Acipenser oxyrinchus ssp. oxyrinchushttp://dx.doi.org/10.2305/IUCN.UK.2006.RLTS.T243A13046213.en
|Scientific Name:||Acipenser oxyrinchus ssp. oxyrinchus|
|Species Authority:||Mitchill, 1815|
|Red List Category & Criteria:||Near Threatened ver 3.1|
|Assessor(s):||St. Pierre, R. (U.S. Fish & Wildlife Service)|
|Reviewer(s):||St. Pierre, R. & Pourkazemi, M. (Sturgeon Red List Authority)|
In 1998, the U.S. Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) completed a comprehensive “Status Review of Atlantic Sturgeon” in response to a petition to list this species as threatened or endangered under the U.S. Endangered Species Act (ESA). The assessment found that, though Atlantic sturgeon populations are currently depressed from historic levels, breeding populations still exist in at least 14 Atlantic Coast rivers in the U. S. (Maine to Georgia) and several more in Canada (St. Lawrence, St. John). The number of mature individuals in this range-wide population was not estimated but most likely it numbers considerably more than 10,000. Area of occupancy is very large (>1,500 river km spread over 3,000 km of coastline). Substantial sub-population mixing may occur, particularly as sub-adults, and re-colonization of seriously depleted stocks may occur from adjacent healthy populations.
Throughout the 20th century, sturgeon breeding habitats have been adversely impacted by dams, siltation, channel maintenance (dredging) and water pollution. Although habitat and water quality concerns still occur in several locations, the vast majority of formerly occupied habitats remain available to this species. Continued application of existing U. S. laws (e.g., Clean Water Act, Fish and Wildlife Coordination Act, etc.) should result in improvements sturgeon breeding and nursery habitats. With management measures in place the current population trend for Atlantic sturgeon is increasing.
A. o. oxyrinchus are widespread and several subpopulations could be considered relatively abundant. However, the subspecies is assessed as Near Threatened based on levels of past population declines and because of uncertainties about overall stock health and the lengthy time required for population recovery.
|Previously published Red List assessments:||
|Range Description:||A. o. oxyrinchus historically ranged along the Canadian and U.S. Atlantic Coast from Labrador to Florida. Though populations are currently depressed from historic levels, breeding populations still exist in at least 14 Atlantic Coast rivers in the U.S. (Maine to Georgia) and several more in Canada (St. Lawrence, St. John).|
Native:Canada (New Brunswick, Newfoundland I, Nova Scotia, Prince Edward I., Québec); United States (Connecticut, Delaware, Florida, Georgia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, North Carolina, Rhode Island, South Carolina, Virginia)
|FAO Marine Fishing Areas:||
Atlantic – northwest; Atlantic – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Atlantic sturgeon were an important item of commerce to early American and Canadian colonists and large quantities of meat, roe, oil and isinglass were exported to Europe late 17th and 18th centuries. As flesh and roe (caviar) gained popularity in North American, the species was heavily exploited, particularly during several decades of the late nineteenth century. The largest fishery was in the Delaware River and Bay which by 1890 supported over 1,000 fishermen and produced 2,300 metric tons of sturgeon product. Several dozen other rivers supported sturgeon fisheries and by the late 1890s, total Atlantic Coast U.S. landings reached 3,200 mt. Severe over-fishing of mature sturgeon in the U.S. led to a crash of the stocks and harvest was reduced by over 90% by the early 1900s and 99% by the 1920s. Throughout the 1970s to mid-1980s, prior to declaration of fishing moratoria, annual U.S. harvest of Atlantic sturgeon ranged from 50–100 mt with most fish being taken from the Hudson River (NY), coastal New Jersey and the Carolinas (ASMFC 1990).
