Hyehen 2012. Bilan de l’état de santé du récif par stations vidéo rotatives STAVIRO

This work deals with fish communities and associated habitats, in the context of New Caledonian coral reef ecosystems. It was conducted within the AMBIO project. The study relies on remote underwater video observations, using the STAVIRO rotating technique. The study takes place in the Hienghene area, an area (Eastern Coastal Area) part of the World Heritage site “New Caledonian lagoons”. It encompasses two Marine Protected Areas, Do Himenand Yeega. The sampling design covers the entire area, and was stratified according to reef geomorphology and protection status. 105 stations were validated within 4,5 days. They were analyzed to characterize the habitat surrounding each station, and fish communities, based on a species list that includes fished species, emblematic species and functionally important species. 23 indicators were computed and corresponding maps were constructed (available on a Sextant server). Each indicator was plotted and analyzed using the PAMPA computing tool. Outcomes were organized in a dashboard for each management objective (biodiversity conservation and fisheries management). Most stations were conducted on rocky substrate: 32% of stations in the living coral habitat and 47% on detritic substrate, and only 21% in soft bottoms habitats. 109 fish species, and one turtle species, belonging to 19families were observed. Surgeonfishes and parrotfishes are the most frequently observed families (90% and 75% of stations) followed by butterflyfishes (54%), mullids (48%) and wrasses (45%). Nine families were observed in morethann20% of stations. Seventeen species of butterflyfish were observed, several turtles, humphead wrasses and sharks, indicating an overall goodhealth of the reef ecosystem. Herbivores and carnivores dominate the fish assemblage and are quite abundant in coral-rich habitats; carnivores are significantly more abundant in the both reserves, whereas this is only at Do-Himen(reserve on the barrier reef) for herbivores. Species assemblage significantly differs between habitats and to a lesser extent on protection status. Most indicators display higher values inside reserves, these differences are significant for species richness (SR) in living coral habitat, and for the SR of surgeon fish and parrotfish. Indicator values are generally higher in the DO-Himen reserve than in Yeega which is closer to the shore.