Effects of temperature on acoustic and visual courtship and reproductive success in the two-spotted goby Pomatoschistus flavescens

Abstract

Fish are ectothermic and small changes in water temperature could greatly affect reproduction. The two-spotted goby is a small semi-pelagic species that uses visual and acoustic displays to mate. Here, we studied the effect of temperature (16 and 20 °C) on acoustic and visual courtship and associated reproductive success in 39 males. Temperature influenced male visual courtship performed outside the nest, but it did not influence calling rate and the number of laid eggs. Interestingly, the number of sounds (drums) was the sole predictor of spawning success. These findings suggest that exposure to different temperatures within the species’ natural range affect courtship behaviour but not its reproductive success. We propose that finding the link between acoustic behaviour and reproduction in fishes offers the opportunity to monitor fish sounds both in the lab and in nature to learn how they respond to environmental changes and human impacts, namely global warming.