Soil-Food-Chain-Pesticide Wildlife Relationships in Aldrin-Treated Fields

Abstract

Soil-food-chain-pesticide wildlife relationships were investigated to learn the concentration of pesticide residues present in soils, macro-invertebrates, vertebrates, and seeds as a result of annual ap- plications of aldrin at recommended rates for pest control. Two central Missouri cornfields treated with aldrin at 1 lb/acre, for 16 and 15 of the past 17 years, were selected for study during 196S67. Primary samples collected for residue analyses included soils, earthworms ( Lumbricidae ), crickets ( Gryllidae ), and two kinds of ground beetles (Carabidae) obtained during early April, June, August, and October. Vertebrates and plant seeds collected during 1967 included white-footed mice (Peromyscus manicu- latus ), toads ( Bufo americanus ), snakes ( Thamnophis sirtalis and Pituophis sayi ), corn ( Zes Mays ) a foxtail (Setaria Faberii), and annual sunflower (Helianthus annuos). Pesticide residues consisted pri- marily of dieldrin, the degradation product of aldrin. Combined aldrin and dieldrin residues, as two- field all-season averages, wet weight basis, were: soils, 0.31 ppm; earthworms, 1.49 ppm; crickets, 0.23 ppm; Harpalus ground beetles, 1.10 ppm; Poecilus ground beetles, 9.67 ppm, white-footed mice, 0.98 ppm; toads, 3.53 ppm; garter snakes, 12.3S ppm; and corn, foxtail, and sunflower seeds less than 0.02 ppm each. Unusually high average residues (37.48 ppm) in Poecilus beetles during June, 1967, were attributed to abnormally high soil moisture and predacious feeding habits of these insects. SOIL-FOOD-CHAIN-PESTICIDE WILDLIFE RELATIONSHIPS IN ALDRIN-TREATED FIELDS1 Abstract: Soil-food-chain-pesticide wildlife relationships were investigated to learn the concentration of pesticide residues present in soils, macro-invertebrates, vertebrates, and seeds as a result of annual ap- plications of aldrin at recommended rates for pest control. Two central Missouri cornfields treated with aldrin at 1 lb/acre, for 16 and 15 of the past 17 years, were selected for study during 196S67. Primary samples collected for residue analyses included soils, earthworms ( Lumbricidae ), crickets ( Gryllidae ), and two kinds of ground beetles (Carabidae) obtained during early April, June, August, and October. Vertebrates and plant seeds collected during 1967 included white-footed mice (Peromyscus manicu- latus ), toads ( Bufo americanus ), snakes ( Thamnophis sirtalis and Pituophis sayi ), corn ( Zes Mays ) a foxtail (Setaria Faberii), and annual sunflower (Helianthus annuos). Pesticide residues consisted pri- marily of dieldrin, the degradation product of aldrin. Combined aldrin and dieldrin residues, as two- field all-season averages, wet weight basis, were: soils, 0.31 ppm; earthworms, 1.49 ppm; crickets, 0.23 ppm; Harpalus ground beetles, 1.10 ppm; Poecilus ground beetles, 9.67 ppm, white-footed mice, 0.98 ppm; toads, 3.53 ppm; garter snakes, 12.3S ppm; and corn, foxtail, and sunflower seeds less than 0.02 ppm each. Unusually high average residues (37.48 ppm) in Poecilus beetles during June, 1967, were attributed to abnormally high soil moisture and predacious feeding habits of these insects.