Organochlorine pesticide contaminants detrimentally affect wildlife in many ways, including lowered reproductive success, endocrine disruption, and embryonic defects. Most organochlorine pesticides have been banned in the United States after the recognition of these effects. However, these pesticides are still used in Central and South America, and little information is available concerning the levels of pesticide contamination in wildlife from these areas. Furthermore, little data exist regarding organochlorine pesticide contamination in passerines (songbirds). The purpose of this study was to determine the presence in passerines of organochlorine pesticides that are of concern to the Environmental Protection Agency. Neotropical resident species (i.e. those living year-round Central and South America) were collected from Argentina and Peru in 1996, Neotropical migrant species (i.e. those that winter in Central and South America and breed in North America) were collected in central and western Illinois from 1991-1996, and Nearctic resident species (i.e. those living year-round in North America) were collected in central Illinois in 1995 and 1996. Contamination levels were compared between each of the above geographic locations. Predominate pesticides found in Nearctic resident and Neotropical migrant species included DDE, dieldrin and heptachlor epoxide. No significant levels of organochlorine pesticides were found in the Neotropical resident birds. Significantly higher pesticide levels were found in Neotropical migrants than in Neotropical residents. No difference was found in pesticide levels among the Neotropical migrants in relation to age class. These findings suggest that passerines may be acquiring organochlorine pesticides in North America.
Sager '97, Tyler A., "Organochlorine Pesticide Contamination in New World Passerines" (1997). Honors Projects. 10.