CRIOBE

Since its foundation , the CRIOBE discerned the scientific stake in the observation of the stocking temporal fluctuations as well as the reefs populations on the long term.

The first data was collected as early as 1971 on the privileged area of Tiahura, north-west of Moorea even if the continuing long term temporal track started in 1987, more than 2 decades ago.

On the present day, the Tiahura radial is one of the most investigated reef spot in the world. Long term programs are conducted for over 20 years in this area. Later those programs have been geographically extended all over Moorea and then in the 5 state’s archipelagos. Finally, as part of the Polynesian Mana Network (Global Coral Reef Monitoring Network), it reached the small states or neighboring insular territories.

Benthic invertebrate were mainly concerned by this tracking (especially scleractinar corals) as well as fishes stocks .

Others long term tracking( ou monitoring) are also carrying out on explanatory variable concurrently with living being surveys. Those surveys concern physic-chemical parameters (see water temperature, hydro dynamism), chemical parameters (mineral salt, dissolved gas), natural disturbance linked parameters (cyclones, predators proliferation…) and others linked with local human pressure and perturbations (urbanization, cost line alteration, resource exploitation).

The PGEM

The Protected Marine Areas surveillance program is managed by the CRIOBE with the BACIPS method (Before After Control Impact Paired Series). The survey campaigns are conducted twice a year on the benthos and fishes since 2004 will allow at the end to rationally estimate the Protected Marin Areas efficiency as a resource protector.

The Acanthaster Survey

Regularly since 2006, annual surveys are realized to understand the Planci Acanthaster invasive phenomena that affected the whole Society archipelagos high Isles.

Sylvie Geoffroy (EPHE Diploma, Perpignan) testimony :

“The Planci Acanthaster (“Taramea” in Tahitian), apeard in the ocean approximately 500 millions of years ago, has been scientifically observed for the first time in the Suva Isles (Fidji) in 1930. This coral avid eater star is also frequently seen on the French Polynesian coral reefs where cyclic demographic explosion occur. The former massive explosion, preceding the actual one affecting the Society Isles, occured from end of the 70’s to beginning of the 80’s. At the begining of the actual phenomena observed in Moorea since 2004, several studies have been conducted by the CRIOBE (Thibault Rauby in 2005, Thierry Lison de Loma, Yannick Chancerelle, et Franck Lerouvreur in 2006, Céline Stievenart in 2007). Those studies prove and quantify the high density phenomena rising on Moorea’s outer slopes and lagoons since 2004 with a census realized on the Island’s scale . Consequences are a high coralline mortality (diminution of the coralline surface) and a reef habitat destruction which will have effects on others reef stocks and in the long term (fish, molluscs, etc.).

In the first place, the main objective of my study is to continue the Taramea density spatio-temporal survey that started in Moorea in 2006 and to analyze the potential mechanisms of their overgrowth at the French Polynesia scale.”

The Manta-tow technique allows fast tracking on a long distance by towed scuba dive to monitor geographically large scale phenomena like the Planci Acanthaster (Taramea) invasion since 2006. This technique has also been used during the coralline whitening episodes that arise during some abormally hot austral summers.

The Polynesia Mana Network

The Polynesia Mana Network managed by the CRIOBE concerns French Polynesia and small states or neighboring insular territories : Cook Islands, Kiribati, Tokelau, Tonga, Niue, Wallis et Futuna. In each of these territories, a periodic monitoring on coral stocks and fish is achieved.