Scents and scents-ability: pollution disrupts chemical social recognition and shoaling in fish

摘要

Chemical cues are of enormous importance in mediating the behaviour of animals, enabling them tonavigate throughout their habitats, to detect the presence of predators or prey and for social recognition—identifying and discriminating between conspecifics. In many species of freshwater fish, social recognitionis known to be based primarily on chemical cues. Such recognition mechanisms are vulnerable todisruption by the presence of anthropogenic contaminants in the aquatic environment. Here we show thatacute exposure to low, environmentally relevant dosages of the ubiquitous contaminant, 4-nonylphenol,can seriously affect social recognition and ultimately social organization in fishes. A 1 hour 0.5 μg 1-1 dosewas sufficient to alter the response of members of a shoaling fish species (juvenile banded killifish, Fundulusdiaphanus) to conspecific chemical cues. Dosages of 1-2 μg 1~(-1)caused killifish to orient away from dosedconspecifics, in both a flow channel and an arena. Given the overall importance of shoaling as an adaptivestrategy against predators and for locating food, it is likely that its disruption by anthropogeniccontaminants would have serious implications for fishes' fitness.