Distribution patterns of ocellated eagle rays, Aetobatus ocellatus, along two sites in Moorea Island, French Polynesia

Berthe C., Waqalevu V.P., Latry L., Besson M., Lerouvreur F., Siu G., Lecellier G., Rummer J.L., Bertucci F., Iglésias S., Lecchini D.

Published date: December 2018
Volume: 42
Number: 4
Pagination: 313-320
Publisher: Société Française d'Ichtyologie
doi: https://doi.org/10.26028/cybium/2018-424-002

Elasmobranchs are critical to tourism industries worldwide. In French Polynesia, where ecotourism is the second most important industry, little is known about the spatiotemporal distribution of eagle rays. This study represents the first investigation into habitat use and behaviour of ocellated eagle rays (Aetobatus ocellatus) in French Polynesia focused on two sites with different levels of anthropogenic noise. Environmental variables and biological data were recorded over a one-year period to explore the distribution patterns of 113 eagle rays identified at these sites. Results revealed distinct patterns in habitat use between the two sites, with the eagle ray population structured according to ontogenetic stage. Young rays preferred the site with lower levels of noise pollution, where they foraged at the end of the day. Adult eagle rays gathered in the mornings at the louder site, where the only noticeable activity was group swimming. Overall, our results could help conservation initiatives to manage this important species in French Polynesia, and potentially other coral reef areas, especially in the context of rising human impacts on the environment.

Keywords: Animal behaviour - Anthropogenic activities - Ontogenetic partitioning - Photo-identification - Rays
PDF available for everyone