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Sturgeon is the
common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...
for the 27 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the
Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...
, 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 Paddlefish (family Polyodontidae) are a family of ray-finned fish belonging to order Acipenseriformes, and one of two living groups of the order alongside sturgeons (Acipenseridae). They are distinguished from other fish by their titular elong ...
(Polyodontidae). The family is grouped into four genera: '' Acipenser'' (which is
paraphyletic In taxonomy, a group is paraphyletic if it consists of the group's last common ancestor and most of its descendants, excluding a few monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In ...
, containing many distantly related sturgeon species), '' Huso'', '' Scaphirhynchus,'' and '' Pseudoscaphirhynchus''. Two species ('' A. naccarii'' and '' A. dabryanus'') may be extinct in the wild, and one ('' P. fedtschenkoi'') may be entirely extinct. Sturgeons are native to subtropical, temperate and sub-Arctic rivers, lakes and coastlines of
Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelag ...
and
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...
. Sturgeons are long-lived, late-maturing fishes with distinctive characteristics, such as a heterocercal caudal fin similar to those of
shark Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachi ...
s, and an elongated, spindle-like body that is smooth-skinned, scaleless, and armored with five lateral rows of bony plates called scutes. Several species can grow quite large, typically ranging in length. The largest sturgeon on record was a beluga female captured in the
Volga Delta The Volga Delta is the largest river delta in Europe, and occurs where Europe's largest river system, the Volga River, drains into the Caspian Sea in Russia's Astrakhan Oblast, north-east of the republic of Kalmykia. The delta is located in the ...
in 1827, measuring long and weighing . Most sturgeons are anadromous bottom-feeders, which migrate upstream to spawn, but spend most of their lives feeding in
river delta A river delta is a landform shaped like a triangle, created by deposition of sediment that is carried by a river and enters slower-moving or stagnant water. This occurs where a river enters an ocean, sea, estuary, lake, reservoir, or (more rare ...
s and
estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environme ...
. Some species inhabit freshwater environments exclusively, while others primarily inhabit marine environments near coastal areas, and are known to venture into open ocean. Several species of sturgeon are harvested for their roe, which is processed into the luxury food caviar. This has led to serious overexploitation, which combined with other conservation threats, has brought most of the species to critically endangered status, at the edge of
extinction Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the Endling, last individual of the species, although the Functional ext ...
.


Evolution


Fossil history

Acipenseriform fishes appeared in the fossil record some 174 to 201 million years ago, during the Early Jurassic, making them some of the earliest extant
actinopterygian Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or ho ...
fishes. True sturgeons appear in the fossil record during the Upper
Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...
, with amongst the oldest known remains being a partial skull from the
Cenomanian The Cenomanian is, in the ICS' geological timescale, the oldest or earliest age of the Late Cretaceous Epoch or the lowest stage of the Upper Cretaceous Series. An age is a unit of geochronology; it is a unit of time; the stage is a unit in ...
(100-94 million years ago) of Alberta, Canada. In that time, sturgeons have undergone remarkably little morphological change, indicating their evolution has been exceptionally slow and earning them informal status as living fossils. This is explained in part by the long generation interval, tolerance for wide ranges of
temperature Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer. Thermometers are calibrated in various temperature scales that historically have relied o ...
and salinity, lack of predators due to size and bony plated armor, or scutes, and the abundance of prey items in the benthic environment. They do, however, still share several primitive characteristics, such as heterocercal tail, reduced squamation, more fin rays than supporting bony elements, and unique jaw suspension.


