Damage by fishing activities to the Gorgonian coral Paramuricea clavata in the Ligurian Sea

1. The analysis, by means of line transects, of a Paramuricea clavata (Anthozoa: Gorgonacea) population forming a facies of the Mediterranean coralligenous community along the Portofino Promontory (Ligurian Sea, Italy) evidenced a high per cent of lesions inflicted to the gorgonian coenenchyme by anchoring and fishing activities. 2. This damage favours the development of aggregates of epibionts (mainly hydroids and bryozoans) which leads to greater mechanical stress through increased resistance of the colonies to water movement; where polychaetes and nematodes colonize the denuded skeleton, their burrowing activity weakens the colony. 3. In situ tissue regeneration experiments suggested that aggregation of epibionts can develop only if the injuries result, from continuing abrasion. 4. Injuries caused by anchoring and fishing can therefore be considered the major cause of mortality of Paramuricea clavata in the Portofino Promontory. 5. Paramuricea clavata re‐colonizes experimentally denuded areas slowly and colonies take many years to reach the size of existing individuals and can be damaged easily by fishing and anchoring. 6. Special protection is needed for this key species of Mediterranean coral at Portofino Promontory, which is proposed as a Natural Marine Park. © 1997 John Wiley & Sons, Ltd.