Recovery of Olfactory Mediated Behaviours of Fish from Metal Contaminated Lakes

Fish mediate many biological processes by olfaction, which can be impaired by contaminants (i.e. metals). While the olfactory recovery of fish from metal contaminated lakes if subsequently cultured in clean water has been shown at the neurophysiological level, the recovery potential of olfactory mediated behaviours remains unknown. To study behavioural recovery of fish from metal contaminated lakes, wild yellow perch (Perca flavescens) were collected from two metal-contaminated lakes (Ramsey and Hannah lakes) in the metal-mining district of Sudbury, ON, Canada and cultured in clean water from a reference lake (Geneva Lake) for another 24 h. Olfactory mediated behaviours of the test organisms were tested using avoidance responses to conspecific skin extract. While olfactory mediated behaviours of fish from Ramsey Lake (low contamination) recovered after 24 h in clean water, recovery could not be observed in fish from Hannah Lake (high contamination). These results demonstrate that the recovery of behavioural deficits of fish from metal contaminated lakes is depending on the habitats’ metal concentration.