Phylogeny and taxonomy

Despite the existence of a
fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...
record, full classification and
phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological s ...
of the sturgeon species has been difficult to determine, in part due to the high individual and ontogenic variation, including geographical clines in certain features, such as rostrum shape, number of scutes, and body length. A further confounding factor is the peculiar ability of sturgeons to produce reproductively viable hybrids, even between species assigned to different genera. While ray-finned fishes (Actinopterygii) have a long evolutionary history culminating in the most familiar fishes, past adaptive evolutionary radiations have left only a few survivors, such as sturgeons and gars. The wide range of the acipenserids and their endangered status have made collection of systematic materials difficult. The factors have led researchers in the past to identify over 40 additional species that were rejected by later scientists. Whether the species in the ''Acipenser'' and ''Huso'' genera are monophyletic (descended from one ancestor) or
paraphyletic In taxonomy, a group is paraphyletic if it consists of the group's last common ancestor and most of its descendants, excluding a few monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In ...
(descended from many ancestors) is still unclear, though the morphologically motivated division between these two genera clearly is not supported by the genetic evidence. An effort is ongoing to resolve the taxonomic confusion using a continuing synthesis of systematic data and molecular techniques. The phylogeny of Acipenseridae, as in the cladogram, shows that they evolved from the
bony fishes Osteichthyes (), popularly referred to as the bony fish, is a diverse superclass of fish that have skeletons primarily composed of bone tissue. They can be contrasted with the Chondrichthyes, which have skeletons primarily composed of cartilage ...
. Approximate dates are from Near ''et al.'', 2012. File:Young lake sturgeon.jpg, A young lake sturgeon (''Acipenser fulvescens'') File:Hausen (Huso huso L.)editDOB.JPG, Great sturgeon or beluga (''Huso huso'') feeding on another fish File:Pallid sturgeon activity with syphoning.webmhd.webm, Pallid sturgeon (''Scaphirhynchus albus'') showing siphoning feeding behaviour File:Beluga sturgeon in aquarium.webm, thumbtime=0:01, Beluga sturgeon in an aquarium. In currently accepted taxonomy, the class Actinopterygii and the order
Acipenseriformes Acipenseriformes is an order of basal ray-finned fishes that includes living and fossil sturgeons and paddlefishes (Acipenseroidei), as well as the extinct families Chondrosteidae and Peipiaosteidae. They are the second earliest diver ...
are both
clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English ter ...
s. The family Acipenseridae is subdivided into 2 subfamilies; Acipenserinae, including the genera '' Acipenser'' and '' Huso'', and
Scaphirhynchinae Sturgeon is the common name for the 27 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 ...
, including the genera '' Scaphirhynchus'' and '' Pseudoscaphirhynchus''. However, multiple recent studies have recovered this arrangement as
paraphyletic In taxonomy, a group is paraphyletic if it consists of the group's last common ancestor and most of its descendants, excluding a few monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In ...
, instead finding '' A. oxyrhinchus'' and '' A. sturio'' to form the most basal clade among sturgeons, and all other species being in a separate clade, with the various other species of ''Acipenser'', ''Scaphirhynchus'', ''Pseudoscaphirhynchus'', and ''Huso'' to have varying levels of relationship with one another. A potential taxonomy of Acipenseridae is shown here, based on Luo ''et al''. 2019, Nedoluzhko ''et al''. 2020, and Shen ''et al.'' 2020. Note the paraphyletic relationships among genera: The exact placement of ''Scaphirhynchus'' varies depending on the study and the methods used, with some placing it within the second-most basal clade comprising primarily Pacific species (shown above), whereas others place it in its own clade that is more derived than the secondmost basal clade but less derived than the most derived Atlantic and Central Asian clade. No studies have yet delineated a relationship between it and ''Pseudoscaphirhynchus''. In addition, the exact relationships of the members of the most
derived Derive may refer to: *Derive (computer algebra system), a commercial system made by Texas Instruments * ''Dérive'' (magazine), an Austrian science magazine on urbanism *Dérive, a psychogeographical concept See also * *Derivation (disambiguation ...
, primarily Atlantic clade vary, although most analyses at least find all the species in it to form a monophyletic clade. The placement of ''A. sinensis'' also varies by the study, with some placing it as the only Pacific member of the otherwise Atlantic-based most-derived clade, whereas others place it with the rest of the Pacific sturgeons as a sister to ''A. dabryanus''.


