Behavior of Eastern Mosquitofish from Areas of Varying Hydroperiod in the Everglades Ecosystem

Behavior of Eastern Mosquitofish from Areas of Varying Hydroperiod in the Everglades Ecosystem

We explored fish behavior and migration in the Everglades. During the wet season, most areas are inundated with water. However, during dry season many areas dry out forcing fish to locations with more permanent water. If the fish do not migrate to deeper areas they die by getting stranded or are eaten by birds. We were interested in understanding how the behavior of mosquitofish varies between different sites of varying hydroperiod. We hypothesized that fish from areas that dry annually would have adaptations increasing their likelihood of surviving the drydown. Lake Okeechobee does not dry out therefore we predicted that the fish might display different behaviors. We collected Eastern Mosquitofish from Lake Okeechobee and short hydroperiod wetlands in the Everglades. We filmed them exploring an artificial environment in the lab to ascertain differences in their “boldness” and othermeasures of their behavior. Fish from Lake Okeechobee swam a greater distance and longer fish swam further. As the dry season approached fish from the Everglades, but not fish from Lake Okeechobee, increased their exploration. This met our predictions that fish from areas that dry must change behavior to increase survival rates. None of our other variables varied among treatments. Understanding mosquitofish migration and behavior in the Everglades is vital to develop restoration projects to restore hydrology. Management of populations of prey organisms and their habitats in critical for restoring populations of wading birds and other threatened predators.