Assessing the impact of diving in coralligenous communities : The usefulness of demographic studies of red gorgonian populations

摘要: Coralligenous communities are an important “hot spot” of Mediterranean biodiversity. These presently threatened by a combination anthropogenic impacts partly related to global change. Managers MPAs increasingly concerned about the capacity coralligenous endure crowds divers, and there is call for descriptors quantitative methods estimating this capacity. A good indicator detect on should gather following essential traits: be long-lived, clonal, engineering species displaying erect shape large size in order facilitate monitoring. Among main taxonomic groups coralligenous, gorgonians display several advantages and, study, red gorgonian Paramuricea clavata was selected as model evaluate effects diving impact climate change communities. We present three cases study demographic monitoring populations affected 1999 mass mortality event (Port-Cros) subjected high activity (Medes Islands Cap de Creus). Finally, combining all these data we simulate interacting divers damage events persistence populations. The results long-term permanent plots allowed showing that although affects significantly populations, effect has more significant Port-Cros suffered 60% biomass loss not been recovered eight years. Simulations showed both disturbances can have lasting future viability As assemblages only one facies communities, other detecting Nevertheless, development similar approaches would difficult than gorgonians.