Abstract
Pharmaceutical pollution is a growing research area due to the improper disposal and lack of proper water treatment. Due to its popularity and high rate of prescription, the antidepressant fluoxetine is particularly prevalent in the environment. It has been found to accumulate in small concentrations in aquatic organisms such as fish, changing their behavioral patterns. To test the effects of fluoxetine on fish, I used 30 Betta splendens. The fish were grouped (n=10) by control, or by treatment with a low dose of fluoxetine (1 ug/L) or a high dose of fluoxetine (10 ug/L), and dosed once a week for three weeks, followed by a two-week non-dosing period to test for any behavioral recovery. Over the course of the experimental trial, feeding behavior was tested using latency to respond to food, the number of pellets investigated, and the number of pellets consumed. Weight was used as a secondary measure to see if there were any differences in the fish growth over the 5-week period. Aggressive behaviors were measured using latency to the mirror, number of broadside displays, and time spent gill and fin flaring. I hypothesized that both low and high doses of fluoxetine would cause decreases in feeding and aggressive behaviors compared to the control and would not recover during the non-dosing periods. I found that fluoxetine decreased the total number of food pellets investigated over the course of the treatment and also increased the latency to respond to an aggressive encounter. However, there is no significant effect of treatment on other aggressive or feeding behaviors. These results indicate that fluoxetine, even at low chronic doses, has some effect on fish behavior. Based on the behavioral results collected from this experiment, it is important that proper disposal of pharmaceuticals is practiced, and further research is conducted to examine improved methods for treating pharmaceuticals in water to prevent incidental exposure to wildlife and humans.
Advisor
Lynn, Sharon
Department
Biology
Recommended Citation
Kellogg, Lane M., "Antidepressant Pollution in Freshwater Organisms: Impacts of Fluoxetine on Betta Fish Feeding Behavior and Aggressive Behavior" (2026). Senior Independent Study Theses. Paper 13532.
https://openworks.wooster.edu/independentstudy/13532
Disciplines
Medicine and Health Sciences
Keywords
Fluoxetine, Behavior, Aggression, Feeding
Publication Date
2026
Degree Granted
Bachelor of Arts
Document Type
Senior Independent Study Thesis
© Copyright 2026 Lane M. Kellogg