Amu Darya sturgeon

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Amu Darya sturgeon
Live Pseudoscaphirhynchus kaufmanni.jpg
CITES Appendix II (CITES) [2]
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Acipenseriformes
Family: Acipenseridae
Genus: Pseudoscaphirhynchus
Species:
P. kaufmanni
Binomial name
Pseudoscaphirhynchus kaufmanni
Bogdanov 1874 ex. Kessler 1877
Synonyms [3] [4]
  • Scaphirhynchus hermanniKessler 1877
  • Pseudoscaphirhynchus rossikowiNikolskii 1900

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. [1] It inhabits quite shallow flowing waters that are turbid and muddy. [1] [5]

Contents

Appearance

P. kaufmanni on a 1996 stamp of Kyrgyzstan Pseudoscaphirhynchus kaufmanni 1996 stamp of Kyrgyzstan.jpg
P. kaufmanni on a 1996 stamp of Kyrgyzstan

The Amu Darya sturgeon is a small sturgeon, but the largest species of Pseudoscaphirhynchus , reaching up to 2 kg (4.4 lb) in weight and 75 cm (30 in) in total length, excluding tail filament. [5] [6] It has a long, thin tail filament. For example, two individuals that both had a length of about 55 cm (22 in) excluding tail filament were 77 cm (30.5 in) and 85.5 cm (33.5 in) including tail filament. [7] The species occurs in two morphs: a relatively large, light-coloured and late maturing morph, and a small, dark-coloured and early maturing morph. The small morph is roughly of similar size to P. hermanni , a species that lacks a tail filament. [5] [7]

Behavior

The Amu Darya sturgeon feeds on small fish and aquatic insect larvae, with large individuals being mostly piscivorous. [1] [5]

Studies in the 1960s and 1970s showed that Amu Darya sturgeon reach maturity when 5–8 years old (slightly later in females than males), but in the 1990s the youngest mature individuals only were 4 years old, possibly due to environmental changes in their habitat. [7] The breeding season is from March to May when the water is 14 to 16 °C (57 to 61 °F). [1] [5] During a season, a female of the large morph lays about 3,100–36,500 eggs and a female of the small morph about 1,000–2,000 eggs, but it is possible that they only do this every 4–5-year. [5] The species can reach an age of more than 14 years. [1] Historically, it was known to hybridize with P. hermanni, with the offspring having features that are intermediate between the two species. [5]

Conservation status

The Amu Darya sturgeon once occurred throughout the Amu Darya river basin, including its delta in the Aral Sea, today it is found in the middle Amu Darya River (between Kerki and Chardzhou (modern name is Turkmenabad) in Turkmenistan and also lower in Kyzylrabat area (Uzbekistan), also in more lower Amu Darya River (between Pitnak and Urganch in Khorezm province, Uzbekistan) and in the lower Vakhsh River (an Amu Darya tributary) in Tadjikistan. [1] It has declined because of habitat loss, pollution and poaching, and is rated as critically endangered by the IUCN. [1] Despite its threatened status, strong decline and range contraction, it can be locally fairly common and overall it is the least rare species of Pseudoscaphirhynchus ( P. fedtschenkoi is possibly extinct and P. hermanni only survives in very small numbers). [7]

In general the status of the Amu Darya sturgeon is poorly known and further surveys are necessary. [1] A part of its range is in the Amudarya State Nature Reserve. [1] Although the Amu Darya sturgeon is a fully protected species throughout its range, [8] illegal fishing is widespread and fisheries management in the region is very poor. [9] The species has been listed on CITES Appendix II since 1998. [1] This restricts international trade in the species, but two were legally exported from Uzbekistan to Russia for zoological purposes in 2002–2012, and in 2013 Uzbekistan set the export quota to twenty individuals. [9]

Many sturgeon species have been bred in captivity and this often forms the basis for restocking the wild populations. [8] In the 1980s there were attempts of doing this with the Amu Darya sturgeon. Although some progress was made, captive breeding ultimately failed because the embryos died. [9] Since 2010, Eurasian Regional Association  of Zoos and Aquariums (EARAZA) together with various Russian and Uzbekistan institutes as well as officials of Tajikistan) has attempted to start a breeding program for the Amu Darya sturgeon, but as of 2021 it has not succeeded (in 2020  Khorezm Mamun Academy in Khiva (Khorezm province branch of Academy of Sciences of Uzbekistan) - the main partner in the program) has temporary stopped shovelnose conservation project because of lack of financial support) although some progress was made (the eggs were incubated in the field in 2012 but the embryos died). [8]

Taxonomy

The karyotype of the Amu Darya sturgeon consists of roughly 118–120 chromosomes; it is classified as a low-chromosome group acipenserid fish. Studies of its genetics and karyotype show clear differences compared to the shovelnose sturgeon (Scaphirhynchus platorhynchus), indicating that the usually recognized subfamily Scaphirhynchinae is polyphyletic. [10] Further karyological research on the Amu Darya sturgeon may help in determining polyploid evolution in acipenserid fish.[ citation needed ]