Species

The family contains 8 extinct fossil species and 28 extant species/subspecies (include 1 species of ''Sterlet'' and 2 species of living fossils), in 4 genera. This list uses the original classification scheme: Family Acipenseridae * Genus '' Acipenser'' Linnaeus, 1758 ** †''
Acipenser albertensis ''Acipenser'' is a genus of sturgeons. With 17 living species (others are only known from fossil remains), it is the largest genus in the order Acipenseriformes. The genus is paraphyletic, containing all sturgeons that do not belong to ''Huso'', ' ...
'' Lambe 1902 > ** ''
Acipenser baerii The Siberian sturgeon (''Acipenser baerii'') is a species of sturgeon in the family Acipenseridae. It is most present in all of the major Siberian river basins that drain northward into the Kara, Laptev and East Siberian Seas, including the Ob ...
'' J. F. Brandt, 1869 ( Siberian sturgeon) *** ''
Acipenser baerii baicalensis The Siberian sturgeon (''Acipenser baerii'') is a species of sturgeon in the family Acipenseridae. It is most present in all of the major Siberian river basins that drain northward into the Kara, Laptev and East Siberian Seas, including the Ob ...
'' A. M. Nikolskii, 1896 (
Baikal sturgeon The Siberian sturgeon (''Acipenser baerii'') is a species of sturgeon in the family Acipenseridae. It is most present in all of the major Siberian river basins that drain northward into the Kara, Laptev and East Siberian Seas, including the O ...
) *** ''
Acipenser baerii stenorrhynchus ''Acipenser'' is a genus of sturgeons. With 17 living species (others are only known from fossil remains), it is the largest genus in the order Acipenseriformes. The genus is paraphyletic, containing all sturgeons that do not belong to ''Huso'', ' ...
'' A. M. Nikolskii, 1896 ** ''
Acipenser brevirostrum The shortnose sturgeon (''Acipenser brevirostrum'') 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.National Oceanic and Atmospheri ...
'' Lesueur, 1818 ( Shortnose sturgeon) ** '' Acipenser dabryanus'' A. H. A. Duméril, 1869 ( Yangtze sturgeon) ** †'' Acipenser cruciferus'' (Cope 1876) ** †''
Acipenser eruciferus ''Acipenser'' is a genus of sturgeons. With 17 living species (others are only known from fossil remains), it is the largest genus in the order Acipenseriformes. The genus is paraphyletic, containing all sturgeons that do not belong to ''Huso'', ...
'' Cope 1876 ** ''
Acipenser fulvescens The lake sturgeon (''Acipenser fulvescens''), 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 with evolutionarily basal tr ...
'' Rafinesque, 1817 ( Lake sturgeon) ** †'' Acipenser gigantissimus'' Nessov 1997 ** '' Acipenser gueldenstaedtii'' J. F. Brandt &
Ratzeburg Ratzeburg (; Low German: ''Ratzborg'') is a town in Schleswig-Holstein, Germany. It is surrounded by four lakes—the resulting isthmuses between the lakes form the access lanes to the town. Ratzeburg is the capital of the district Herzogtu ...
, 1833
( Russian sturgeon) ** ''
Acipenser medirostris The green sturgeon (''Acipenser medirostris'') is a species of sturgeon native to the northern Pacific Ocean, from China and Russia to Canada and the United States. Description Sturgeons are among the largest and most ancient of ray finn ...
'' Ayres, 1854 (
Green sturgeon The green sturgeon (''Acipenser medirostris'') is a species of sturgeon native to the northern Pacific Ocean, from China and Russia to Canada and the United States. Description Sturgeons are among the largest and most ancient of ray finn ...
) ** ''
Acipenser mikadoi The Sakhalin sturgeon (''Acipenser mikadoi'') is a species of fish in the family Acipenseridae. It is found in Japan and Russia. Environment The Sakhalin sturgeon is known to be found in either a marine or freshwater environment within demersal ...
'' Hilgendorf, 1892 (
Sakhalin sturgeon The Sakhalin sturgeon (''Acipenser mikadoi'') is a species of fish in the family Acipenseridae. It is found in Japan and Russia. Environment The Sakhalin sturgeon is known to be found in either a marine or freshwater environment within demersa ...
) ** †''
Acipenser molassicus ''Acipenser'' is a genus of sturgeons. With 17 living species (others are only known from fossil remains), it is the largest genus in the order Acipenseriformes. The genus is paraphyletic, containing all sturgeons that do not belong to ''Huso'' ...
'' Probst 1882 ** ''
Acipenser naccarii The Adriatic sturgeon (''Acipenser naccarii'') 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 Slov ...
'' Bonaparte, 1836 ( Adriatic sturgeon) ** '' Acipenser nudiventris'' Lovetsky, 1828 ( Fringebarbel sturgeon) ** †'' Acipenser ornatus'' Leidy 1873 ** '' Acipenser oxyrinchus'' Mitchill, 1815 *** '' Acipenser oxyrinchus desotoi'' Vladykov, 1955 (
Gulf sturgeon The Gulf sturgeon (''Acipenser oxyrinchus desotoi'') 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 subspeci ...
) *** '' Acipenser oxyrinchus oxyrinchus'' Mitchill, 1815 (
Atlantic sturgeon 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'', ...
) ** '' Acipenser persicus'' Borodin, 1897 (
Persian sturgeon The Persian sturgeon (''Acipenser persicus'') is a species of fish in the family Acipenseridae. It is found in the Caspian Sea and to a lesser extent the Black Sea and ascends certain rivers to spawn, mainly the Volga, Kura, Araks and Ural Rive ...
) ** '' Acipenser ruthenus'' Linnaeus, 1758 ( Sterlet) ** '' Acipenser schrenckii'' J. F. Brandt, 1869 ( Japanese sturgeon) ** ''
Acipenser sinensis The Chinese sturgeon (''Acipenser sinensis''; ) 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 be ...
'' J. E. Gray, 1835 (
Chinese sturgeon The Chinese sturgeon (''Acipenser sinensis''; ) 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 bee ...
) ** '' Acipenser stellatus'' Pallas, 1771 ( Starry sturgeon) ** '' Acipenser sturio'' Linnaeus, 1758 ( European sea sturgeon) ** †''
Acipenser toliapicus ''Acipenser'' is a genus of sturgeons. With 17 living species (others are only known from fossil remains), it is the largest genus in the order Acipenseriformes. The genus is paraphyletic, containing all sturgeons that do not belong to ''Huso' ...
