Atlantic sturgeon | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Acipenseriformes |
Family: | Acipenseridae |
Genus: | Acipenser |
Species: | |
Subspecies: | A. o. oxyrinchus |
Trinomial name | |
Acipenser oxyrinchus oxyrinchus Mitchill, 1815 |
The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) is a member of the family Acipenseridae, and, along with other sturgeon, it is sometimes considered a living fossil. The Atlantic sturgeon is one of two subspecies of A. oxyrinchus , the other being the Gulf sturgeon (A. o. desotoi). The main range of the Atlantic sturgeon is in eastern North America, extending from New Brunswick, Canada, to the eastern coast of Florida, United States. A disjunct population occurs in the Baltic region of Europe (today only through a reintroduction project). The Atlantic sturgeon was in great abundance when the first European settlers came to North America, but has since declined due to overfishing, water pollution, and habitat impediments such as dams. [3] It is considered threatened, endangered, and even locally extinct in many of its original habitats. The fish can reach 60 years of age, 15 ft (4.6 m) in length and over 800 lb (360 kg) in weight. [4]
Rather than having true scales, the Atlantic sturgeon has five rows of bony plates known as scutes. Specimens weighing over 800 lb and nearly 15 ft in length have been recorded, but they typically grow to be 6–8 ft (1.8–2.4 m) and no more than 300 lb (140 kg). Its coloration ranges from bluish-black and olive green on its back to white on its underside. It has a longer snout than other sturgeons and has four barbels at the side of its mouth. [5]
Atlantic sturgeon under six years of age stay in the brackish water where they were born before moving into the ocean. They may be 3–5 ft (0.91–1.52 m) long at this stage. In areas where shortnose sturgeon are also present, the adults of that species can be, and historically were for centuries, confused with immature Atlantic sturgeon. When mature, they travel upstream to spawn. The females may lay 800,000 to 3.75 million eggs in a single year, doing so every two to six years. After laying their eggs, females travel back downstream, but males may remain upstream after spawning until forced to return downstream by the increasingly cold water. They may even return to the ocean, where they stay near the coastline.[ citation needed ]
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. [6] [7] The exact reason why sturgeon leap remains unknown, although some scholars believe leaping is a form of group communication. In one study, of a population of the species in the Suwannee river in northwestern Florida, leaping behavior was found to vary seasonally, with the highest frequency of occurrence in June. [8]
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.[ citation needed ] 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. In the late 19th century, seven million pounds of sturgeon meat were exported from the US per year. Within years, however, that amount dropped to 22,000 pounds. The number later rose to about 200,000 pounds a year in the 1950s.[ citation needed ]
In February 2012, the Atlantic sturgeon was listed by the National Oceanic and Atmospheric Administration Fisheries Service under the Endangered Species Act (ESA). [9] Four distinct population segments (DPSs) were listed as endangered (New York Bight, Chesapeake Bay, Carolina, and South Atlantic) while one DPS was listed as threatened (Gulf of Maine). [10] As of this writing (July 22, 2015) there are concerns that the construction of the bridge to replace the Tappan Zee connecting Rockland County to Westchester County in New York, in the Hudson River, may impact the sturgeon's ecological stability. [11]
The American Fisheries Society considers the fish as threatened throughout its entire range, although it is believed to no longer inhabit the full range it once did. In the Chesapeake watershed, the James River in Virginia is one of the last confirmed holdouts for that region's population. In May 2007, a survey captured 175 sturgeon in the river, with 15 specimens exceeding 5 ft (1.5 m). [12] A bounty-based survey of live Atlantic sturgeon in Maryland's portion of the bay found a high number of captures reported in 2005–06. [13] [14]
In 2016, the National Marine Fisheries Service considered designating sixteen rivers as endangered habitat, which would require more attention to be given to uses of the rivers that affect the fish. [15] Then in 2018, NMFS actually mapped a total of thirty-one critical river habitats along the United States' Atlantic shores. [16]
The now nearly extinct sturgeon population in the Baltic Sea area belongs to the Atlantic sturgeon A. oxyrinchus rather than to the European species A. sturio as had been thought. A. oxyrinchus migrated to the Baltic about 1300 years ago and displaced the native A. sturio. [17]
The last known specimen of the Atlantic sturgeon in the Baltic region was caught in 1996 near Muhumaa in Estonia. It was 2.9 m (9.5 ft) long, weighed 136 kg (300 lb), and was estimated to be about 50 years old. [18]
