Bird Populations Are Under Siege Worldwide
Notes:
Threatened Birds as a Percentage of Total Known Avian Species
Approximately 11 percent of all known bird species are threatened with extinction. Habitat fragmentation or loss is the principal factor in this decline, but harvesting for food and trade and competition from nonnative species are important as well.
Source: Biodiversity Data Table "Globally Threatened Species: Mammals, Birds, and Higher Plants, 1990s", available in PDF format through http://www.wri.org/facts/data-tables.html.