Borendy 2012. Bilan de l’état de santé des récifs par stations vidéo rotatives STAVIRO

• Conducted within the AMBIO project, this work deals with coral reef fish communities and associated habitats, in the New Caledonian lagoons. It relies on remote unbaited underwater video observations, using the STAVIRO rotating technique. The study takes place in the Borendy area, encompassing two no-take marine reserves Nemou and Moindé-Ouémié. The sampling design covers the entire area, and was stratified according to reef geomorphology and protection status. 66 stations were validated within 3.5 days. They were analyzed to characterize at each station habitat and fish, from a species list that includes fished, emblematic and functionally important species. • 32 indicators were computed and mapped (Sextant server). 24 indicators were analysed using the PAMPA computing tool. Outcomes were organized in a dashboard per management objective (biodiversity conservation and fisheries management). • 111 fish and 1 turtle species, belonging to 21 families were observed. Surgeonfish and parrotfish were most frequent (90% et 94% of stations), and then butterflyfish and siganids (80% and 79%). Groupers and emperors are frequent (56% et 54% des stations)(salmon trout at 45% of stations). • Overall, butterflyfishare both diversified (17 species) and abundant, indicating a good ecological status of the reef, but emblematic species are rare.Living coral was found at 97% des stations, with high cover values. • At the area scale, the species assemblage significantly depends on both reef type and protection status. Species richness and overall density are significantly higher on reefs under ocean influence, and lower on fringing reefs. • Surgeonfish, parrotfish and groupers, as well as carnivores are less abundant in Port-Bouquet Bay than more southern. In this Bay, the density of surgeonfish and parrotfish is significantly lower in reserve. In Moindé-Ouémié, groupers are significantly more abundant in the reserve. No differences between protected and unprotected areas were found for the other families. • Butterflyfish are both more diversified and more abundant in both reserves, but this is only significant for Nemou. At Moindé-Ouémié, both indicators exhibit higher values irrespective of the protection status. • Target species are abundant over the entire zone. No significant differences were found inside/outside reserves. Biodiversity ; Fish ; Habitat ; Underwater video; STAVIRO ; Monitoring and assessment; Marine Protected Area ; MPA; World Heritage; Coral reefs; New Caledonia ; Indicator; Dashboard ; Map