The number of mature individuals in the current population most likely numbers considerably more than 10,000.
|Current Population Trend:||Increasing|
|Habitat and Ecology:||The Atlantic sturgeon (A. o. oxyrinchus) is a large anadromous species that historically ranged along the Canadian and U.S. Atlantic Coast from Labrador to Florida. This subspecies is recorded to live for up to 60 years and reach a size of 4.3 m and 368 kg (Vladykov and Greely 1963), though most mature fish are considerably smaller. Spawning occurs in fresh or slightly brackish water when water temperatures reached 13–18˚C. Migrations into coastal tidal rivers begin as early as February in the southern portion of the range and continue through June and July in northernmost waters. In the mid-Atlantic area, Atlantic sturgeon males mature at 6–10 years and females at 10–20 years (ASMFC 1990). Maturation occurs earlier in southern waters and later in Canada. Spawning periodicity ranges from 2–6 years. Based on tagging studies ocean migrations of up to 1,450 km have been recorded (Dovel and Berggren 1983).|
|Major Threat(s):||Competition, predation, diseases and parasites were evaluated in the 1998 status review by USFWS-NMFS and determined not to be limiting factors for Atlantic sturgeon stocks. Throughout the 20th century, sturgeon breeding habitats have been adversely impacted by dams, siltation, channel maintenance (dredging) and water pollution. Although habitat and water quality concerns still occur in several locations, the vast majority of formerly occupied habitats remain available to this species. Continued application of existing U.S. laws (e.g., Clean Water Act, Fish and Wildlife Coordination Act, etc.) should result in improvements sturgeon breeding and nursery habitats. With management measures in place the current population trend for Atlantic sturgeon is increasing.|
All U.S. Atlantic sturgeon fisheries have been closed since 1997. Canada maintains active commercial fisheries in the St. Lawrence River (Quebec) for subadults of A. o. oxyrinchus, and in the Saint John River (New Brunswick) for larger fish. Also, a single fisherman is licensed on the Shubenacadie River in Nova Scotia. The St. Lawrence fishery was limited in 1997 to a quota of 6,015 fish - about 60 tons (Caron and Trembly 1997). Other regulations here include a maximum size limit of 1.5 m during a season extending from 1 May to 30 September.
Peak landings on the Saint John River were 44 metric tones (mt) in 1988 but have declined in recent years to 10–14 mt. Only nine licensed fishermen remained in the St. John fishery in 1997. They were authorized to fish no more than 2,800 m of gill net with minimum mesh size of 33 cm. Minimum allowable size of sturgeon on the St. John is 120 cm and the season is closed during 1–30 June to protect spawners. Canadian authorities have expressed to U.S. authorities that these harvest levels are sustainable and do not damage the stocks (USFWS and NMFS 1998). A private aquaculture activity also occurs in New Brunswick with eggs and progeny produced from wild-caught adult sturgeon. Except for a few hundred live juveniles, most international trade in A. o. oxyrinchus in the late 1990s has been meat (2–34 mt/year) from Canada to the U.S. (CITES data).
No commercial or sport fishing for Atlantic sturgeon is allowed in territorial waters of the U.S. Atlantic Coast. The management authority for this species is the Atlantic States Marine Fisheries Commission and their amendment to the 1990 Fishery Management Plan (ASMFC 1998) requires (1) no possession allowed in the 15 Atlantic states until at least 20 year-classes reach breeding age (30–40 years); (2) annual reporting of by-catch and by-catch mortality; (3) urges habitat monitoring and improvements as well as research and genetics analysis; and (4) places certain restrictions on sturgeon culture for market production and restocking. In addition to the ASMFC action, the Secretary of Commerce has closed all U.S. Atlantic coastal EEZ waters to harvest of Atlantic sturgeon.
The recent USFWS-NMFS joint status review for Atlantic sturgeon determined that listing this species as threatened or endangered under the U.S. ESA is not warranted at this time. Atlantic sturgeon are widespread and several subpopulations could be considered relatively abundant. However, because of uncertainties about overall stock health and the lengthy time required for population recovery, USFWS has designated Atlantic sturgeon as a "candidate species" for possible future ESA listing and NMFS lists it as a "species of concern".
|Citation:||St. Pierre, R. (U.S. Fish & Wildlife Service). 2006. Acipenser oxyrinchus ssp. oxyrinchus. The IUCN Red List of Threatened Species 2006: e.T243A13046213. http://dx.doi.org/10.2305/IUCN.UK.2006.RLTS.T243A13046213.en . Downloaded on 08 October 2015.|