Observations of a wild polar bear (Ursus maritimus) successfully fishing arctic charr (Salvelinus alpinus) and fourhorn sculpin
The largest denticles occur in the middle of the scutes and tubercles, with smaller ones towards the margins; in the fourhorn sculpin
, however, the largest denticles occur at the margins.
Vertebral deformities and physiological effects in fourhorn sculpin
(Myoxocephalus quadricornis) after long-term exposure to a simulated heavy metal-containing effluent.
The species of Lake Michigan fish used in the creation of these plots were lake trout, yellow perch, whitefish, white and long-nose sucker, and coho and chinook salmon, as well as several prey species such as bloater, alewife, fourhorn sculpin
, and rainbow smelt (De Vault et al.
As to the number of specimens collected, the yield should be density-dependent at a given time and place, with the nets very likely catching more individuals of abundant species (such as the ninespine stickleback and fourhorn sculpin) that are numerically important in nearshore areas.
75 Fourhorn sculpin (Myoxocephalus quadricornis) * 255(7) Arctic sculpin (Myoxocephalus scorpioides) * 3 Shorthorn sculpin (Myoxocephalus scorpius) 11(1) Ribbed sculpin (Triglops pingelii) * 1 Tubenose poacher (Pallasina barbata) 1 Liparis sp.
The three species, each the only representative of its genus in the Baltic Sea, are the fourhorn sculpin
Triglopsis quadricornis (Linnaeus, 1758), the shorthorn sculpin Myoxocephalus scorpius (Linnaeus, 1758) and the longspined bullhead Taurulus bubalis (Euphrasen, 1786).
The brackish lagoons in the Beaufort Sea are dominated by anadromous species such as whitefishes (e.g., Arctic cisco and least cisco) (Craig, 1984), whereas the marine nearshore environment on the seaward side of the barrier islands is more like the northeastern Chukchi Sea and is dominated by Arctic cod, capelin, and fourhorn sculpin
(Myoxocephalus quadricornis) (Griffiths et al., 1977; Craig et al., 1985; Jarvela and Thorsteinson, 1999).
were abundant at all times, but were not retained and the catch was not quantified.
Arctic cod (Boreogadus saida), fourhorn sculpin
(Myoxocephalus quadricornis), and arctic flounder (Liopsetta glacialis) are the most abundant marine species.
We analyzed abundance indices, as logetransformed catch-per-unit-effort (CPUE), of four marine species (arctic cod, Boreogadus saida; fourhorn sculpin
, Myoxocephalus quadricornis; arctic flounder, Pleuronectes glacialis; saffron cod, Eleginus gracilis); two freshwater species (round whitefish, Prosopium cylindraceum; arctic grayling, Thymallus arcticus); and the anadromous rainbow smelt, Osmerus mordax, to determine whether there were increases in the abundances of marine species and declines in anadromous and freshwater species.
Food of alewives, yellow perch, spottail shiners, trout-perch, and slimy and fourhorn sculpins
in southeastern Lake Michigan.