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
What Bird is That? Edition What Bird is That?" was published by Australia's Heritage Publishing in 2011, the latest release of Cayley’s “big bird book” complete with Lindsey’s revisions. It is 832 pages, features 769 birds and includes all 460 of Cayley’s full-colour paintings, many showing groups of related birds. New to this edition was an accompanying e-book "What Bird Call is That?", which identifies and illustrates 101 birds from "What Bird is That?", as well as providing sound files of each featured bird’s distinctive call. The sound files were provided by David Stewart. "What Bird is That?" plays a central role in Australian