'' Agassiz 1844 ex Woodward 1889 ** ''
Acipenser transmontanus White sturgeon (''Acipenser transmontanus'') is a species of sturgeon in the family Acipenseridae of the order Acipenseriformes. They are an anadromous fish species ranging in the Eastern Pacific; from the Gulf of Alaska to Monterey, California. ...
'' J. Richardson, 1836 (
White sturgeon White sturgeon (''Acipenser transmontanus'') is a species of sturgeon in the family Acipenseridae of the order Acipenseriformes. They are an anadromous fish species ranging in the Eastern Pacific; from the Gulf of Alaska to Monterey, California. ...
) ** †''
Acipenser tuberculosus ''Acipenser'' is a genus of sturgeons. With 17 living species (others are only known from fossil remains), it is the largest genus in the order Acipenseriformes. The genus is paraphyletic, containing all sturgeons that do not belong to ''Huso'', ...
'' Probst 1882 * Genus '' Huso'' J. F. Brandt &
Ratzeburg Ratzeburg (; Low German: ''Ratzborg'') is a town in Schleswig-Holstein, Germany. It is surrounded by four lakes—the resulting isthmuses between the lakes form the access lanes to the town. Ratzeburg is the capital of the district Herzogtu ...
, 1833
** '' Huso dauricus'' ( Georgi, 1775) ( kaluga) ** '' Huso huso'' ( Linnaeus, 1758) ( beluga) * Genus '' Scaphirhynchus'' Heckel, 1835 ( native to North America) ** ''
Scaphirhynchus albus The pallid sturgeon (''Scaphirhynchus albus'') is an endangered species of ray-finned fish, endemic to the waters of the Missouri and lower Mississippi river basins of the United States. It may have even reached the St. Croix River before ...
'' (
Forbes ''Forbes'' () is an American business magazine owned by Integrated Whale Media Investments and the Forbes family. Published eight times a year, it features articles on finance, industry, investing, and marketing topics. ''Forbes'' also r ...
& R. E. Richardson, 1905)
(
Pallid sturgeon The pallid sturgeon (''Scaphirhynchus albus'') is an endangered species of ray-finned fish, endemic to the waters of the Missouri and lower Mississippi river basins of the United States. It may have even reached the St. Croix River before ...
) ** ''
Scaphirhynchus platorynchus The shovelnose sturgeon (''Scaphirhynchus platorynchus'') is the smallest species of freshwater sturgeon native to North America. It is often called "hackleback", "sand sturgeon", or "switchtail". Switchtail refers to the long filament found on ...
'' ( Rafinesque, 1820) (
Shovelnose sturgeon The shovelnose sturgeon (''Scaphirhynchus platorynchus'') is the smallest species of freshwater sturgeon native to North America. It is often called "hackleback", "sand sturgeon", or "switchtail". Switchtail refers to the long filament found on ...
) ** ''
Scaphirhynchus suttkusi The Alabama sturgeon (''Scaphirhynchus suttkusi'') is a species of sturgeon native to the United States of America and now only believed to exist in of the lower Alabama River. The fish has a distinctive yellowish-orange color, grows to a si ...
''
J. D. Williams J.D. Williams (born May 22, 1978) is an American actor known for his starring roles in the HBO television programs '' Oz'' as Kenny Wangler, ''The Wire'' as Bodie Broadus and ''Pootie Tang'' as Froggy, '' Surviving Family'' (2012) as Bobby, ''T ...
& Clemmer, 1991
(
Alabama sturgeon The Alabama sturgeon (''Scaphirhynchus suttkusi'') is a species of sturgeon native to the United States of America and now only believed to exist in of the lower Alabama River. The fish has a distinctive yellowish-orange color, grows to a si ...
) * Genus '' Pseudoscaphirhynchus'' Nikolskii, 1900 ( native to Central Asia) ** ''
Pseudoscaphirhynchus fedtschenkoi The Syr Darya sturgeon (''Pseudoscaphirhynchus fedtschenkoi'') is a species of fish in the family Acipenseridae. It is found in Kazakhstan, Tajikistan and Uzbekistan, where it is endemic to the Syr Darya River and, before its drainage, the Ar ...
'' (
Kessler Kessler or Keßler (in German) may refer to: * Kessler (automobile), an American automobile made 1921–1922 * Kessler (name), people named Kessler * ''Kessler'' (TV series), a British television series from 1981 * Kessler, Ohio, an unincorporat ...
, 1872)
(
Syr Darya sturgeon The Syr Darya sturgeon (''Pseudoscaphirhynchus fedtschenkoi'') is a species of fish in the family Acipenseridae. It is found in Kazakhstan, Tajikistan and Uzbekistan, where it is endemic to the Syr Darya River and, before its drainage, the Ara ...
) ** ''
Pseudoscaphirhynchus hermanni The dwarf sturgeon, little shovelnose sturgeon, or small Amu-Darya shovelnose sturgeon (''Pseudoscaphirhynchus hermanni'') is a species of fish in the family Acipenseridae. It is found in Turkmenistan, Uzbekistan and probably in Tajikistan. P ...
'' (
Kessler Kessler or Keßler (in German) may refer to: * Kessler (automobile), an American automobile made 1921–1922 * Kessler (name), people named Kessler * ''Kessler'' (TV series), a British television series from 1981 * Kessler, Ohio, an unincorporat ...
, 1877)
(
Dwarf sturgeon The dwarf sturgeon, little shovelnose sturgeon, or small Amu-Darya shovelnose sturgeon (''Pseudoscaphirhynchus hermanni'') is a species of fish in the family Acipenseridae. It is found in Turkmenistan, Uzbekistan and probably in Tajikistan. Pop ...
) ** ''
Pseudoscaphirhynchus kaufmanni The Amu Darya sturgeon or false shovelnose sturgeon (''Pseudoscaphirhynchus kaufmanni'') is a critically endangered species of fish in the family Acipenseridae. It is found in Turkmenistan, Uzbekistan, Tajikistan and perhaps Afghanistan. It ...
'' (
Kessler Kessler or Keßler (in German) may refer to: * Kessler (automobile), an American automobile made 1921–1922 * Kessler (name), people named Kessler * ''Kessler'' (TV series), a British television series from 1981 * Kessler, Ohio, an unincorporat ...
, 1877)
(
Amu Darya sturgeon The Amu Darya sturgeon or false shovelnose sturgeon (''Pseudoscaphirhynchus kaufmanni'') is a critically endangered species of fish in the family Acipenseridae. It is found in Turkmenistan, Uzbekistan, Tajikistan and perhaps Afghanistan. It ...
)