A German-Polish project was underway in 2009 to reintroduce the sturgeon into the Baltic by releasing specimens caught in the Canadian Saint John River into the Oder, a river at the border between Germany and Poland where the species once spawned. [19] The project expanded in 2013 to include Estonia, where one-year-old juveniles were released into the Narva River. [20]
IUCN: Vulnerable [1]
CITES: Appendix II [21]
The American Fisheries Society considers it endangered in all stream systems except conservation-dependent in the Hudson, Delaware, and Altamaha Rivers.[ citation needed ]
The Atlantic sturgeon of the Delaware River are listed under the ESA as part of the New York Bight distinct population segment (DPS), [22] [23] which includes all Atlantic sturgeon that spawn in watersheds draining to coastal waters from Chatham, Massachusetts, to the Delaware-Maryland border on Fenwick Island, [23] : 5881 the Chesapeake Bay DPS, the Carolina DPS and the South Atlantic DPS, while the Gulf of Maine DPS is listed threatened. [22] [23] Canadian-origin populations are not currently listed under the U.S. ESA. [22] NMFS believes fewer than 300 spawning adults are in the Delaware River population; just over 100 years ago the estimated population was 180,000 spawning adult females.[ citation needed ]
Atlantic sturgeon are now a threatened species. Management of the species is largely based on the restriction of fishing of the species. This helps limit fishing mortalities of sturgeon to bycatch. [24]
Atlantic herring is a herring in the family Clupeidae. It is one of the most abundant fish species in the world. Atlantic herrings can be found on both sides of the Atlantic Ocean, congregating in large schools. They can grow up to 45 centimetres (18 in) in length and weigh up to 1.1 kilograms (2.4 lb). They feed on copepods, krill and small fish, while their natural predators are seals, whales, cod and other larger fish.
Sturgeon is the common name for the 28 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the Late Cretaceous, and are descended from other, earlier acipenseriform fish, which date back to the Early Jurassic period, some 174 to 201 million years ago. They are one of two living families of the Acipenseriformes alongside paddlefish (Polyodontidae). The family is grouped into four genera: Acipenser, Huso, Scaphirhynchus, and Pseudoscaphirhynchus. Two species may be extinct in the wild, and one may be entirely extinct. Sturgeons are native to subtropical, temperate and sub-Arctic rivers, lakes and coastlines of Eurasia and North America. A Maastrichtian-age fossil found in Morocco shows that they also once lived in Africa.
The Atlantic wolffish, also known as the seawolf, Atlantic catfish, ocean catfish, devil fish, wolf eel, woof or sea cat, is a marine fish of the wolffish family Anarhichadidae, native to the North Atlantic Ocean. The numbers of the Atlantic wolffish in US waters are rapidly being depleted, most likely due to overfishing and bycatch, and it is currently a Species of Concern according to the U.S. National Oceanic and Atmospheric Administration's National Marine Fisheries Service.
The Nassau grouper is one of the large number of perciform fishes in the family Serranidae commonly referred to as groupers. It is the most important of the groupers for commercial fishery in the West Indies, but has been endangered by overfishing.
The eulachon, or the candlefish, is a small anadromous species of smelt that spawns in some of the major river systems along the Pacific coast of North America from northern California to Alaska.
The kaluga, also known as the river beluga, is a large predatory sturgeon found in the Amur River basin from Russia to China and near Hokkaido in Japan. With a maximum size of at least 1,000 kg (2,205 lb) and 5.6 m (18 ft), the kaluga is one of the biggest of the sturgeon family. Like the slightly larger beluga, it spends part of its life in salt water. Unlike the beluga, this fish has 5 major rows of dermal scutes and feeds on salmon and other fish in the Amur with its nail like teeth in its jaws. They have gray-green to black backs with a yellowish green-white underbelly.
The lake sturgeon, also known as the rock sturgeon, is a North American temperate freshwater fish, one of about 25 species of sturgeon. Like other sturgeons, this species is a bottom feeder and has a partly cartilaginous skeleton, an overall streamlined shape, and skin bearing rows of bony plates on the sides and back.
The Chinese sturgeon is a critically endangered member of the family Acipenseridae in the order Acipenseriformes. Historically, this anadromous fish was found in China, Japan, and the Korean Peninsula, but it has been extirpated from Korea, Japan, and most regions in China due to habitat loss and overfishing.
The European sea sturgeon, also known as the Atlantic sturgeon or common sturgeon, is a species of sturgeon native to Europe. It was formerly abundant, being found in coastal habitats all over Europe. Most specifically, they reach the Black and Baltic Sea. It is anadromous and breeds in rivers. It is currently a critically endangered species. Although the name Baltic sturgeon sometimes has been used, it has now been established that sturgeon of the Baltic region are A. oxyrinchus, a species otherwise restricted to the Atlantic coast of North America.
