Noise Affects Multimodal Communication During Courtship in a Marine Fish

Karen de Jong,M. Clara P. Amorim,Paulo J. Fonseca,Katja U. Heubel

doi:10.3389/fevo.2018.00113

Abstract

Selection pressures on signals can be substantially modified by a changing environment, but we know little about how modified selection pressures act on multimodal signals. The currently increasing levels of anthropogenic noise in the ocean may affect the use of acoustic signaling relative to other modalities. In the Painted Goby (Pomatoschistus pictus), visual and acoustic signals are associated during courtship behavior, but females usually rely more heavily on acoustic signals than on visual signals in mate choice. In an aquarium experiment, we compared male courtship behavior and female spawning decisions between silent treatments and treatments with additional noise. We found that the relationships between male characteristics, male visual and acoustic courtship, and spawning success were affected by noise. A path analysis revealed that females pay more attention to visual courtship in noisy circumstances compared to control. We conclude that environmental stressors can cause shifts in the use of different signaling modalities for spawning decisions and discuss how selection pressures on multimodal signals may change with increasing noise-levels.

Highlights

The degree to which a signal is effective in carrying information to a receiver can be substantially modified by a changing environment
Male acoustic courtship frequency was significantly correlated with male visual courtship frequency and male size had a significant effect on male visual courtship frequency (Figure 3B)
We found that noise affects the relationship between male courtship behavior and female spawning decisions in the Painted Goby

Summary

Introduction

The degree to which a signal is effective in carrying information to a receiver can be substantially modified by a changing environment. Signaling individuals may switch to different modalities that are not, or are less affected by environmental changes, such as found in tree frogs that produce more visual signals when background noise is high (Grafe et al, 2012). In those cases where the receiver benefits from the information contained in the signal (e.g., mate choice), the receiver may adapt to a loss of signal efficacy by switching its attention to alternative signals or cues, such as stickleback females that pay more attention to chemical than visual signals in a turbid environment (Heuschele et al, 2009)

Methods

Results

Conclusion