Behavioural responses in a congested sea : an observational study on a coastal nest-guarding fish

Mascolino, S; Mariani, S; Benvenuto, C

Abstract

The deleterious effects of anthropogenic noise on animal communication are nowadays recognised, not only in urban environments but also in terrestrial habitats and along coasts and in open waters. Yet, the assessment of short- and long-term exposure consequences of anthropogenic noise in marine organisms remains challenging, especially in fish and invertebrates. Males of the Mediterranean damselfish Chromis chromis vocalise and perform visual displays (multimodal communication) to attract mates. The frequency-range of courtship vocalisations overlaps with low-frequency noise generated by maritime activities, resulting in a reduced detection distance among conspecifics. We quantified the number of courtship-related visual displays performed by males living in areas with different levels of maritime traffic. We also tried to manipulate ambient noise in the field to test male short-term response to increased noise levels. Males living in busier areas (near to a harbour) performed significantly more visual displays than those living in less congested areas. When exposed to artificially-increased ambient noise level (playback of boat noise), males did not adjust the number of visual displays accordingly. Yet, we note how assessing the actual effect of maritime traffic in marine populations in their natural environments is particularly difficult, as the effects of boat noise cannot be easily disentangled from a variety of other intrinsic or environmental factors, discussed in the paper. We thus present suggestions to obtain more robust analyses of variations of courtship behaviours in territorial fishes. We hope this will facilitate a further understanding of the potential long-term effects of anthropogenic noise, whose analyses should be prioritised in the context of environmental impact assessment, resource management and biodiversity conservation.

• Journal Article Type: Article
• Acceptance Date: Nov 22, 2019
• Online Publication Date: Dec 17, 2019
• Publication Date: Dec 17, 2019
• Deposit Date: Nov 28, 2019
• Publicly Available Date: Dec 20, 2019
• Journal: European Zoological Journal
• Electronic ISSN: 2475-0263
• Publisher: Taylor and Francis Group
• Volume: 86
• Issue: 1
• Pages: 504-518
• DOI: https://doi.org/10.1080/24750263.2019.1699611
• Publisher URL: https://doi.org/10.1080/24750263.2019.1699611
• Related Public URLs: https://www.tandfonline.com/toc/tizo21/current
• Additional Information: Funders : Irish Research Council (IRC); Projects : Embark Initiative; Grant Number: RS/2010/2106