Chronic playback of boat noise does not impact hatching success or post-hatching larval growth and survival in a cichlid fish.

Rick Bruintjes,Andrew N Radford

doi:10.7717/peerj.594

Abstract

Anthropogenic (man-made) noise has been shown to have a negative impact on the behaviour and physiology of a range of terrestrial and aquatic animals. However, direct assessments of fitness consequences are rare. Here we examine the effect of additional noise on early life stages in the model cichlid fish, Neolamprologus pulcher. Many fishes use and produce sounds, they are crucial elements of aquatic ecosystems, and there is mounting evidence that they are vulnerable to anthropogenic noise; adult N. pulcher have recently been shown to change key behaviours during playback of motor boat noise. Using a split-brood design to eliminate potential genetic effects, we exposed half of the eggs and fry from each clutch to four weeks of playbacks of noise originally recorded from small motor boats with the other half acting as a control (receiving no noise playback). There was no significant effect of additional noise on hatching success or fry survival, length or weight at the end of the exposure period. Although care should be taken not to generalize these findings on a single species from a laboratory study, our data suggest that moderate noise increases do not necessarily have direct negative impacts on early-life survival and growth. Further studies on a range of species in natural conditions are urgently needed to inform conservation efforts and policy decisions about the consequences of anthropogenic noise.

Highlights

Noise-generating human activities, such as transportation, urbanisation and resource exploitation, have altered the acoustic environment in many terrestrial and aquatic environments around the globe (Normandeau Associates Inc., 2012; Watts et al, 2007)
We found no evidence in our laboratory study using Neolamprologus pulcher that hatching success or fry survival and size four weeks post-hatching were detrimentally affected by chronic exposure to playback of additional noise originating from recordings of small motor boats
These findings are in line with those of Wysocki et al (2007), who did not detect any significant impact of high continuous aquaculture noise on the growth or survival of rainbow trout (Oncorhynchus mykiss), but contrast the work of Banner & Hyatt (1973), who reported decreased hatching success and larval growth in fish reared in tanks with high continuous sound-pressure levels from water-pump noise

Summary

Introduction

Noise-generating human activities, such as transportation, urbanisation and resource exploitation, have altered the acoustic environment in many terrestrial and aquatic environments around the globe (Normandeau Associates Inc., 2012; Watts et al, 2007). How to cite this article Bruintjes and Radford (2014), Chronic playback of boat noise does not impact hatching success or post-hatching larval growth and survival in a cichlid fish. We investigate how chronic playback of additional noise, from original recordings of motor boats, affects hatching success and the growth and survival of young in a model fish species Neolamprologus pulcher. Experimental investigations of how anthropogenic noise impacts early-life in other organisms are rare (but see Banner & Hyatt, 1973; Caiger, Montgomery & Radford, 2012; McDonald et al, 2014; Nedelec et al, 2014; Wysocki et al, 2007)

Methods

Results

Conclusion