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Physa integra antipredator response in changing temperature and pH

Project Abstract: 
Physella acuta snails detect predators in their environments and perform antipredator behaviors. One response is the “crawl-out response,” where they crawl to or above the water line to avoid the danger of the predator. Crayfish, a natural predator of snails, induce this response. This study aims to examine how climate change impacts the antipredator behavior of Physella acuta, with respect to increasing temperature and decreasing pH. We hypothesize that the response times will be slower for snails exposed to extreme heat, acidity, and a combination of both factors. Another hypothesis is that they will develop a secondary antipredator behavior. So far, there has been evidence to suggest that the response times are slower, but not enough data has been collected by this point in time to make this a statistically significant claim. Additionally, a secondary antipredator response has been observed, but not enough data has been collected by this point in time to suggest this correlation is statistically significant.
Investigators: 
Status of Research Project: 
Years Active: 
2022
Methods: 
Physella acuta snails are collected in Douglas Lake. I collect them by snorkeling, picking them up with my hands and placing them in a bucket I have with me, and then I walk them to my space in the boat well. They are stored in a holding tank until they are moved to a treatment tank of either increased heat, lowered pH or both. Crayfish, a natural predator of the snails, were collected at the beginning of the study; they are kept in individual tanks. Their purpose is to contaminate their tank water to contain chemical cues of crayfish to use to trigger the antipredator response in snails during experimentation. Each day, I take the pH and temperature of all tanks. The snails stay in their treatment tanks for 3 days before experimental trials. Then they are placed into separate 600mL beakers, containing 100mL crayfish water and 200mL of their treatment water. I time how long it takes for them to perform an antipredator response. After experimentation, the snails are placed into a secondary holding tank. They are held there until the end of the study; we keep them for the duration of the study to avoid potential recapture.