Pollution and Pesticides

Pollution and pesticides remain significant stressors on some bird populations. Pollutants from agriculture, logging activities, urban uses, and other human activities can significantly degrade watershed habitats. Water quality regulations have been effective at controlling point sources of pollution. But, non-point source pollution from overland runoff and air deposition is still a significant contributor to the degradation of soil and water. Use of pesticides and other toxins can also directly and indirectly affect bird species.

For example:

• In 1992, Dr. David Pimentel and his colleagues at Cornell University estimated that bird losses due to pesticide use cost the U.S., conservatively, over $2 billion per year based on losses to hunting and other revenues.

• Other studies have reported that Canada Geese, duck species, and Brant have been killed by parathion and methyl parathion, carbofuran, and diazinon. The EPA has estimated that carbofuran alone kills 1 to 2 million birds each year in the United States. Worldwide, it is estimated that up to 67 million birds are killed each year by pesticides.

• Selenium pollution in agricultural drain water was found at Kesterson National Wildlife Refuge to cause deformities and death in exposed birds.

See the American Bird Conservancy site for more information on the effects of pollutants and pesticides on birds.