Beluga Sturgeon
The beluga or European sturgeon (Huso huso) is a species of anadromous fish in the sturgeon family (Acipenseridae) oforder 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 roe—known as beluga caviar— 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 most similar to the Huso huso beluga is the Huso dauricus kaluga, also referred to as the "river beluga". The largest generally accepted record is of a female taken in 1827 in the Volga estuary at 1,571 kg (3,460 lb) and 7.2 m (24 ft). Several other records of aged sturgeon exceed 5 m (16 ft). These great sizes mark the beluga as the largest freshwater fish in the world, and as a rival in size to the ocean sunfish among all extant bony fishes. The giant belugas are much larger than the Mekong giant catfish or the arapaima. 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 always 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 142–328 cm (4.66–10.76 ft) long and weigh 19–264 kg (42–580 lb). The female beluga is typically 20% larger than the male.
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