other zooplankton and benthic invertebrates to some extent. These fishes are themselves important food for larger fish species.
The main benthic feeding fish species, or groups, are haddock, catfishes, skates and flatfishes. Most of these also eat other fishes, mostly capelin or sandeel when available.
Higher in the trophic level are the piscivorous fishes, dominated by cod in warmer waters and Greenland halibut and Greenland shark in colder seas. Other species at this trophic level are mostly gadoids, such as saithe, whiting, and lings, but other less numerous groups are Atlantic halibut, monkfish (, and spiny dogfish. In general, species in this group eat mostly small invertebrates when small, and then gradually shift to other fish when fully grown.
About 340 fish species have been recorded within the Icelandic EEZ. Thereof 62 have been found in Eyjafjörður. The reason that more fishes have not been found is that many of the fishes are deep water or oceanic species that are never seen close to land.
If we only look at shallow water species there have in fact very many species been found in Eyjafjörður. Northern Iceland is at a boundary of two ecological zone, the cold temperate and Arctic. Thus species from both of these zones can be found there. Polar cod, eelpouts, Greenland shark and Greenland halibut are among the fishes that are from the north. Examples of species from the temperate zone are mackerel, tusk, dealfish and monkfish. However none of those species are common in Eyjafjörður, in fact many of them are just stragglers. The oceanic conditions in Eyjafjörður are just too variable for these species
A few species do however thrive where these two zones occur, the cold and the warm. These are the most common species in Eyjafjörður and the ones that live there permanently. The northern Icelandic waters are especially important for some of the most important exploited species in Icelandic waters. Fjords and bays are important as rearing grounds for cod, haddock, saithe, herring and lumpsucker and capelin juveniles are abundant in oceanic waters outside the fjords. The largest spawning areas for these species are in the warmer waters south and west of Iceland but juveniles drift north with currents. Other common species in Eyjaförður are redfishes, starry ray, long rough dab, dab and plaice. |
Ýsa (Mynd: Erlendur Bogason)
Ýsa (Mynd: Erlendur Bogason)
Skötuselur (Mynd: Erlendur Bogason)
Skötuselur (Mynd: Erlendur Bogason)
Hlýri (Mynd: Erlendur Bogason)
Hlýri (Mynd: Erlendur Bogason)
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