The depletion of fisheries threatens fish stocks
The overfishing has led the proportion of endangered or depleted from approximately 10% in 1970 years 24% in 2003. To stop this trend, it would create a global network of protected areas covering at 20 30% of the sea surface.
Sea fishing begins to seriously threaten marine biodiversity. A significant proportion of fish stocks and species are now overfished or endangered. This is the main conclusion of the biennial report of the Food and Agriculture Organization (FAO), which has just been published in Rome.
This document, which is the world reference for the assessment of fish stocks and the fisheries situation, confirms the stagnation of the volume of fish caught at sea: in 2003, it reached 81 million tonnes (Mt), one level equivalent to that of 1998 (80 Mt) but much lower than the "peak" of 2000 (87 Mt). More seriously, the report stresses that there is no scope for expansion and that "despite local differences, the global potential of marine capture fisheries has been fully exploited, impose to restore depleted stocks and prevent the decline of those who are exploited to the maximum, or almost to the maximum, of their potential. "
In fact, since 1975, the fishery has undergone a reversal of the status of large fish species: "The proportion of stocks with potential for expansion has declined steadily" (about 24% of the total), while overexploited or depleted stocks have gone from about 10% in years 1970 to 24% in 2003. Of the ten most caught species, seven are considered to be fully exploited or overexploited: Peruvian anchovies, Chilean horse mackerel, Alaskan site, Japanese anchovy, blue whiting, capelin, Atlantic herring.
protected area network
The situation varies according to the fishing area. The Pacific is less affected than the Atlantic or the Mediterranean, which are, for the main species, fully exploited or overexploited. But this does not change the overall conclusion of the FAO report. In twelve of the 16 cut-off regions selected by the international organization, "the maximum fishing potential has been reached and more cautious and restrictive management is required".
Climate factors should not change the situation. We know that they can lead to sudden variations - in one direction or another - in some very important stocks, notably anchovy and sardines. However, in the event of over-exploitation, and therefore of fragile stocks, "the effects of climate on fisheries are exacerbated, as fish populations and the activities that depend on them become more vulnerable to the natural dynamics of the environment."
A particular concern is the deep-sea fish, whose exploitation has increased significantly the last ten years, while the knowledge of the biology of stocks available and the middle of diversity are still very patchy.
Orange roughy, oreos, alfonsino red, brominated and cusk, Antarctic toothfish and other moridées cod are thus all the more threatened they are caught in the open sea, where no legal regime can not supervise their operations.
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 Congress for parks (WPC), held in Durban in July 2003, recommended the establishment, by 2012, a global network of marine protected areas, restricting or prohibiting fishing locally and aggressive environmental activities. Their recommendation: do these areas cover a total 20 30% to% in sea surface warming. Either to 40 60 times the current network of marine protected areas.
"Guardians of the Seas"
Is this goal realistic from an economic perspective? how much would cost the establishment and maintenance of such a network?
In a recent study (PNAS June of 29 2004), an English team led by Andrew Balmford, researcher at the Department of Zoology at Cambridge University, attempted to estimate the cost of the establishment of global networks of areas protected extent and variables.
From the analysis of current marine protected areas, researchers first identified the main factors governing the cost of protection per unit area protected, taking account of its distance from the coast and index local economic development. Over this area is small, close to the coast and dependent on a rich country, and the cost of protection per square kilometer is high.
The researchers also estimated the costs of protecting 20 30% to area% of the world's seas in favorable and realistic conditions coalescence of protected areas. Result: 5,4 7 to billions of dollars per year are significantly lower than in 15 30 billion dollars used annually to subsidize fishing. And protection of 20 30% to area% of the world's seas should create 830 000 to 1,1 million full-time jobs.
A million "sea guards" face three to four million fishermen threatened if 30% on the surface of the oceans are prohibited from fishing. "It must be borne in mind that, without protection measures, the vast majority of the current 12 to 15 million fishermen will be deprived of work in the next decade," says Andrew Balmford.
These results show that the preservation of marine ecosystems and societies that exploit requires the establishment of protected areas not prohibited access, allowing the development of sustainable activities at sea, such as ecotourism and maintenance of the coast. Such alternative economic activities would allow a conversion of a good fraction of the fishermen of all countries.
The limit of 1 000 meters in the Mediterranean
Fishing in deep water beyond 1 000 meters should not be developed in the Mediterranean, under a decision adopted late February in Rome by the General Fisheries Commission for the Mediterranean (GFCM), an intergovernmental body. This decision, which should take effect in four months if the members have raised no objection is based on a study of biodiversity and fisheries conducted by the World Conservation Union (IUCN) and the World Wildlife Fund nature (WWF), which welcomed this progress.
"This is an important measure, the first in the world in this genre. This is a significant step towards sustainable fisheries in the Mediterranean, "says François Simard, coordinator of the IUCN World Marine Program. The exclusion of bottom trawling beyond 1 000 meters should in particular protect shrimp juveniles that find their nurseries there. For IUCN, this is a precautionary measure in accordance with the Convention on Biological Diversity.