Changes in distribution patterns of two vulnerable fish species (Epinephelus marginatus and Sciaena umbra) in the Scandola marine reserve (Corsica, NW Mediterranean): a possible effect of increased boat tourism
Corresponding author: Mireille Harmelin-Vivien, mireille.harmelin@mio.osupytheas.fr
How to cite: Harmelin-Vivien, M., Le Diréach, L., Charbonnel, E., Dominici, J.-M., Ganteaume, A., Harmelin, J.-G., Lelong, P., Personnic, S., & Cottalorda, J.-M. (2023). Changes in distribution patterns of two vulnerable fish species (Epinephelus marginatus and Sciaena umbra) in the Scandola marine reserve (Corsica, NW Mediterranean): a possible effect of increased boat tourism. Cybium, 47(2): 123-137. https://doi.org/10.26028/CYBIUM/2022-015
The populations of two iconic fish species, the dusky grouper Epinephelus marginatus and the brown meagre Sciaena umbra, were recorded at 13 sites inside and outside the marine reserve of Scandola, Corsica (NW Mediterranean), according to three levels of protection (integral reserve, buffer zone and unprotected zones) in summer 2012 and 2018. No change in mean abundance with protection level was recorded for E. marginatus between years but relocation of individuals was observed among sites. In contrast, S. umbra mean abundance decreased in the integral reserve in 2018. A particular abundance decline was recorded in 2018 at certain sites in the integral reserve for both species (dusky grouper: –63%; brown meagre: –88%). Different hypotheses explaining the changes observed are discussed (depth refuge, disease, poaching, artisanal fisheries and boat tourism). The increase in marine noise pollution generated by motorboats in summer during these species’ reproduction period, by disturbing their acoustic communication and mating behaviour, could be a cause of depopulation at certain sites.