The importance of pesticide exposure duration and mode on the foraging of an agricultural pest predator.

Abstract

The striped lynx spider (Oxyopes salticus), is a natural predator of crop pests and therefore frequently encounters pesticides on its substrate and its prey. While pesticide exposure may negatively impact the lifespan of spiders, sublethal effects can also alter their normal behaviors. This study examined how prey capture was affected when spiders and their prey were exposed to bifenthrin and malathion. When spiders were continually exposed to bifenthrin residues, prey capture decreased over time, but mortality was not affected. Malathion exposed spiders, however, showed increased mortality, but their ability to catch prey was unaltered. When spiders encountered pesticide dosed prey, predation was unaffected, implying that spiders are unable to detect residues on prey. These results improve the understanding of how pesticides affect natural pest control and raise questions about the functional roles that spiders play when exposed to different chemicals.