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
Red king crab Red king crab The red king crab, Paralithodes camtschaticus, also called Kamchatka crab or Alaskan king crab, is a species of king crab native to the Bering Sea. It grows to a leg span of , and is heavily targeted by fisheries. The red king crab is the largest species of king crab. Red king crabs can reach a carapace width of up to , a leg span of , and a weight of . Males grow larger than females. Today red king crabs infrequently surpass in carapace width and the average male landed in the Bering Sea weighs .