Long-term monitoring of coastal benthic habitats in the Kerguelen Islands: a legacy of decades of marine biology research

In the current context of climate change, sea-surface temperature variation, sea level rise and latitudinal shifts of currents and hydrological fronts are expected to affect marine biodiversity of the sub-Antarctic Islands, particularly in coastal waters. Characterising the impacts of climate change on marine communities requires recording environmental modifications through the establishment of long-term monitoring. PROTEKER aims at the establishment of a submarine observatory consisting of multi-disciplinary research: oceanography, habitat mapping and species inventories, genetic, eco-physiological and trophic analyses. It also aims to provide scientific standards for the management of the Kerguelen Marine Reserve. Eighteen sampling sites of previous programs were revisited by scuba diving among which eight were selected for monitoring and were progressively equipped. ROV observations and beam trawling have also been conducted for contextualisation. These sites (Morbihan Bay (4), North (2) and South (2) coast) are monitored using photo/video surveys, temperature and salinity sensors, and settlement plots. Sessile communities collected on settlement plots will be characterised yearly through morphological and DNA techniques. Phylogeographical studies of target taxa are being conducted to improve our knowledge of endemicity and connectivity levels among sub-Antarctic islands.