Due to low levels of antidepressant medications entering bodies of water, researchers found that crayfish behaviors are changing.
According to a new study from the University of Florida, crayfish exposed to these drugs behaved in ways that could make them more vulnerable to predators.
“Crayfish exposed to the antidepressant came out into the open, emerging from their shelter, more quickly than crayfish not exposed to the antidepressant. This change in behavior could put them at greater risk of being eaten by a predator,” said assistant professor Lindsey Reisinger, a co-author of the study.
The scientists recreated a crayfish’s natural environment in a lab with artificial streams similar to their usual environment. A selective serotonin reuptake inhibitor (SSRI) was the antidepressant used in the study. This setup allowed them to control the antidepressant amount in the water and study crayfish behavior.
Researchers used a "Y-maze," which has an entrance that branches into two lanes like the letter Y. A crayfish was put in a container at the entrance to the maze.
When the container opened, researchers timed how long it took for the crayfish to leave, where it would either go through to the lane that held chemical cues as food, or the other, that signaled the presence of another fish.
Researchers recorded which direction the crayfish chose and how long.
Through this technique, the researchers found that crayfish exposed to antidepressants left the shelters earlier and spent more time looking for food.
“The study also found that crayfish altered levels of algae and organic matter within the artificial streams, with potential effects on energy and nutrient cycling in those ecosystems,” A.J. Reisinger, lead author of the study and an assistant professor in the soil and water sciences department, said.
Medications can enter the environment through improper disposal or through excreting amounts using the bathroom, Reisinger said.
“The answer is not for people to stop using medications prescribed by their doctor. One big way consumers can prevent pharmaceuticals from entering our water bodies is to dispose of medications properly,” he said.