White sturgeon is a species of sturgeon in the family Acipenseridae of the order Acipenseriformes. They are an anadromous (migratory) fish species ranging in the Eastern Pacific; from the Gulf of Alaska to Monterey, California. However, some are landlocked in the Columbia River Drainage, Montana, and Lake Shasta in California, with reported sightings in northern Baja California, Mexico.
The shortnose sturgeon is a small and endangered species of North American sturgeon. The earliest remains of the species are from the Late Cretaceous Period, over 70 million years ago. Shortnose sturgeons are long-lived and slow to sexually mature. Most sturgeons are anadromous bottom-feeders, which means they migrate upstream to spawn but spend most of their lives feeding in rivers, deltas and estuaries. The shortnose sturgeon is often mistaken as a juvenile Atlantic sturgeon because of its small size. Prior to 1973, U.S. commercial fishing records did not differentiate between the two species: both were reported as "common sturgeon", although it is believed based on sizes that the bulk of the catch was Atlantic sturgeon. The shortnose is distinguishable from the Atlantic sturgeon due to its shorter and rounder head.
The green sturgeon is a species of sturgeon native to the northern Pacific Ocean, from China and Russia to Canada and the United States.
The bocaccio rockfish is a species of marine ray-finned fish belonging to the subfamily Sebastinae, the rockfishes, part of the family Scorpaenidae, It is found in the northeast Pacific Ocean.
The Gulf sturgeon is a subspecies of sturgeon that lives in the Gulf of Mexico and some rivers draining into it. The Gulf sturgeon was first recognized as a separate subspecies in 1955. The nominate subspecies is the Atlantic sturgeon, A. o. oxyrinchus. The Gulf sturgeon is listed as threatened under the United States Endangered Species Act, having been listed in 1991. Critical habitat, reflecting the range of the subspecies deemed essential for its continued survival, has been designated. The historical range is thought to have been from the Suwannee River on the western coast of Florida to the Mississippi River, and marine waters of the central and eastern portions of the Gulf of Mexico. Three sturgeon species in genus Scaphirhynchus share river territory with the Gulf sturgeon; none of the other sturgeon species is anadromous.
Dabry's sturgeon, also known as the Yangtze sturgeon, Changjiang sturgeon and river sturgeon, is a species of fish in the sturgeon family, Acipenseridae. It is endemic to China and today restricted to the Yangtze River basin, but was also recorded from the Yellow River basin in the past. It was a food fish of commercial importance. Its populations declined drastically, and since 1988, it was designated an endangered species on the Chinese Red List in Category I and commercial harvest was banned. It has been officially declared extinct in the wild by the IUCN as of July 21, 2022.
The Adriatic sturgeon is a species of fish in the family Acipenseridae. It is native to the Adriatic Sea and large rivers which flow in it of Albania, Greece, Italy, Montenegro, Croatia, Bosnia and Herzegovina and Slovenia. Specimens can be seen in several public aquarium, such the Milan Aquarium, Aquarium Finisterrae, Aquarium of the Po, and Oasis of Sant'Alessio in Lombardy.
Acipenser oxyrinchus is a species of sturgeon.
A distinct population segment (DPS) is the smallest division of a taxonomic species permitted to be protected under the U.S. Endangered Species Act. Species, as defined in the Act for listing purposes, is a taxonomic species or subspecies of plant or animal, or in the case of vertebrate species, a distinct population segment.
The Southern California Steelhead Distinct Population Segment (DPS) occurs from the Santa Maria River to the Tijuana River at the United States and Mexican Border in seasonally accessible rivers and streams. Steelhead in the Southern California Steelhead DPS, much like its relatives further north, requires sufficient flows in their natal streams to be able to return from oceans and lakes to spawn. Due to the extended periods of drought throughout their range, Southern California steelhead are most commonly seen during periods of increased rainfall, such as El Niño events. Declared federally endangered in 1997, the geographic range of the DPS when first listed extended from the Santa Maria River south to Malibu Creek. In 2002 steelhead were discovered in San Mateo Creek on the county line of Orange and San Diego counties. With this discovery the range of the DPS was extended to include Los Angeles, Orange, and San Diego counties.
The Alabama shad is an anadromous species of alosid fish endemic to the United States where it breeds in medium to large flowing rivers from the Mississippi River drainage to the Suwannee River, Florida, as well as some other Gulf coast drainages. The biology of this fish is little known but it has become increasingly rare. The International Union for Conservation of Nature rated it "near threatened" in 2020 and the United States National Marine Fisheries Service has listed it as a Species of Concern. A principal reason for its decline is thought to be the many locks and dams blocking access for the fish to up-river spawning grounds.
{{cite news}}
: CS1 maint: multiple names: authors list (link)