Assessment of pesticide residues in army cutworm moths (Euxoa auxiliaris) from the Greater Yellowstone Ecosystem and their potential consequences to foraging grizzly bears (Ursus arctos horribilis)

摘要: During summer, a grizzly bear (Ursus arctos horribilis) in the Greater Yellowstone Ecosystem (GYE) (USA) can excavate and consume millions of army cutworm moths (Euxoa auxiliaris) (ACMs) that aggregate high elevation talus. Grizzly bears GYE were listed as threatened by US Fish Wildlife Service 1975 proposed for delisting 2005. However, questions remain about key foods. For example, ACMs are agricultural pests concern exists whether they contain pesticides could be toxic to bears. Consequently, we investigated transport foraging sites and, if so, these levels In 1999 collected analyzed from six sites. screened 32 with gas chromatography electron capture detection (GC–ECD). Because tandem mass spectrometry (GC–MS/MS) more sensitive than GC–ECD certain pesticides, revisited one site 2001 GC–MS/MS. contained trace or undetectable 2001, respectively. Based on chemical numbers consume, calculated potential chemicals reach physiological toxicity. These calculations indicate do not physiologically allay concerns at risk transported ACMs. If control changes future, screening new ACM samples taken may warranted. � 2006 Elsevier Ltd. All rights reserved.