Main Ref. | Morrow, J.E., 1980 |
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Remarks | Occurs in cold brackish and moderately saline water near the coast (Ref. 27547); enters coastal rivers and may occur as far as 120 miles inland (Ref. 5723). Benthic (Ref. 58426). Movements are limited to short onshore-offshore seasonal movements and mass movements of fry into shallow water in autumn (Ref. 28908, 28910). Moreover, there are no migrations of large numbers; movement into freshwater and long distances up rivers are apparently undertaken by relatively few individuals at a time (Ref. 27547). Diurnal from November to April but is largely nocturnal the rest of the year (Ref. 28905). Feeds on small crustaceans, fishes (Ref. 4697, 4968, 27547) and molluscs (Ref. 58426). Move to deeper water in the spring, where they stay in summer (Ref. 35388). Subject to intense predation in shallow water by gulls, waterfowl and shorebirds. Also eaten by whitefish, Arctic Char, eelpouts and other Cottidae including other members of its own species (Ref. 58522). |
Marine - Neritic | Marine - Oceanic | Brackishwater | Freshwater | |
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Marine zones / Brackish and freshwater bodies |
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Substrate | |
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Substrate Ref. | |
Special habitats | |
Special habitats Ref. |
Ref. | Scott, W.B. and M.G. Scott, 1988 |
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Associations | schooling; |
Associated with | |
Association remarks | Parasites of the species include 1 monogenean, Gyrodactylus nainum; 1 trematode, Podocotyle atoman; 2 cestodes, Bothrimonus sturionis and Bothriocephalus scorpii; and 1 acanthocephalan, Echinorhynchus gadi (Ref. 5951). Territorial nest-builders with only the males defending the eggs until the pelagic larvae hatch (Ref. 27547, 94973); an ambush predator; relatively poor swimming ability make it susceptible to predation (Ref. 94973). Barring short onshore-offshore seasonal movements and mass movements of fry into shallow water in summer, there are no migrations of large numbers of fish (Ref. 27547, p. 208). |
Parasitism |
Feeding type | mainly animals (troph. 2.8 and up) |
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Feeding type Ref. | Morrow, J.E., 1980 |
Feeding habit | variable |
Feeding habit Ref. |
Estimation method | Original sample | Unfished population | Remark | ||
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Troph | s.e. | Troph | s.e. | ||
From diet composition | |||||
From individual food items | 3.85 | 0.62 | Trophic level estimated from a number of food items using a randomized resampling routine. | ||
Ref. |