Sturgeon Atlantic

Acipenser oxyrinchus

OTHER NAMES

sturgeon, common sturgeon, sea sturgeon, Albany beef; French: esturgeon noir d'Amerique.

Distribution. This species ranges along the northwestern and the western Atlantic coast in North America from the Hamilton River in Labrador, Canada, to northeastern Florida. It is currently more populous in the Hudson River, New York, than in other parts of its range, although it is not abundant there.

Habitat. The habitats of Atlantic sturgeon are primarily the estuaries and bays of large rivers and deep pools of rivers when inland; in the ocean they inhabit shallow waters of the continental shelf.

The Atlantic sturgeon is a member of the Acipenseridae family of sturgeon and primarily a fish of the East Coast of North America. It has been used as a high-quality food fish and as a source of caviar since colonial days; it was so abundant in portions of its range that in 1675, canoeists in Delaware Bay were warned to beware of 14- to 18-foot sturgeon that floated like submerged logs in tidal tributaries.

Like many other sturgeon, the Atlantic sturgeon is anadromous, living much of its life in brackish or saltwater and spawning in freshwater rivers. This species and other sturgeon are relatively slow growing and mature late in life, making them vulnerable to overexploitation. Dam construction, water pollution, and other changes in habitat, in addition to commercial overfishing, caused continued declines throughout the twentieth century. The Atlantic sturgeon is a threatened species today.

There is virtually no sportfishery for Atlantic sturgeon, due to their low numbers and harvest restrictions. If populations were high, a recreational fishery would undoubtedly exist, similar to that for the white sturgeon in the Pacific Northwest. A limited directed commercial fishery still occurs for them, however, and a large portion of the landings are bycatch, due to developing ocean fisheries. These practices continue to threaten recovery efforts.

Most fisheries are now closed in compliance with the Atlantic sturgeon management plan of the Atlantic States Marine Fisheries Commission, but the outlook is still poor, and much needs to be done to bring about even a modest growth in populations.

Identification. The Atlantic sturgeon is dark brown or olive green with a white belly. The head is protractile and has a long flat snout with four barbels on the underside. Five rows of scutes (bony, scalelike plates) extend along the length of the body; one is along the back, and two each are along the sides and the belly. The centers of the scutes along the back and the sides are light, making them stand out in contrast to the darker surrounding color. These scutes are set extremely close together, and the bases of most overlap. The Atlantic sturgeon is distinguished from the similar shortnose by a longer snout.

Size/Age. Atlantic sturgeon may live as long as 60 years. They can attain a size of 14 feet and weigh more than 800 pounds. An 811-pounder is the largest known specimen. Fish exceeding 200 pounds, however, are rare today.

Life history/Behavior. Spawning migrations to freshwater last from late winter through early summer, occurring later in the year at higher latitudes. Although it matures late in life, the Atlantic sturgeon is highly fecund, with total egg production proportional to its body size (a 9-foot, 245-pound female, about 30 years old, produced 61 pounds of roe). Nevertheless, it has a low reproduction rate, as females spawn only once every 3 to 5 years, and juvenile mortality is high. Furthermore, females do not mature until ages 7 to 10 in the southern part of their range and ages 22 to 28 in the most northern part of their range; these late maturations complicate management efforts, especially because the fish are at sea for long periods, until they return to natal waters to spawn.

Juvenile sturgeon remain in freshwater for their first summer of life and then migrate to deeper, more brackish water in winter. The juveniles migrate to and from freshwater for a number of years before joining the adult migration pattern. Tagging studies have demonstrated that Atlantic sturgeon migrate extensively both north and south of their natal river systems.

Food and feeding habits. Juveniles and adults are bottom-feeding scavengers, consuming a variety of crustaceans, bivalves, and worm prey, as well as insect larvae and small fish.

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