Danube bleak by the building of dams across many of the rivers. Landlocked populations survive in small rivers and reservoirs, breeding in the small streams above the dams. The main Caspian Sea population has found ways of spawning below the dams. Overfishing and pollution in the Caspian Sea could impact on the Danube bleak but in 2008 the IUCN Red List of Threatened Species listed it as being of "Least concern". The Danube bleak feeds on small crustaceans, worms, molluscs, insect larvae, insects and small fish. Male Danube bleaks assemble in May to July at spawning sites in fast flowing streams with
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 .