Related Research Articles

Amu Darya River in Central Asia and Afghanistan

The Amu Darya is a major river in Central Asia and Afghanistan. Rising in the Pamir Mountains, north of the Hindu Kush, the Amu Darya is formed by the confluence of the Vakhsh and Panj rivers, in the Tigrovaya Balka Nature Reserve on the border between Afghanistan and Tajikistan, and flows from there north-westwards into the southern remnants of the Aral Sea. In its upper course, the river forms part of Afghanistan's northern border with Tajikistan, Uzbekistan, and Turkmenistan. In ancient history, the river was regarded as the boundary of Greater Iran with "Turan", which roughly corresponded to present-day Central Asia.

Kyzylkum Desert Desert in Central Asia between the Amu Darya and Syr Darya

The Kyzylkum Desert is the 15th largest desert in the world. Its name means Red Sand in Turkic languages. It is located in Central Asia, in the land between the confluent rivers Amu Darya and Syr Darya, a region historically known as Transoxania. Today it is divided between Kazakhstan, Turkmenistan and Uzbekistan. It covers about 298,000 km2 (115,000 sq mi).

Sturgeon Ray-finned fish

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 Jurassic epoch, some 174 to 201 million years ago. 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. Two closely related species, Polyodon spathula and Psephurus gladius are of the same order, Acipenseriformes, but are in the family Polyodontidae and are not considered to be "true" sturgeons. Both sturgeons and paddlefish have been referred to as "primitive fishes" because their morphological characteristics have remained relatively unchanged since the earliest fossil record. Sturgeons are native to subtropical, temperate and sub-Arctic rivers, lakes and coastlines of Eurasia and North America.

Acipenseriformes Order of fishes

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, and the more basal Eochondrosteus.

Karakalpakstan Sovereign republic of Uzbekistan

Karakalpakstan, officially the Republic of Karakalpakstan, is an autonomous republic within Uzbekistan. It occupies the whole northwestern part of Uzbekistan. The capital is Nukus. The Republic of Karakalpakstan has an area of 166,590 km2 (64,320 sq mi). Its territory covers the classical land of Khwarezm, which in classical Persian literature was known as کات.

Türkmenabat Capital of Lebap Province, Turkmenistan

Türkmenabat, formerly and since medieval times Chardzhou, and in ancient times Āmul, is the second-largest city in Turkmenistan and the capital of Lebap Province. As of 2009, it had a population of approximately 254,000 people. From 1924 to 1927 it was briefly renamed Leninsk in honor of Vladimir Lenin.

Xorazm Region Region in Uzbekistan

Xorazm Region or Khorezm Region as it is still more commonly known, is a viloyat (region) of Uzbekistan located in the northwest of the country in the lower reaches of the Amu Darya River. It borders with Turkmenistan, Karakalpakstan, and Bukhara Region. It covers an area of 6,050 square kilometres (2,340 sq mi). The population is estimated 1,893,300 (2021), with 67% living in rural areas. The capital is Urgench. Other major towns include Xonqa, Khiva, Shovot, and Pitnak.

European sea sturgeon Species of fish

The European sea sturgeon, also known as the Atlantic sturgeon or common sturgeon, is a species of sturgeon endemic to France. It was formerly abundant, being found in coastal habitats all over Europe. 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.

Shovelnose sturgeon Species of fish

The shovelnose sturgeon 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 the upper lobe of the caudal fin. Shovelnose sturgeon are the most abundant sturgeon, found in the Missouri River and Mississippi River systems, and the only commercially fished sturgeon in the United States of America.

Pallid sturgeon Species of fish

The pallid sturgeon is an endangered species of ray-finned fish, endemic to the waters of the Missouri and lower Mississippi river basins of the United States.

Syr Darya sturgeon Species of fish

The Syr Darya sturgeon 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 Aral Sea. Due to the loss of its breeding site and damming projects over the length of the river, it is currently considered Critically Endangered and likely extinct, as no sightings have been reported since 1960. The sturgeon is among the 25 "most wanted lost" species that are the focus of Global Wildlife Conservation's "Search for Lost Species" initiative.

<i>Pseudoscaphirhynchus</i> Genus of fishes

Pseudoscaphirhynchus is a genus of relatively small, highly threatened sturgeons that are restricted to the Aral Sea system, including the Amu Darya and Syr Darya river basins, in Central Asia.

Dwarf sturgeon Species of fish

The dwarf sturgeon, little shovelnose sturgeon, or small Amu-Darya shovelnose sturgeon is a species of fish in the family Acipenseridae. It is found in Turkmenistan, Uzbekistan and probably in Tajikistan.

