Cotylopus rubripinnis is an amphidromous fish, endemic to the Comoros archipelago, protected (Decree No. 361/DEAL/SEPR/2018), classified as Vulnerable (IUCN), and a key species for ZNIEFFs (Natural Areas of Ecological, Faunal, and Floristic Interest) and for key biodiversity areas defined in the 2017 Indian Ocean Ecosystem Profile – Indian Ocean Region of 2017. In Mayotte, its numbers are rare and scattered (observed in one-third of waterways).
Several pressures are exerted on Mayotte’s waterways: more than 330 obstacles to ecological continuity, numerous domestic uses that disrupt water quality, and the omnipresence of surface water catchments that do not respect sufficient minimum flows to preserve aquatic species.
These pressures threaten the completion of the life cycle of C. rubripinnis: colonisation of waterways by post-larvae for growth, access to river habitats for reproduction, and downstream migration of larvae to the ocean.
This project aims to restore the habitats of C. rubripinnis in terms of habitat quality (physico-chemical, physical), ecological continuity, and quantitative resources. It focuses on the following phases:
- Identification of priority watersheds and associated managers;
- Management and restoration of watercourses: referencing and removal of obstacles to continuity (weirs, log jams, scour holes);
- Targeting of actions to control illegal fishing;
- Targeting of educational outreach actions;
- Environmental education and awareness: visits by different audiences (elected officials, schoolchildren), brochures,
- signs;
- Monitoring of species and the environment, in connection with restoration actions: evolution of flow patterns and substrates (spawning grounds), monitoring of C. rubripinnis populations (juveniles, adults, and downstream flow of pro-larvae).
These actions will make it possible to target and pool the efforts undertaken by local actors, while involving the population.
