Fish farm effluents cause metabolic depression, reducing energy stores and growth in the reef-forming coral Lophelia pertusa

Cold-water corals (CWCs) have come under increasing pressure from human activities over the last decades. Of particular concern in Norway is potential impact of open net pen aquaculture on CWC reefs formed by Lophelia pertusa, a threatened and declining habitat. We conducted 1 yr situ transplantation experiment corresponding field measurements 2 located close to fish farms elucidate impacts particulate organic waste released coral colonies. Our study provided new evidence negative effluents L. pertusa ecophysiology. After yr, both naturally occurring transplanted corals, at distances ranging 250 m km downstream what would be regarded as an average-sized Norwegian farm, exhibited depressed metabolic rates compared outside main depositional footprint farms. The depression impeded energy acquisition, reducing growth reserves up 70 50%, respectively. No clear threshold for significant biological could detected along distance gradient. Instead, gradual decrease rates, lipid occurred with modelled sedimentation rate farm. strong statistical correlation between oxygen consumption, growth, stores implies that predictions short-term ecophysiology reef development may achievable future. This significantly improve ability management make informed decisions licensing near reefs.