The Eurasian beaver (Castor fiber) or European beaver is a beaver species that was once widespread in Eurasia, but was hunted to near-extinction for both its fur and castoreum. At the turn of the 20th century, only about 1,200 beavers survived in eight relict populations in Europe and Asia. It has been reintroduced to much of its former range, and now occurs from Spain, Central Europe, Great Britain and Scandinavia to a few regions in China and Mongolia. It is listed as least concern on the IUCN Red List, as it recovered well in most of Europe. It is extirpated in Portugal, Moldova, and Turkey. Taxonomy Castor fiber was the scientific name used by Carl Linnaeus in 1758, who described the beaver in his work Systema Naturae. Between 1792 and 1997, several Eurasian beaver zoological specimens were described and proposed as subspecies, including: C. f. albus and C. f. solitarius by Robert Kerr in 1792 C. f. fulvus and C. f. variegatus by Johann Matthäus Bechstein in 1801 C. f. galliae by Étienne Geoffroy Saint-Hilaire in 1803 C. f. flavus, C. f. varius and C. f. niger by Anselme Gaëtan Desmarest in 1822 C. f. gallicus Johann Baptist Fischer in 1829 C. f. proprius by Gustaf Johan Billberg in 1833 C. f. albicus, C. f. balticus and C. f. vistulanus by Paul Matschie in 1907 C. f. birulai and C. f. pohlei by Serebrennikov in 1929 C. f. tuvinicus by Lavrov in 1969 C. f. belarusicus and C. f. osteuropaeus by Lavrov in 1974 C. f. belorussicus and C. f. orientoeuropaeus by Lavrov in 1981 C. f. bielorussieus by Lavrov in 1983 C. f. introductus by Saveljev in 1997 These descriptions were largely based on very small differences in fur colour and cranial morphology, none of which warrant a subspecific distinction. In 2005, analysis of mitochondrial DNA of Eurasian beaver samples showed that only two evolutionarily significant units exist: a western phylogroup in Western and Central Europe, and an eastern phylogroup in the region east of the Oder and Vistula rivers. The eastern phylogroup is genetically more diverse, but still at a degree below thresholds considered sufficient for subspecific differentiation. Description The Eurasian beaver's fur colour varies between regions. Light, chestnut-rust is the dominant colour in Belarus. In Russia's Sozh River basin, it is predominantly blackish brown, while in the Voronezh Reserve beavers are both brown and blackish-brown. The Eurasian