EFFECTS ON WILDLIFE OF AT-PLANTING CORN APPLICATIONS OF GRANULAR CARBOFURAN

Application, at planting, of a granular formulation of the insecticide carbofuran to 195 ha of corn resulted in wildlife mortalities in Frederick County, Maryland [USA], in April and May 1980. Systematic field searches within 96 h of treatment revealed 6 dead songbirds (order Passeriformes), 5 of which contained residues of carbofuran ranging from 1.6-17.0 ppm (gastrointestinal tract and liver combined). As American robin (Turdus migratorius) and a mallard (Anas platyrhychos) were observed exhibiting symptoms consistent with cabofuran posioning. A dead white-footed mouse (Peromyscus leucopus) found 24-h posttreatment contained 15.1 ppm carbofuran. The pesticide was detected in 10 of 12 common grackles (Quiscalus quiscula) shot at the site (gastrointestinal tract and liver: .hivin.x = 0.75 ppm, SE = 0.19), suggesting extensive sublethal exposure among birds feeding in treated fields. Captive house sparrows (Passer domesticus) and red-winged blackbirds (Agelaius phoeniceus) were orally administered carbofuran granules; does as low as 1 granule resulted in fatalities with both species. Given the extensive annual use of granular carbofuran (> 4 .times. 106 ha) in the USA, numerous wildlife mortalities are likely.