The Crayfish Crisis: A Comparison of the Effects of Imidacloprid and Methoxychlor on Rusty Crayfish (Orconectes rusticus) Righting Response
Environmental Studies Senior Capstone
Description
Insecticides are commonly used on agricultural land to limit the adverse effects of insects on crops. These chemicals can leach into nearby aquatic systems and have the potential to affect local species and biodiversity. We examined the righting responses of rusty crayfish (Orconectes rusticus) when exposed to two popular insecticides, Imidacloprid, a neonicotinoid used locally in Adams County, Pennsylvania and Methoxychlor, a pesticide banned in the United States. We hypothesized that the presence of either insecticide would slow the righting response in O. rusticus, which could affect their survival rate in the wild when avoiding predators. We tested two concentrations of Imidacloprid (100μg/L and 200μg/L) and one concentration of Methoxychlor (10μg/L). Additionally, we compared our results with a previously tested concentration of Methoxychlor at 100μg/L (Pettengill 2015). Imidacloprid significantly slowed the righting time of O. rusticus at 200μg/L (p=0.033), and Methoxychlor significantly slowed righting time at 100μg/L (p<0.001). The lower concentrations of Imidacloprid (100μg/L) and Methoxychlor (10μg/L) did not significantly slow righting response. Our results can be used by local management organizations to determine if aquatic systems in Adams County are being affected by pesticide runoff, and therefore deem if action is necessary to protect local biodiversity.
The Crayfish Crisis: A Comparison of the Effects of Imidacloprid and Methoxychlor on Rusty Crayfish (Orconectes rusticus) Righting Response
Glatfelter 102
Insecticides are commonly used on agricultural land to limit the adverse effects of insects on crops. These chemicals can leach into nearby aquatic systems and have the potential to affect local species and biodiversity. We examined the righting responses of rusty crayfish (Orconectes rusticus) when exposed to two popular insecticides, Imidacloprid, a neonicotinoid used locally in Adams County, Pennsylvania and Methoxychlor, a pesticide banned in the United States. We hypothesized that the presence of either insecticide would slow the righting response in O. rusticus, which could affect their survival rate in the wild when avoiding predators. We tested two concentrations of Imidacloprid (100μg/L and 200μg/L) and one concentration of Methoxychlor (10μg/L). Additionally, we compared our results with a previously tested concentration of Methoxychlor at 100μg/L (Pettengill 2015). Imidacloprid significantly slowed the righting time of O. rusticus at 200μg/L (p=0.033), and Methoxychlor significantly slowed righting time at 100μg/L (p<0.001). The lower concentrations of Imidacloprid (100μg/L) and Methoxychlor (10μg/L) did not significantly slow righting response. Our results can be used by local management organizations to determine if aquatic systems in Adams County are being affected by pesticide runoff, and therefore deem if action is necessary to protect local biodiversity.