Depletion of fish stocks threatens fishing
The overexploitation of fishery resources has led the proportion of endangered or depleted species to drop from around 10% in the 1970s to 24% in 2003. To stop this development, a global network of protected areas covering 20 to 30% of the sea surface.
Sea fishing is beginning to seriously threaten marine biodiversity. A significant proportion of fish stocks and species are now overexploited or even endangered. This is the main finding of the biennial report of the Food and Agriculture Organization of the United Nations (FAO), which has just been published in Rome.
This document, which is the world reference for the assessment of fish stocks and the fishing situation, confirms the stagnation of the volume of fish caught at sea: in 2003, this reached 81 million tonnes (Mt), a level equivalent to that of 1998 (80 Mt) but well below the “peak” of 2000 (87 Mt). More seriously, this report underlines that there is no possibility of expansion and that, "despite local differences, the global potential of marine capture fisheries has been fully exploited, so that more rigorous plans are being made. impose to rebuild depleted stocks and prevent the decline of those which are exploited to the maximum, or almost to the maximum, of their potential ”.
In fact, since 1975, the fishery has undergone a reversal in the state of large fish species: "The proportion of stocks with potential for expansion has continued to decline" (around 24% of the total), while Overexploited or depleted stocks increased from around 10% in the 1970s to 24% in 2003. Among the ten most fished species, seven are considered to be fully exploited or overexploited: anchovy from Peru, horse mackerel from Chile, pollock Alaska, Japanese anchovies, blue whiting, capelin, Atlantic herring.
Network of protected areas
Of course, the situation varies depending on the fishing grounds. The Pacific is less affected than the Atlantic or the Mediterranean which are, for the main species, fully exploited or overexploited. But that does not change the general conclusion of the FAO report. In twelve of the sixteen divided regions selected by the international organization, “the maximum fishing potential has been reached and more cautious and restrictive management is required”.
Climatic factors should not change the situation. We know that they can lead to sudden variations - in one direction or the other - in certain very important stocks, in particular anchovies and sardines. But in the event of overexploitation, and therefore of the fragility of stocks, "the effects of the climate on fisheries are exacerbated, both fish populations and the activities which depend on them then become more vulnerable to the natural dynamics of the environment".
A particular concern relates to deep-sea fish, the exploitation of which has increased significantly over the past ten years, while knowledge of the biology of available stocks and of the diversity of the environment is still very fragmented.
Orange roughy, oreos, red beryx, bromes and abadèche, Antarctic toothfish and other morid cod are thus all the more threatened when they are captured on the high seas, where there is no legal regime to regulate their exploitation.
To protect marine biodiversity, but also to allow stocks of fished species to recover, a necessary condition for sustainable fishing, ecologists gathered at the last World Parks Congress (WPC), held in Durban in July 2003, recommended the establishment, by 2012, of a global network of marine protected areas, restricting or prohibiting locally aggressive fishing and activities. Their recommendation: to make these areas cover a total of 20% to 30% of the surface of the planet's seas. That is 40 to 60 times more than the current network of marine protected areas.
"Guardians of the Seas"
Is this objective realistic from an economic perspective? how much would it cost to set up and maintain such a network?
In a recent study (PNAS of June 29, 2004), an English team led by Andrew Balmford, researcher in the department of zoology at the University of Cambridge, attempted to estimate the cost of setting up global area networks. protected of varying extent and characteristics.
From the analysis of currently protected marine areas, the researchers first identified the main factors governing the cost of protection per unit of protected area, taking into account its distance from the coast and the index of local economic development. The smaller this area, closer to the coast and dependent on a wealthy country, the higher the cost of its protection per square kilometer.
Researchers have also estimated the costs of protecting 20% to 30% at the surface of the world's seas under favorable and realistic conditions of coalescence of protected areas. The result: $ 5,4 billion to $ 7 billion per year, much lower than the $ 15 to $ 30 billion used annually to subsidize fishing. And protecting 20% to 30% of the surface of the world's seas is expected to create 830 to 000 million full-time jobs.
A million “guardians of the seas” facing three or four million fishermen threatened if 30% of the surface of the oceans are prohibited from fishing. "It should be borne in mind that, without protective measures, it is the vast majority of the current twelve to fifteen million fishermen who will be deprived of work in the next decade", underlines Andrew Balmford.
These results show that the preservation of marine ecosystems and the societies that exploit them requires the establishment of protected areas not closed to access, allowing the development of sustainable activities related to the sea, such as ecotourism and coastal maintenance. Such alternative economic activities would allow a retraining of a good fraction of fishermen in all countries.
The limit of 1 000 meters in the Mediterranean
Deep-sea fishing beyond 1 meters should not be developed in the Mediterranean, according to a decision adopted at the end of February in Rome by the General Fisheries Commission for the Mediterranean (GFCM), an intergovernmental body. The move, which is expected to take effect in four months if member countries do not object, is based on a biodiversity and fisheries study conducted by the World Conservation Union (IUCN) and the Global Fund for nature (WWF), who welcomed this progress.
“This is an important measure, the first in the world of this kind. This is a significant step forward towards sustainable fishing in the Mediterranean, ”says François Simard, coordinator of the IUCN global marine program. The exclusion of bottom trawling beyond 1 meters should in particular protect the juvenile shrimp which find their nurseries there. For IUCN, this is a precautionary measure in accordance with the convention on biological diversity.