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
Common minke whale Common minke whale The common minke whale or northern minke whale ("Balaenoptera acutorostrata") is a species of minke whale within the suborder of baleen whales. It is the smallest member of the rorquals and the second smallest species of baleen whale. Although first ignored by whalers due to its small size and low oil yield, it began to be exploited by various countries beginning in the early 20th century. As other species declined larger numbers of common minke whales were caught, largely for their meat. It is now one of the primary targets of the whaling industry. There is a