An overexploited Italian treasure: past and present distribution and exploitation of the precious red coral Corallium rubrum (L., 1758) (Cnidaria: Anthozoa)

摘要

The aim of this paper is to supply an overview of all historical and recent knowledge on landings, fishing and geographic distribution of the red coral banks along the Italian coasts in order to make a contribution to the conservation and future management of this resource. Along the Italian coasts, the banks have been exploited for millennia, using non-selective trawling gear that was banned in Europe in 1994. Today, harvesting is allowed only by scuba divers and regulated by specific laws. We examined 153 years of history of coral fishing in Italy, from Unification (1861) to 2014. Data about the coralline fleets and the amount of coral landings were recorded for the considered span of time. From a quantitative point of view, the coral fishing in Italy in the last 150 years has been dominated by the sub-fossil coral reservoirs from the Sciacca Banks (Sicily Channel), where an extraordinary amount of 18,000 tons was collected in 34 years (1875-1888 and 1893-1914). This amount represents about 90% of all red coral harvested along the Italian coast in the last 150 years. Excluding this period, the average annual yield was initially around 100 tons, decreasing to 28 tons 100 years later, therefore demonstrating a severe overexploitation of the resource. The great part of the deep red coral banks was abandoned because harvesting was no longer profitable. Nevertheless, quantitative data suggest that red coral banks, even though overexploited, are still widespread along Italian coasts, mainly in shallow waters. These banks show a remarkable persistence although with a generalised shift towards smaller colony sizes and higher density. The time span necessary in recovering the pristine structure, following the end of the fishing activities, appears very long and the populations of several areas might be unable to re-colonise the old and overexploited banks.