Range and habitat

Sturgeon range from
subtropical The subtropical zones or subtropics are geographical and climate zones to the north and south of the tropics. Geographically part of the temperate zones of both hemispheres, they cover the middle latitudes from to approximately 35° north a ...
to
subarctic The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of humid continental regions and covering much of Alaska, Canada, Iceland, the north of Scandinavia, Siberia, and the Cairngorms. Genera ...
waters in
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...
and
Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelag ...
. In
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...
, they range along the Atlantic Coast from the
Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...
to
Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...
, including the
Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lakes ...
and the St. Lawrence,
Missouri Missouri is a state in the Midwestern region of the United States. Ranking 21st in land area, it is bordered by eight states (tied for the most with Tennessee): Iowa to the north, Illinois, Kentucky and Tennessee to the east, Arkansas t ...
, and
Mississippi Mississippi () is a state in the Southeastern region of the United States, bordered to the north by Tennessee; to the east by Alabama; to the south by the Gulf of Mexico; to the southwest by Louisiana; and to the northwest by Arkansas. Miss ...
Rivers, as well as along the West Coast in major rivers from
California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
and
Idaho Idaho ( ) is a U.S. state, state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Monta ...
to
British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, for ...
. They occur along the European
Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...
coast, including the
Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on ...
basin, especially in the
Adriatic Sea The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Sea) to th ...
and the rivers of
North Italy Northern Italy ( it, Italia settentrionale, it, Nord Italia, label=none, it, Alta Italia, label=none or just it, Nord, label=none) is a geographical and cultural region in the northern part of Italy. It consists of eight administrative regio ...
; in the rivers that flow into the
Black Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white ha ...
, Azov, and Caspian Seas (
Danube The Danube ( ; ) is a river that was once a long-standing frontier of the Roman Empire and today connects 10 European countries, running through their territories or being a border. Originating in Germany, the Danube flows southeast for , pa ...
,
Dnepr Dnepr may refer to: *Dnieper, a river flowing through Russia, Belarus and Ukraine to the Black Sea *Dnepr (motorcycle), a Ukraininan motocycle brand *Dnepr (rocket), a 1999 space launch vehicle *Dnepr radar, Soviet space surveillance and early warn ...
,
Volga The Volga (; russian: Во́лга, a=Ru-Волга.ogg, p=ˈvoɫɡə) is the longest river in Europe. Situated in Russia, it flows through Central Russia to Southern Russia and into the Caspian Sea. The Volga has a length of , and a catch ...
, Ural and Don); the north-flowing rivers of Russia that feed the
Arctic Ocean The Arctic Ocean is the smallest and shallowest of the world's five major oceans. It spans an area of approximately and is known as the coldest of all the oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, a ...
( Ob, Yenisei,
Lena Lena or LENA may refer to: Places * Léna Department, a department of Houet Province in Burkina Faso * Lena, Manitoba, an unincorporated community located in Killarney-Turtle Mountain municipality in Manitoba, Canada * Lena, Norway, a village in ...
, Kolyma); in the rivers of
Central Asia Central Asia, also known as Middle Asia, is a region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes the fo ...
(
Amu Darya The Amu Darya, tk, Amyderýa/ uz, Amudaryo// tg, Амударё, Amudaryo ps, , tr, Ceyhun / Amu Derya grc, Ὦξος, Ôxos (also called the Amu, Amo River and historically known by its Latin name or Greek ) is a major river in Central Asi ...
and Syr Darya) and Lake Baikal. In the Pacific Ocean, they are found in the
Amur River The Amur (russian: река́ Аму́р, ), or Heilong Jiang (, "Black Dragon River", ), is the world's tenth longest river, forming the border between the Russian Far East and Northeastern China (Inner Manchuria). The Amur proper is long ...
along the Russian- Chinese border, on
Sakhalin Sakhalin ( rus, Сахали́н, r=Sakhalín, p=səxɐˈlʲin; ja, 樺太 ''Karafuto''; zh, c=, p=Kùyèdǎo, s=库页岛, t=庫頁島; Manchu: ᠰᠠᡥᠠᠯᡳᠶᠠᠨ, ''Sahaliyan''; Orok: Бугата на̄, ''Bugata nā''; Nivkh ...
Island, and some rivers in northeast China. Throughout this extensive range, almost all species are highly threatened or vulnerable to extinction due to a combination of
habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
, overfishing, and pollution. No species is known to naturally occur south of the equator, though attempts at sturgeon
aquaculture Aquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. lot ...
are being made in
Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...
,
South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring coun ...
, and other places. Most species are at least partially anadromous, spawning in fresh water and feeding in nutrient-rich, brackish waters of
estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environme ...
or undergoing significant migrations along coastlines. However, some species have evolved purely freshwater existences, such as the lake sturgeon (''Acipenser fulvescens'') and the
Baikal sturgeon The Siberian sturgeon (''Acipenser baerii'') is a species of sturgeon in the family Acipenseridae. It is most present in all of the major Siberian river basins that drain northward into the Kara, Laptev and East Siberian Seas, including the O ...
(''A. baerii baicalensis''), or have been forced into them by human or natural
impoundment Impoundment may refer to: Water control * The result of a dam, creating a body of water ** A reservoir, formed by a dam ** Coal slurry impoundment, a specialized form of such a reservoir used for coal mining and processing * Impounded dock, an en ...
of their native rivers, as in the case of some subpopulations of
white sturgeon White sturgeon (''Acipenser transmontanus'') is a species of sturgeon in the family Acipenseridae of the order Acipenseriformes. They are an anadromous fish species ranging in the Eastern Pacific; from the Gulf of Alaska to Monterey, California. ...
(''A. transmontanus'') in the Columbia River and Siberian sturgeon (''A. baerii'') in the Ob basin.


