Green Turtle Hatchlings Reunion Island @ C. Jean - Kélonia 2011
By Anne-Emmanuelle Landes (1), Léo Pairain (1), Claire Jean (2), Stéphane Ciccione (2)
1. Centre d’Etude et de Découverte des Tortues Marines (CEDTM)
2. Kelonia, l’observatoire des tortues marines de La Réunion
Reunion island, a small volcanic French island located in the southwestern Indian ocean, used to be an important nesting site for green sea turtles (Chelonia mydas) before human colonization. Nesting activity has since almost disappeared due to massive historical hunting, and more recently due to a rapid coastal development. Even if sightings of foraging juvenile turtles have regularly increased in coastal waters over the past three decades, only three sea turtle nests were recorded between 1990 and 2002 on the 39 km of sand beaches in Reunion Island.
In the late 1990s, an existing sea turtle ranch was transformed into a protection center named Kelonia. Because of these very rare nesting events, a pilot beach restoration program was launched in 1999 on a beach in front of Kelonia where no sign of turtle nesting activity had been reported for the past 50 years. This program, initiated with Kelonia's own funds, aimed to restore the back and upper beach vegetation, potentially used by females as a cue for nest site selection.
Some nesting events took place five years later and were encouraging. On this rehabilitated beach, a female laid its eggs four times in 2004, returned in 2007, but unfortunately has not been sighted since. A second identified female successfully nested in 2011 and 2018 near this beach. On another unrehabilitated beach located 20 km north of Kelonia, a nesting activity from a third identified female was also recorded in 2007. This female successfully nested on the same location every three years until 2019. Few other individual nesting events have been also recorded between 2004 and 2006 but the females were not identified. These nesting events encouraged and inspired other similar actions along the coast later on.
The rehabilitation of nesting beaches was targeted in 2015 as a priority action in the national action plan for sea turtles. Since 2017, a larger beach rehabilitation program was conducted by the Centre d’Etude et de Découverte des Tortues Marines (Marine Turtle Discovery and Study Center - CEDTM; www.cedtm-asso.org/vegetation/) and the regional council has been involved as the main funder. This program covered four new sites of the coast and the method implemented focused mainly on:
The actions implemented have been integrated into a strategy of collaboration with more than 50 technical and institutional stakeholders involved in different fields interacting with the program. This has generated additional responsibility and investment in the program and has made it possible to achieve common objectives and protect the natural local heritage.
Field actions were organized and became very popular with the participation of a very diverse public, involving more than 8000 volunteers of which more than 50% were school children. Many complementary tools have been developed such as school programs, conferences, a website, planting activities with institutions, general public and others, information panels on the beaches, a guide published for the managers of the territory, etc. The “awareness raising” part of the program was a great success.
And finally, after a self-funded pilot phase followed by a new phase funded by a lead funder, new complementary funds have been identified after 2020, which shows the enthusiasm and interest in this program. The collaborations led to the integration of the protocol into the projects of different partners at five other coastal sites.
All these projects allow to increase the number of rehabilitated sites on the west coast of the island and so the coastal line favorable to the nesting of marine turtles. The continuity of an attractive coastline enhances the olfactive footprint of the coast, which seems to be helpful in orienting nesting females near the coast.
Reunion Island has a relict breeding population of green turtles, very small and threatened. Rehabilitation is a long-term process and requires continuity of effort, and therefore new funding. Although these significant human and financial resources are deployed for only two turtles to date, the turtle acts as an umbrella species protecting not only nesting habitat but also our coastal ecosystem which is very vulnerable due to our expanding population and urbanization. The involvement of children and the local community has generated a virtuous dynamic that will help sustain conservation efforts over time. Collaboration and bridges between institutions may be a challenge but are rich of opportunity, efficiency, and interest for long-term continuity of effort.
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Ciccione, S. & J. Bourjea. 2010. Nesting beach revegetation and its influence on green turtle (Chelonia mydas) conservation in Réunion Island. Indian Ocean Turtle Newsletter No. 11: 2-4.
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Landes, A-E. Pairain L., Gaud P., Gobeaut C., Dalleau M., Jean C. & Ciccione S. 2020. Guide d’aménagement du littoral pour améliorer la qualité des sites de pontes des tortues marines. CEDTM. La Réunion. 72p.
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Last updated on 06 September 2022