The sustainability principle
Sustainability is the principle demanding that exploited resources be renewable and that the rate at which they are used does not exceed their renewal rate. This notion can be compared to that of financial capital from which only the interest can be withdrawn. Given that the resources of fisheries are communal, they do not lend themselves to sustainable exploitation and, generally, their capital is reduced rather than accumulating interest. In the vicious circle of unsustainability, capital decreases, thus generating less interest. This causes increased pressure on capital and an inexorable decline in the production of surpluses.
“Renewable resources, by definition, possess self-regeneration capacities and can provide man with an essentially endless supply of goods and services.”
C. W. Clark, The Economics of Overexploitation
The key international agreements governing high-seas fisheries (those taking place outside the 200 nautical mile Exclusive Economic Zone) call for the adoption of the sustainable stock management principle (1992 Convention on Biological Diversity, 1995 United Nations Agreement on Straddling Fish Stocks) and for engagement to end destructive fishing practices by 2012 (FAO code of conduct for responsible fisheries, 1999 Rome Declaration, 2002 Johannesburg Declaration).
At international level, the sustainability principle is a legal obligation under the Law of the Sea Convention. It is reaffirmed in the “plan of action” from the 2002 World Summit on Sustainable Development in Johannesburg. (Chapter IV, Art. 31a: Maintain or restore stocks to levels that can produce the maximum sustainable yield with the aim of achieving these goals for depleted stocks on an urgent basis and where possible not later than 2015).
Explicit reference to the sustainability principle is made in Council Regulation (EC) No 2371/2002 of 20 December 2002 on the conservation and sustainable exploitation of fisheries resources under the Common Fisheries Policy: “the Common Fisheries Policy should be improved to ensure the long-term viability of the fisheries sector through sustainable exploitation of living aquatic resources based on sound scientific advice”.
Clark, C. W., The Economics of Overexploitation. Science, 17th August 1973, Vol. 181. No 4100, pp 630-634.
Mangel, M., Hofman, R. J., Norse, E., Twiss, Jr., J.R., Sustainability and EcologicalResearch. Ecological Applications, Volume 3, Issue 4 (Nov., 1993), 573-575.