Ability of Orconectus rusticus to Recover from Exposure to the Pesticide Imidacloprid

Abstract

Imidacloprid, the most widely used pesticide in the world, is known to affect invertebrates’ ability to move and feed. There is growing concern about the effects Imidacloprid may be having on non-target organisms. In my study I asked the question can organisms exposed to Imidacloprid recover mobility. I exposed crayfish to either 1 µg•L-1, 10 µg•L-1 or 100 µg•L-1 of Imidacloprid for seven days. After the week of exposure, crayfish were transferred to pesticide-free water and tested their mobility by timing how long it took each individual crayfish to right itself after being placed onto its back. This test was repeated every three days for a total of five cycles. The crayfish exposed to either 1 µg•L-1 or 10 µg•L-1 of Imidacloprid did not show differences in average flip times compared to the control crayfish at any point during the study. Crayfish exposed to 100 µg•L-1 of exhibited significantly different flip times from the 1 µg•L-1, 10 µg•L-1 and control crayfish until the thirteenth day. At that time, they were not significantly different from the 10 µg•L-1 exposed crayfish. The righting time of crayfish exposed to 100 µg•L-1 trended towards the control over the course of the recovery period.