The LME Concept

LMEs are described as relatively large bodies of water (200,000 sq. km) with distinctive bathymetry, hydrography, productivity and trophically dependent populations. Sixty-four LMEs have been classified around the margins of the Atlantic, Pacific and Indian Oceans. The LMEs produce 95 percent of the annual global fisheries biomass yields.

The Global Environmental Facility (GEF) strongly endorses the strategy of country-driven LME management. Through its International Waters Programme the GEF promotes the incorporation of an interdisciplinary approach, along with a development component to improve the management of marine resources.
GEF places priority on the development of a Strategic Action Programme that addresses changing sectoral policies and activities responsible for the root causes of transboundary environmental concerns.

One of the main focal areas for GEF funding is to mitigate factors that cause stress to the ecosystem and to promote priority actions for improving environmental quality and the sustainable development of resources within LMEs important to the economic growth and food security of developing countries.
Open ocean and coastal LME projects that have received substantial GEF support in development and implementation are the Benguela Current, Guinea Current, Yellow Sea, Agulhas-Somali Current, South China Sea, Canary Current, Humboldt Current and the Bay of Bengal.


The LME approach

In June 1992, a follow-on action to the United Nations Conference on Environment and Development (UNCED) declaration was adopted by the majority of coastal nations. These were:

  • prevent, reduce and control degradation of the marine environment so as to maintain and improve its life–support and productive capacities;
  • develop and increase the potential of marine living resources to meet human nutritional needs as well as social, economic and development goals; and
  • promote the integrated management and sustainable development of coastal areas and the marine environment.

In the immediate years following the United Nations Conference, increasing international concern was expressed over the deteriorating condition of the world's coastal ecosystems and living marine resources.

Within the near shore areas and extending seaward around the margins of land masses, it was noted that coastal ecosystems are being subjected to increasing stress from toxic effluents, over fishing, habitat degradation, excessive nutrient loading, harmful algal blooms, emergent diseases, fallout from aerosol contaminants and episodic losses of living marine resources from pollution effects and over exploitation.

To achieve the UNCED objectives, an ecological framework of management was proposed and adopted. This was the Large Marine Ecosystem (LME) concept.

An essential component of the LME approach is the inclusion of a scientifically based strategy to monitor and assess the changing states and health of the ecosystems by tracking key biological and environmental parameters. An assessment of the state of a LME is usually based on the following criteria: ecosystem productivity, fish and fisheries, pollution, socio-economic conditions and governance protocols.

The LME management approach includes regulatory, institutional and decision-making aspects, as well as scientific information on conditions, contaminants and resources at risk within the geographic extent of the ecosystem.


Changing conditions in the LMEs of the world

A United Nations report has found that 61 of the world's 64 large marine ecosystems show a significant increase in sea surface temperatures in the last 25 years, contributing to decreasing fisheries catches in some areas and increasing catches in others.

Fisheries harvests in several northern Atlantic LMEs, including the Norwegian Sea, the Faroe Plateau and the Iceland Shelf, are increasing due to the increase in zoo plankton, a vital fish food, brought about by the warming waters. However, climate warming is contributing to decreasing fisheries harvests in several European LMEs, including the North Sea, the Celtic Biscay Shelf and the Iberian Coastal LMEs.

The report documents the most rapid warming in the Northeast Atlantic and Mediterranean Region (Baltic Sea, North Sea and Black Sea LMEs), in the Northwest Pacific off East Asia (East China Sea, and Sea of Japan/East Sea LMEs), and in the Northwest Atlantic (Newfoundland Labrador Shelf LME). The notable exceptions to the warming are in the California Current LME and Humboldt Current LME (off the coasts of Chile and Peru). Both are in upwelling areas of nutrient-rich cool water in the Eastern Pacific Ocean.

"The large majority of these LMEs are shared by two or more countries, underscoring the need for regional cooperation to advance sustainable management," said Dr Kenneth Sherman, expert on Large Marine Ecosystems. "The added stress of climate warming makes it that much more important that nations cooperate to sustainably manage Large Marine Ecosystems, the areas where most marine fisheries are produced and caught."

According to the report, 70 percent of global fish stocks within LMEs are over exploited, reducing the availability of fish for food, which is especially critical in LMEs off the coasts of Africa, Asia and Latin America, where fish is a major protein source.

The UN report also said that an unprecedented volume of nitrogen effluent running into coastal waters is causing a greater frequency and extent of harmful algal blooms, oxygen depletion events and dead zones. During the algal blooms, small plankton consume excessive amounts of available dissolved oxygen, sink to the bottom and deprive fish and shellfish of the oxygen they need to survive.

The Global Environment Facility (GEF) has partnered with national and international agencies to assist developing coastal countries in their efforts to reduce coastal pollution, restore damaged habitats, and recover depleted fisheries. Several LME projects funded by the GEF are showing success in reducing coastal pollution, restoring damaged habitats, and recovering depleted fisheries.
The UNEP Large Marine Ecosystem Report – A Perspective on Changing Conditions in LMEs of the World's Regional Seas (2008) is available at www.lme.noaa.gov.