In the time that records have been kept of bird populations, 20 percent of all species have gone extinct. More are likely to follow. In March the release of a large-scale, 24-year survey [pdf] gave one of the clearest pictures yet of the decline of Australian and Asian shorebirds, including the long-distance migrants that are most difficult to monitor. The results of the survey are dire.
Every October for more than two decades, teams from the University of New South Wales in Australia counted birds from an airplane flown low over 130,000 square miles of wetlands in the eastern third of the continent. Their counts showed a steady decline, beginning in the mid-1980s. By 2006 the number of migratory shorebirds had dropped by 73 percent and the number of Australia’s resident shorebirds had fallen by 81 percent. “The extent of the decline took us by surprise,” says evolutionary ecologist Silke ...
