Bird migration perils cold temperatures on the wintering grounds kills thousands of birds, resulting in 30-90% population declines of migratory birds. For example, between 27000 and 62000 ducks, mostly tufted duck and common pochard, starved to death during a very cold winter in March 1986. The passing of Migratory Bird Treaty (US, 1916) and Migratory Birds Convention Act (Canada, 1917) made it illegal to kill or capture migratory birds. Even though migratory bird acts were passed at the beginning of the 19th century, many countries still have no laws or programs to protect migratory birds. International bird trade is a multibillion-dollar industry and
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