<i>Huso</i> Genus of fishes

Huso is a genus of large sturgeons from Eurasia. It contains two species, which both are critically endangered:

<i>Scaphirhynchus</i> Genus of fishes

Scaphirhynchus is a genus of sturgeons native to the United States of America. All species in this genus are considered to be threatened. The pallid sturgeon is Endangered and the Alabama sturgeon is Critically Endangered.

Scaphirhynchinae Subfamily of fishes

Scaphirhynchinae is a subfamily of sturgeon which includes two genera comprising a total of six species.

Gurlan is a town and seat of Gurlan District in Xorazm Region in Uzbekistan. It is located near the border with Turkmenistan in western Uzbekistan, 42 kilometres (26 mi) north-west of Urgench, north of Shovot, and south of the Amu Darya river. Gurlen is a major centre for cotton production, and rice and yams are also significant other crops.

Fishing industry in Turkmenistan

The fishing industry in Turkmenistan has been of benefit to the economy of Turkmenistan and food supply, particularly on the Caspian Sea for centuries. The fishing industry took off around 1910 in Turkmenistan but declined between 1950 and 1990, with the banning of sturgeon catching in Turkmen waters. Today, the fishing industry is developing rapidly, due to technological modernization and renewal schemes and the growth of aquaculture. Under the command of the Turkmen president, fishing facilities in the country have been reconstructed and constructed with modern industry infrastructure, particularly in the Caspian Sea 610 km coastline of western Turkmenistan in Balkan Province.

Aral-Paygambar, which means the island of the prophet, is an island on the Amu Darya river which separates Uzbekistan and Afghanistan. The nature reserve was created in 1960 on the island of Aral-Paygambar on the Amu Darya river near Termez. The island has 3.1 hectares for conservation of riparian forests and the unique population of Bukhara deer. In all there are 150 species of plants, 21 species of mammals, 143 species of birds, 25 species of reptiles, and c. 35 species of fish. Many rare and endangered species, including large and small Amu Darya shovelnose, golden eagles, black storks, jungle cat, dressing, Asian otters, etc. In recent years, due to the reduction of floods and expansion households. activity in the floodplain degradation the national complex.

Khorezm fortresses

The Khorezm Fortresses, or Elliq Qala in Uzbek, are a collection of more than 50 desert fortresses in Karakalpakstan and the Khorezm Region of Uzbekistan. They are included on UNESCO’s Tentative List for World Heritage Site status as the Desert Castles of Ancient Khorezm.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 Mugue, N. (2010). "Pseudoscaphirhynchus kaufmanni". IUCN Red List of Threatened Species . 2010: e.T18601A8498207. doi: 10.2305/IUCN.UK.2010-1.RLTS.T18601A8498207.en . Retrieved 17 November 2021.
  2. "Appendices | CITES". cites.org. Retrieved 14 January 2022.
  3. Froese, R.; Pauly, D. (2017). "Acipenseridae". FishBase version (02/2017). Retrieved 18 May 2017.
  4. "Acipenseridae" (PDF). Deeplyfish – fishes of the world. Retrieved 18 May 2017.
  5. 1 2 3 4 5 6 7 Birstein, V.J.; J.R. Waldman; and W.E. Bemis, editors (1997). Sturgeon biodiversity and conservation, pp. 377–378, 381–382. Kluwer Academic Publishing. ISBN   0-792-34517-7
  6. Froese, Rainer; Pauly, Daniel (eds.) (2019). "Pseudoscaphirhynchus kaufmanni" in FishBase . May 2019 version.
  7. 1 2 3 4 Salnikov, V.B.; V.J. Birstein; and R.L. Mayden (1996). The contemporary status of the two Amu Darya River shovelnose sturgeons, Pseudoscaphirhynchus kaufmanni and P. hermanni. The Sturgeon Quarterly 4(3): 10–14.
  8. 1 2 3 Mikodina, E.; and A. Novosadova (2015). Rare Acipenserids in Russian Aquaculture. ВОПРОСЫ РЫБНОГО ХОЗЯЙСТВА БЕЛАРУСИ 31: 38–51.
  9. 1 2 3 UNEP-WCMC. (2013). Review of species selected on the basis of new or increased CITES export quotas in 2013: Pseudoscaphirhynchus kaufmanni from Uzbekistan & update to the 2013 quota analysis UNEP-WCMC, Cambridge.
  10. Kovalev, Konstantin; Balashov, Dmitry; Cherniak, Alexey; Lebedeva, Elena; Vasil’eva, Ekaterina; Vasil’ev, Victor (30 June 2014). "The karyotype of the Amu Darya sturgeon, Pseudoscaphirhynchus kaufmanni (Actinopterygii: Acipenseriformes: Acipenseridae)". Acta Ichthyologica et Piscatoria. 44 (2): 111–116. doi: 10.3750/AIP2014.44.2.04 .