Sturgeon

Distribution: Northern Hemisphere Maturity: Male – 11 to 12 years, Female – 18 to 20 years Life expectancy: Up to 60 years Diet: Carnivorous Number of eggs: Up to two and a half million eggs IUCN red list status: 17 of the 25 species are Critically Endangered The sturgeon (Acipenseridae) is a family of fish comprising four genera and 25 species. Native to the northern hemisphere, most sturgeon species remain in freshwater throughout their lives, although some are anadromous, meaning they typically live in freshwater but may migrate to the ocean. Fossil records show that this family has changed very little over millions of years, suggesting it is part of an ancient group of animals. Although most sturgeons live for around 60 years, some individuals have been documented to surpass 120 years. Sturgeons are characterized by four barbels located in front of the mouth, a heterocercal tail with a larger upper lobe, and bony plate-like structures instead of scales. This group of fish is critically endangered because of overfishing. Their long lifecycle and late maturity mean that too many individuals are removed from the population before reaching reproductive age, leading to low numbers of breeding adults.