Our Neighborhood's Biodiversity Map

* Please click the continent to see the endangered species of our neighborhood.
Acipenser oxyrinchus PAQ * To See the original image, please click the image
Shared by : Arushi Madan (UK)
Region : Europe
Status : CR (Critically Endangered)
The European sea sturgeon also known as Atlantic Sturgeon or common sturgeon is among the oldest fish species in the world. The Atlantic sturgeon is a long-lived, estuarine dependent, anadromous fish. The species is also known for its occasional 'leaping' behavior, during which the fish will emerge completely out of the water in a forceful motion that can be hazardous to anything unlucky enough to be struck. The exact reason why sturgeon leap is not clear, although it is believed that leaping is a form of group communication.
Appearance and Vital Statistics:
Weight: up to 800 pounds (370 kg) Length: up to 14 feet (4.3 m)
Appearance: bluish-black or olive brown with paler sides and a white belly they have 5 major rows of "scutes" Lifespan: 60 years Diet: crustaceans, worms, and mollusks Behavior: upriver migrations in spring in spawn also some smaller fall spawning migrations The wedge-shaped head of the European sea sturgeon ends in a long point. There are many sensitive barbels on the facial area. The dorsal fins are located very far back on the body. Five longitudinal lines of large osseous plates are found on the body of the fish. The stomach is yellow and the back is a brownish grey.
Distribution and habitat:
Native: France Regionally extinct: Belgium Denmark Germany Italy Netherlands Norway Portugal Spain Tunisia United Kingdom.
Range: The range of the Atlantic sturgeon extends from New Brunswick, Canada, to the eastern coast of Florida, United States. A disjunct population occurs in the Baltic region of Europe (currently only through a reintroduction project). They are found on the coasts of Europe, except in the northernmost regions and the Baltic region, and have rarely even been known to cross the Atlantic Ocean to the coasts of North America. Like many other sturgeons, they spawn in the rivers inland from the coast. Despite their estimated range of distribution, they have become so rare that they only breed in the Garonne river basin in France. Anadromous (spends at least part of its life in salt water and returns to rivers to breed).
Causes/ Threats
• Overharvest led to wide-spread declines in Atlantic sturgeon abundance.
• Commercial fishing/ overfishing
• Water pollution.
• "bycatch" of sturgeon in fisheries targeting other species
• Habitat degradation and loss from various human activities such as dredging, dams, water withdrawals, and other development
• Habitat impediments including locks and dams (e.g., Cape Fear and Santee-Cooper Rivers)
• Ship strikes (e.g., Delaware and James Rivers).
• Although there are no known diseases threatening Atlantic sturgeon populations, there is concern that non-indigenous sturgeon pathogens could be introduced through aquaculture operations.
• Originally, the Atlantic sturgeon was considered a worthless fish. Its rough skin would often rip nets, keeping fishermen from catching more profitable fish. Sturgeon were one of the types of fish harvested at the first North American commercial fishery, and were the first cash "crop" harvested in Jamestown, Virginia. Other fisheries along the Atlantic coast harvested them for use as food, a leather material used in clothing and bookbinding, and isinglass, a gelatinous substance used in clarifying jellies, glues, wines and beer. However, the primary reason for catching sturgeon was the high-quality caviar that could be made cheaply from its eggs, called black gold by watermen.
Conservation/Restoration Efforts:
The Atlantic sturgeon is managed under a Fishery Management Plan implemented by the Atlantic States Marine Fisheries Commission (ASMFC). In 1998, the ASFMC instituted a coast-wide moratorium on the harvest of Atlantic sturgeon, which is to remain in effect until there are at least 20 protected age classes in each spawning stock (anticipated to take up to 40 or more years). ASMFC's Atlantic sturgeon Fishery Management Plan also includes measures for preservation of existing habitat, habitat restoration and improvement, monitoring of bycatch and stock recovery, and breeding/stocking protocols. NMFS followed the ASMFC moratorium with a similar moratorium for Federal waters. An ongoing in situ conservation programme is in place. Ex-situ conservation is carried out in France and Germany. Bern Convention Action Plans have been developed, while National Action Plans are to come. Restocking: Conservation projects involving this species include reintroductions based on specimens from aquaculture with the first releases in 1995. For example, some 50 sturgeons were reintroduced in the Rhine near Nijmegen in 2012.
There is a fisheries awareness programme co-ordinated between National Fishermen Associations in Atlantic North Sea and WWF. Management of the species is largely based on the restriction of fishing of the species. This helps limit fishing mortalities of sturgeon to bycatch. At the beginning of the 19th century, these fish were used extensively to produce caviar, but have been a protected species in Europe since 1982. Sources: earthsendangered.com http://www.iucnredlist.org

Sources :
Image Credit : Flickr


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