Physical characteristics

Sturgeons retain several primitive characteristics from the bony fishes. Along with other members of the subclass Chondrostei, they are unique among bony fishes because their skeletons are almost entirely cartilaginous. To maintain structure, sturgeons are one of few organisms to retain a post-embryonic notochord that acts like a soft spine running through the body. Notably, however, the cartilagineous skeleton is not a primitive character, but a derived one; sturgeon ancestors had bony skeletons. They also lack vertebral centra, and are partially covered with five lateral rows of scutes rather than
scales Scale or scales may refer to: Mathematics * Scale (descriptive set theory), an object defined on a set of points * Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original * Scale factor, a number w ...
. They also have four barbels—sensory organs that precede their wide, toothless mouths. They navigate their riverine habitats traveling just off the bottom with their barbels dragging along gravel, or murky substrate. Sturgeon are recognizable for their elongated bodies, flattened rostra, distinctive scutes and barbels, and elongated upper tail lobes. The skeletal support for the paired fins of ray-finned fish is inside the body wall, although the ray-like structures in the webbing of the fins can be seen externally. Sturgeons are among the largest fish: some beluga (''Huso huso'') in the
Caspian Sea The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central A ...
reportedly attain over and while for kaluga (''H. dauricus'') in the
Amur River The Amur (russian: река́ Аму́р, ), or Heilong Jiang (, "Black Dragon River", ), is the world's tenth longest river, forming the border between the Russian Far East and Northeastern China (Inner Manchuria). The Amur proper is long ...
, similar lengths and over weights have been reported. They are also among the longest-lived of the fishes, some living well over 100 years and attaining sexual maturity at 20 years or more.Berg, L.S. (1962). Freshwater fishes of the U.S.S.R. and adjacent countries. volume 1, 4th edition. Israel Program for Scientific Translations Ltd., Jerusalem. (Russian version published 1948). The combination of slow growth and reproductive rates and the extremely high value placed on mature, egg-bearing females make sturgeon particularly vulnerable to
overfishing Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in t ...
. Sturgeons are
polyploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei ( eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set conta ...
; some species have four, eight, or 16 sets of chromosomes.


Life cycle

Sturgeons are long-lived, late maturing fishes. Their average lifespan is 50 to 60 years, and their first
spawn Spawn or spawning may refer to: * Spawn (biology), the eggs and sperm of aquatic animals Arts, entertainment, and media * Spawn (character), a fictional character in the comic series of the same name and in the associated franchise ** '' Spawn: A ...
does not occur until they are around 15 to 20 years old. Sturgeons are broadcast spawners, and do not spawn every year because they require specific conditions. Those requirements may or may not be met every year due to varying environmental conditions, such as the proper photoperiod in spring, clear water with shallow rock or gravel substrate, where the eggs can adhere, and proper water temperature and flow for oxygenation of the eggs. A single female may release 100,000 to 3 million eggs, but not all will be fertilized. The fertilized eggs become sticky and adhere to the bottom substrate upon contact. Eight to 15 days are needed for the embryos to mature into larval fish. During that time, they are dependent on their yolk sacs for nourishment. River currents carry the larvae downstream into backwater areas, such as
oxbows __NOTOC__ An oxbow is a U-shaped metal pole (or larger wooden frame) that fits the underside and the sides of the neck of an ox or bullock. A bow pin holds it in place. The term "oxbow" is widely used to refer to a U-shaped meander in a river ...
and sloughs, where the free-swimming fry spend their first year feeding on insect larvae and crustacea. During their first year of growth, they reach in length and migrate back into the swift-flowing currents in the
main stem In hydrology, a mainstem (or trunk) is "the primary downstream segment of a river, as contrasted to its tributaries". Water enters the mainstem from the river's drainage basin, the land area through which the mainstem and its tributaries flow. ...
river.


