Larval fish exposure to harmful algal blooms causes long-term effects on sensorimotor integration

Cyanobacteria produce harmful algal blooms (HABs) in freshwater environments that have been linked to disruptions in neurofunction, growth, and survival. Cyanotoxins produce non-lethal, but substantial alterations in the central nervous system and behavior. Little is known about how HAB-induced changes in the behavior of affected organisms influence fitness. This deficit in knowledge is important because the effects of exposure to neurotoxins on species interactions is critical in accurately producing risk assessments. The aim of this project was to evaluate the short- and long-term effects of exposure to 2,4-diaminobutyric acid (DABA) on cognitive and motor performance of fish during hunting events. The central hypothesis is that chronic, low-dose exposure to cyanotoxins alters outcomes of species interactions through deterioration in sensorimotor feedback during prey-capture events. To test this hypothesis, data were collected on the prey-tracking performance of larval (21 days) and adult (7-8 months) fathead minnows, Pimephales promelas, during hunting events under lab conditions. Foraging efficiency and prey-capture trials indicated that exposure to DABA was associated with a significant reduction in prey consumption. This suggests these effects would also occur in wild populations. Such impacts are important because they have the potential to alter the dynamics of aquatic populations and communities.