Decreased retention of olfactory predator recognition in juvenile surgeon fish exposed to pesticide
Abstract
Dory, the animated surgeonfish created by the Pixar Animation studios, famously suffered from short-
term memory loss leading to many adventures. In reality, many fishes have excellent cognitive abili-
ties and are able to learn and retain important information such as the identity of predators. However, if
and how cognition can be affected by anthropogenically altered oceanic conditions is poorly understood.
Here, we examine the effect of a widely used pesticide, chlorpyrifos, on the retention of acquired
predator recognition in post-larval stage of the surgeonfish Acanthurus triostegus. Through associative
learning, post-larvae of A. triostegus were first observed to forage significantly less in the presence of
conspecific alarm cues and alarm cues associated to a predator's odor. The retention of this anti-predator
behavior was estimated to last between 2 and 5 days in the absence of pesticide. However,
environmentally-relevant concentrations of chlorpyrifos (1 m g.L ?1 ) induced the loss of this acquired
predator recognition. This reduced ability to recognize learned predators is discussed as it may lead to
more vulnerable fish communities in coastal areas subjected to organophosphate pesticide pollution.