Crangon septemspinosa Say, 1818, jap coast of United States.
OTHER COMMON NAMES
English: Salt-and-pepper shrimp, sand shrimp; French: Crevette de sable, crevette grise.
Length to three in (75 mm). First leg is subchelate. Body is considerably dorsoventrally compressed; rostrum small. Color sometimes grayish with darkish and light-weight speckling, matching the sediment in its habitat.
Northern Gulf of Saint Lawrence to jap Florida; Alaska.
Typically discovered from 0 to 115 ft (0-35 m), however collected from waters as deep as 1,460 ft (450 m). Occurs in all kinds of habitats however most plentiful on mud flats, sand, and in eelgrass beds; very tolerant of low salinities.
Remains buried within the sediment within the daytime, rising at night time to search prey on and above the underside. Populations seem to migrate offshore to deeper water within the winter, probably to keep away from extraordinarily chilly temperatures.
FEEDING ECOLOGY AND DIET
Primarily a predator, feeding on mysids, amphipods, worms, and mollusks. May additionally prey on newly-settled flatfish. Food is usually swallowed complete and shortly floor up within the gastric mill of the cardiac abdomen. The bay shrimp is understood to scavenge opportunistically and also will eat diatoms, algae, and detritus.
Studies of carefully associated species of Crangon reveal that almost all people are protandric hermaphrodites (maturing first as males after which altering to feminine as they get bigger) whereas some “primary females” stay the identical intercourse all through life. Eggs are brooded on the pleopods; giant egg-bearing females migrate into estuaries in spring and release their larvae, that are carried out to sea, whereas smaller females release their larvae within the late fall. Larvae move via seven zoeal levels earlier than settling out; these hatched within the spring migrate to shallow areas the place they develop quickly.
Not listed by the IUCN. One of probably the most plentiful shrimps within the northwestern Atlantic, and an vital prey merchandise for a lot of species. Population trends not identified.
SIGNIFICANCE TO HUMANS
Although often fished prior to now, this species is taken into account too small to be worthwhile for human.