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Inventory field work

M
anu conducts several ecological assessments throughout the french polynesian islands, from logistics to fieldwork.
One example, in June 2012, a team of scientists (botanist, marine biologist and ornithologists) plus one local guide reached three uninhabited atolls south of the Tuamotu (Morane, Vahanga, Tenarunga). These atolls being so remote, very few boats come alongside. The purpose of this mission was to draw up an inventory of the existing fauna and flora for a rat eradication project.



MORANE ATOLL

Photo : Morane atoll is localised in the Southern Tuamotu archipelago, 1400km East of Tahiti and 160km South of the nearest atoll (Maria).

Photo credits : Lee Radford

Morane is a safe haven for birds. It hosts no introduced predators such as rats or cats. Since 2007, Marie-Hélène Burle studies the Tuamotu sandpiper, a.k.a titi(Prosobonia cancellata), as her PhD topic (University of Vancouver). The titi is endemic to the Tuamotu islands and is on the brink of extinction. With the help of her assistant, François Sanz, she estimated the titi population of Morane at 500 birds, which is the largest known congregation of that species.
Besides, Thomas Ghestemme and Lee Radford – Manu association members – have been studying the tutururu a.k.a. Gallicolombe erythroptera, also endemic to the Tuamotu and critically endangered (CR). Looking for it thoroughly, they could only spot two tutururu on Morane. Thomas is worried for the atoll holds allegedly half of the total tutururu population, i.e. 50 birds. On a more positive note, there was an abundance of seabirds.


LES ATOLLS DE VAHANGA ET TENARUNGA
The Acteon group, is a subgroup consisting of four Tuamotu islands : the atolls of Tenararo, Vahanga, Tenarunga and Matureivavao ( from North to South ),each only a few kilometers apart.
Tenararo is well preserved, free of introduced predators and therefore shelters many bird species, amongst which the titi and the tutururu.

In contrast, Vahanga used to be a copra-producing area and is now protected and his access prohibited, whereas Tenarunga is still being exploited for copra.
Men accidentally introduced rats on these two atolls. They are a major threat to eggs and chicks. Steve Cranwell states that the lower bird density is directly related to the presence of rats. Therefore, the SOP is considering eradicating them entirely from these atolls.

The team identified two land bird species, six seabird species (one being the Murphy’s petrel, Pterodroma ultima) and three wader species including the Bristle-thighed curlew (Numenius tahitiensis) listed as a vulnerable species (VU).

On the botanic side, Fred Jacq mentions that, since the year 2000, the abandonment of coconut groves in Vahanga has allowed the indigenous plants to recolonise the atolls.