Behavior

Sturgeons are primarily
benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning " ...
feeders, with a diet of shellfish, crustaceans, and small fish. Exceptionally, both ''Huso'' species, the
white sturgeon White sturgeon (''Acipenser transmontanus'') is a species of sturgeon in the family Acipenseridae of the order Acipenseriformes. They are an anadromous fish species ranging in the Eastern Pacific; from the Gulf of Alaska to Monterey, California. ...
and the
pallid sturgeon The pallid sturgeon (''Scaphirhynchus albus'') is an endangered species of ray-finned fish, endemic to the waters of the Missouri and lower Mississippi river basins of the United States. It may have even reached the St. Croix River before ...
feed primarily on other fish as adults. They feed by extending their syphon-like mouths to suck food from the
benthos Benthos (), also known as benthon, is the community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone.salmon Salmon () is the common name for several commercially important species of euryhaline ray-finned fish from the family Salmonidae, which are native to tributaries of the North Atlantic (genus '' Salmo'') and North Pacific (genus '' Onco ...
. Sturgeons feed non-visually. They are believed to use a combination of sensors, including olfactory, tactile, and chemosensory cues detected by the four barbels, and electroreception using their
ampullae of Lorenzini Ampullae of Lorenzini (singular ''Ampulla'') are electroreceptors, sense organs able to detect electric fields. They form a network of mucus-filled pores in the skin of cartilaginous fish (sharks, rays, and chimaeras) and of basal actinopterygi ...
. The sturgeons' electroreceptors are located on the head and are sensitive to weak electric fields generated by other animals or geoelectric sources. The electroreceptors are thought to be used in various behaviors such as feeding, mating and migration. Many sturgeons leap completely out of the water, usually making a loud splash which can be heard half a mile away on the surface and probably further under water. Why they do this is not known, but suggested functions include group communication to maintain group cohesion, catching airborne prey, courtship display, or to help shed eggs during spawning. Other plausible explanations include escape from predators, shedding parasites, or to gulp or expel air. Another explanation is that it "simply feels good". There have been some incidents of leaping sturgeon landing in boats, and causing injuries to humans; in 2015, a 5-year-old girl was fatally injured after a sturgeon leapt from the
Suwannee River The Suwannee River (also spelled Suwanee River) is a river that runs through south Georgia southward into Florida in the southern United States. It is a wild blackwater river, about long.U.S. Geological Survey. National Hydrography Dataset h ...
and struck her.


Interactions with humans


Caviar

Globally, sturgeon fisheries are of great value, primarily as a source for caviar, but also for flesh. Several species of sturgeon are harvested for their roe which is processed into caviar—a delicacy, and the reason why caviar-producing sturgeons are among the most valuable and endangered of all wildlife resources. During the 19th century, the US was the global leader in caviar production, having cornered 90% of the world's caviar trade. Atlantic sturgeon once thrived along the east coast from Canada down to
Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and ...
. They were in such abundance in the
Hudson River The Hudson River is a river that flows from north to south primarily through eastern New York. It originates in the Adirondack Mountains of Upstate New York and flows southward through the Hudson Valley to the New York Harbor between Ne ...
that they were called "Albany beef" and sturgeon eggs were given away at local bars as an accompaniment to 5¢ beer. White sturgeon populations along the US west coast declined simultaneously under the pressure of commercial fishing and human encroachment. Within the course of a century, the once abundant sturgeon fisheries in the US and Canada had drastically declined, and in some areas had been extirpated under the pressure of commercial overharvesting, pollution, human encroachment, habitat loss, and the damming of rivers that blocked their ancestral migration to spawning grounds. By the turn of the century, commercial production of sturgeon caviar in the US and Canada had come to an end. Regulatory protections and conservation efforts were put in place by state and federal resource agencies in the US and Canada, such as the 1998 US federal moratorium that closed all commercial fishing for Atlantic sturgeon. It was during the 20th century that Russia grew to become the global leader as the largest producer and exporter of caviar. As with the decline in sturgeon populations in the US and Canada, the same occurred with sturgeon populations in the Caspian Sea. Beginning with the 1979 US embargo on Iran, poaching and smuggling sturgeon caviar was big business but an illegal and dangerous one. Officers with the
Washington Department of Fish and Wildlife The Washington Department of Fish and Wildlife (WDFW) is a department of the government of the state of Washington, United States of America. The WDFW manages over a million acres of land, the bulk of which is generally open to the public, and m ...
(WDFW) busted a poaching ring that was based in Vancouver, Washington. The poachers had harvested 1.65 tons of caviar from nearly 2,000 white sturgeon that were poached from the Columbia River. The caviar was estimated to be worth around $2 million. WDFW busted another ring in 2003, and conducted an undercover sting operation in 2006-2007 that resulted in 17 successful attempts out of a total of 19. In response to concerns over the future of sturgeons and associated commercial products, international trade for all species of sturgeons has been regulated under
CITES CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is a multilateral treaty to protect endangered plants and animals from the threats of intern ...
since 1998.


