Danube an important industry. The Upper Danube ecoregion alone has about 60 fish species and the Lower Danube–Dniester ecoregion has about twice as many. Among these are an exceptionally high diversity of sturgeon, a total of six species (beluga, Russian sturgeon, bastard sturgeon, sterlet, starry sturgeon and European sea sturgeon), but these are all threatened and have largely–or entirely in the case of the European sea sturgeon–disappeared from the river. The huchen, one of the largest species of salmon, is endemic to the Danube basin, but has been introduced elsewhere by humans. Important tourist and natural spots along the Danube include
Crab meat and the animal is then returned to the water. The practice is defended because some crabs can naturally autotomise (shed) limbs and then about a year later after a series of moults, regenerate these limbs. In Western Europe crab meat is derived primarily from the species "Cancer pagurus". "C. pagurus" is a large crab noted for the sweet, delicate flavour of its meat. It is also known as the "Brown Crab", the "Common Crab" or the "Edible Crab". The United Kingdom is the largest fishery for "C. pagurus" with large fisheries in Scotland and a smaller but substantial fishery in