The beluga or European sturgeon (Huso huso) is a species of anadromous fish in the sturgeon family (Acipenseridae) of order Acipenseriformes. It is found primarily in the Caspian and Black Sea basins, and occasionally in the Adriatic Sea. Heavily fished for the female's valuable roeâ"known as beluga caviarâ"the beluga is a huge and late-maturing fish that can live for 118 years. The species' numbers have been greatly reduced by overfishing and poaching, prompting many governments to enact restrictions on its trade.
The common name for the sturgeon, as for the unrelated beluga whale, is derived from the Russian word белÑй (belyy), meaning "white".
Behavior
The beluga is a large predator which feeds mostly on fish, also rarely consuming waterfowl and seal pups.
Like most sturgeons, the beluga is anadromous, migrating upstream in rivers to spawn.
Size
The largest accepted record is of a female taken in 1827 in the Volga estuary at 1,571Â kg (3,463Â lb) and 7.2Â m (23.6Â ft). Several other records of aged sturgeon exceed 5Â m (16.4Â ft). These great sizes mark the beluga as the largest freshwater fish in the world. A few other species of sturgeon can attain great sizes but none match the maximum sizes known for the beluga, like Chinese, Pacific White, Oceanic European, Atlantic, Baikalian, and Kaluga, the latter a close cousin which can attain a maximum weight of 1,000Â kg (2,200Â lb), thus attaining the second largest sturgeon size. It may be considered as a rival in size to the ocean sunfish among all extant bony fishes although that marine, passive giant has not been nearly as heavily fished nor takes as long to attain great sizes as does the beluga so more regularly attain massive weights. The Beluga also rivals the great white shark, the Greenland shark, and the tiger shark for the title of largest actively predatory fish, only the great white easily exceeding the beluga's maximum size. The giant belugas are much larger than the Mekong giant catfish, the arapaima or other sizable rivals for the title of largest freshwater fish. Nevertheless, some scientists still consider the Mekong giant catfish to be the largest true freshwater fish, owing to sturgeons' ability to survive in seawater and that it spends much of its life in brackish environments.
Beluga of such great sizes are very old (continuing to grow throughout life) and have become increasingly rare in recent decades due to the heavy fishing of this species. Today, belugas that are caught are generally 142â"328Â cm (4.66â"10.76Â ft) long and weigh 19â"264Â kg (42â"582Â lb). The female beluga is typically 20% larger than the male.
Uses
Beluga caviar is considered a delicacy worldwide. The flesh of the beluga, though, is not particularly renowned but is a hearty white meat similar to that of swordfish. Beluga caviar has long been scarce and expensive and its endangered status has made its caviar more expensive in worldwide markets outside of the United States.
Its air bladder is said to make the best isinglass.
Status
IUCN classifies the beluga as critically endangered. It is a protected species listed in appendix III of the Bern Convention, and its trade is restricted under CITES appendix II. The Mediterranean population is strongly protected under appendix II of the Bern Convention, prohibiting any intentional killing of these fish.
The United States Fish and Wildlife Service has banned imports of beluga caviar and other beluga products from the Caspian Sea since October 6, 2005, after listing beluga sturgeon under the U.S. Endangered Species Act.
References
External links
- "Huso huso". Integrated Taxonomic Information System. Retrieved 24 January 2006.Â
- Annex II of the Convention on the Conservation of European Wildlife and Naturaabitats. Revised 1 March 2002.