Conservation

Sturgeons are threatened by the negative impacts of overfishing, poaching,
habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
, and the construction of dams that have altered or blocked their annual migration to ancestral spawning grounds. Some species of sturgeon are extinct, and several are on the verge of extinction, including the
Chinese sturgeon The Chinese sturgeon (''Acipenser sinensis''; ) 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 bee ...
, the highly prized beluga sturgeon, and the
Alabama sturgeon The Alabama sturgeon (''Scaphirhynchus suttkusi'') is a species of sturgeon native to the United States of America and now only believed to exist in of the lower Alabama River. The fish has a distinctive yellowish-orange color, grows to a si ...
. Many species are classified as threatened or endangered, with noticeable declines in sturgeon populations as the demand for caviar increases.
IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
data indicates that over 85% of sturgeon species are at risk of extinction, making them more critically endangered than any other group of animal species. In addition to global restocking efforts, the monitoring of populations and habitat, and various other conservation efforts by national and state resource agencies as applicable to their respective countries, several conservation organizations have been formed to assist in the preservation of sturgeons around the world. On a global scale, one such organization is the World Sturgeon Conservation Society (WSCS) whose primary objectives include fostering the "conservation of sturgeon species and restoration of sturgeon stocks world-wide”, and supporting the "information exchange among all persons interested in sturgeons." The North American Sturgeon and Paddlefish Society (NASPS) and Gesellschaft zur Rettung des Störs e.V. are WSCS affiliates. WSCS has been instrumental in organizing global conferences where scientists and researchers can exchange information and address the various conservation challenges that threaten the future of sturgeons. Conservation efforts at the grass roots level are also instrumental in helping to preserve sturgeon populations, such as Sturgeon For Tomorrow which was founded in 1977, consists of volunteers and a sturgeon guarding program to monitor known spawning sites. The organization has grown exponentially over the years and has become "the largest citizen advocacy group for sturgeon in the world", and has expanded with affiliate chapters in other states that have sturgeon populations. Other projects focus on specific local issues, such as the We Pass project, seeking a solution to the migratory impasse represented by the Iron Gates in the Danube River Basin. For example, currently all anadromous
Danube The Danube ( ; ) is a river that was once a long-standing frontier of the Roman Empire and today connects 10 European countries, running through their territories or being a border. Originating in Germany, the Danube flows southeast for , pa ...
sturgeon (all species except the predominantly freshwater sterlet) are now classed as Critically Endangered or extirpated from the upper and middle reaches of the Danube River above the dams.


Other uses

Before 1800, swim bladders of sturgeon (primarily Beluga sturgeon from Russia) were used as a source of
isinglass Isinglass () is a substance obtained from the dried swim bladders of fish. It is a form of collagen used mainly for the clarification or fining of some beer and wine. It can also be cooked into a paste for specialised gluing purposes. ...
, a form of collagen used historically for the clarification of
wine Wine is an alcoholic drink typically made from Fermentation in winemaking, fermented grapes. Yeast in winemaking, Yeast consumes the sugar in the grapes and converts it to ethanol and carbon dioxide, releasing heat in the process. Different ...
and
beer Beer is one of the oldest and the most widely consumed type of alcoholic drink in the world, and the third most popular drink overall after water and tea. It is produced by the brewing and fermentation of starches, mainly derived from ce ...
, as a predecessor for gelatin, and to preserve parchments. The Jewish law of
kashrut (also or , ) is a set of dietary laws dealing with the foods that Jewish people are permitted to eat and how those foods must be prepared according to Jewish law. Food that may be consumed is deemed kosher ( in English, yi, כּשר), fr ...
, which only permits the consumption of fish with scales, forbids sturgeon, as they have ganoid scales instead of the permitted ctenoid and
cycloid scale A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scales, which can also provide effective camouflage through the use of reflection and colouration, as ...
s. While all Orthodox groups forbid the consumption of sturgeon, some conservative groups do allow it. The theological debate over its kosher status can be traced back to such 19th-century reformers as Aron Chorin, though its consumption was already common in European Jewish communities. Sturgeons were declared to be a
royal fish Under the law of the United Kingdom, whales (mammal) and sturgeons are royal fish, and when taken become the personal property of the monarch of the United Kingdom as part of his or her royal prerogative. In England and Wales According to William B ...
under a statute dating back to 1324 by King Edward II of England. Technically, the British monarchy still owns all sturgeons,
whale Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and ...
s, and
dolphin A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the b ...
s that inhabit the waters around
England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...
and
Wales Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in ...
. Under the law of the
United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and ...
, any sturgeons captured within the realm are personal property of the monarch.
William Blackstone Sir William Blackstone (10 July 1723 – 14 February 1780) was an English jurist, judge and Tory politician of the eighteenth century. He is most noted for writing the ''Commentaries on the Laws of England''. Born into a middle-class family ...
,
Commentaries on the Laws of England The ''Commentaries on the Laws of England'' are an influential 18th-century treatise on the common law of England by Sir William Blackstone, originally published by the Clarendon Press at Oxford, 1765–1770. The work is divided into four volum ...
, book I, ch. 8 "Of the King's Revenue", ss. X, p. *280
In heraldry, a sturgeon is the symbol on the coat of arms for Saint
Amalberga of Temse Amalberga of Temse (c. 741 – 10 July 772) was a Lotharingian noblewoman from the Frankish royal house of the Pippinids who is celebrated as a saint in the Roman Catholic Church and the Eastern Orthodox Church. She is especially venerated in ...
.


Notes

* This article incorporates text from a publication now in the
public domain The public domain (PD) consists of all the creative work to which no exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly waived, or may be inapplicable. Because those rights have expired ...
:


References


External links


FishBase info on Acipenser

Official website
of the World Sturgeon Conservation Society
PBS special, video clips and public outreach videos about sturgeon
{{Good article Articles containing video clips Commercial fish Apex predators Taxa named by Charles Lucien Bonaparte Extant Maastrichtian first appearances