Avian food selection with application to pesticide risk assessment: are dead and desiccated insects a desirable food source?
Past evaluations of pesticide exposure have been conducted with substantial uncertainty regarding avian consumption of contaminated food items. One question is whether birds consume invertebrates that are killed by a chemical application and that may present an increasing chemical concentration as they desiccate. We addressed the research question in two phases. First, a laboratory study was conducted in which wild-caught birds were individually offered three food choices, i.e., live, fresh-dead, and desiccated insect larvae. Second, these same food choices plus live, fresh-dead, and desiccated crickets were presented in study plots in two agricultural crops, i.e., a cornfield and an orchard. The experimental food items were monitored with videography equipment to determine their fate and to compare laboratory and field results. Laboratory results showed that birds have a strong preference for live and fresh-dead prey over desiccated prey, with live prey taken before fresh-dead prey in most trials. The field study revealed a similar preference for live prey over desiccated prey, with preference for fresh-dead prey intermediate to the two other types.
Stafford
Jennifer M
JM
Springborn Smithers Laboratories, Avian Toxicology Division, Carolina Research Center, PO. Box 620, 2900 Quakenbush Road, Snow Camp, North Carolina 27349, USA. jstafford@springbornsmithers.com
Brewer
Larry W
LW
Gessaman
James A
JA
D000818:Animals; D000835:Animals, Wild; D001717:Birds / Q000502:physiology*; D003627:Data Interpretation, Statistical; D004781:Environmental Exposure / Q000032:analysis*; D020387:Food Chain; D005506:Food Contamination / Q000032:analysis*; D005518:Food Preferences; D007313:Insecta; D007814:Larva; D010573:Pesticide Residues / Q000032:analysis / Q000633:toxicity*; D018570:Risk Assessment
D010573:Pesticide Residues