At present, mangrove forests cover an area of 181,000 km2, distributed in over 100 countries, but during the past 50 years, over 50% have been lost. Some direct activities are destroying mangroves or are degrading them, including substitution by other activities such as shrimp farming and agriculture, forestry, salt extraction, urban development, tourist development and infrastructure. Furthermore, other impacts include deviation of river water and contamination, caused by heavy metals, oil spills, pesticides and other products.
The establishment of shrimp farms has been the main cause of mangrove loss in many countries over the past 30 years. In Vietnam, a total of 102,000 hectares were converted to aquaculture between 1983 and 1987; in Honduras between 1986 and 1994, over 12,000 hectares were destroyed for the construction of shrimp ponds; in Ecuador over 180,000 hectares of shrimp ponds were built in mangrove areas; in Thailand, between 1961 and 1993, over 80,000 hectares of mangroves were destroyed to turn them into shrimp breeding ponds.
This loss of mangroves in the tropics has been facilitated on a major scale by international financial support, mainly provided by the World Bank and the Asian Development Bank. The International Financial Corporation approved, between 1997 and 2000, loans amounting to 82 million dollars for the development of aquaculture in Latin America. The “beneficiary” countries have been Belize, Mexico, Honduras, Ecuador and Peru.
One of the forces behind the mass loss of mangroves over the last decade has been the inability of economists to recognise the value of natural products and ecological services produced by this ecosystem. This has led to mangroves being considered as lands with no use, with no value and wasted and therefore subject to conversion to uses such as shrimp farming, generating products with a market value.
However, mangroves generate a wide range of natural resources and ecosystem services. Some of these services, such as protection against hurricanes and floods, reduction of erosion and maintenance of biodiversity, are key functions that sustain economic activities in tropical coastal areas. Forest products from mangroves, such as building materials, charcoal, tanin, drugs and honey are vital to subsistence and provide a commercial base for local and national economies. Coastal subsistence economies in many developing countries are strongly dependent on fishing from mangroves.
It has been established that each hectare of mangrove generates between 1,100-11,800 kgs of fisheries catches. This productivity is much higher than the 10-370 kg/ha/year found for coral reefs. In developing countries, the annual value of the fish market depending on mangroves varies between US$900 and US$12.400 per hectare of mangrove. It should be stressed that this value is based on a single good from the mangrove, that is to say, only fisheries. Additional efforts to estimate the economic value of forest resources and ecological services generated by mangroves, will demonstrate the significant value of this ecosystem and its support to subsistence and to local and national economies.
While this recognition regarding the value of mangroves and support by the authorities for their conservation is yet to be achieved, over the past few years, coastal communities have gone through one of the most critical times in all their history. Following decades or centuries of use of these ecosystems without any major conflicts, they are now facing the daily fact of seeing how two, twenty or sixty bulldozers, arrive on a “bad day” to destroy, in less than two weeks, what had been their subsistence and economy for generations. At the end of two months, all that is left are memories and an enormous amount of shrimp-breeding ponds.
Mangroves are being lost for ever and with them, the economies of hundreds of coastal communities, mainly coastal artisan fishers. This destruction is being extended day by day through all countries in the world having tropical coasts. In Latin America, from Mexico to Peru and Brazil, the shrimp industry does not stop. The efforts by coastal communities to defend their mangroves have cost the life of various artisan fishers in Mexico, Guatemala and Honduras. Presently grassroot movements are growing and to co-ordinate and detain the scourge, the “Mangrove Network” has been set up, aimed at providing all the coastal communities with a mechanism to co-ordinate efforts. During its first assembly held in September this year, the Mangrove Network achieved membership from organisations in ten countries of Latin America, with the objective of struggling with a single voice, Mangroves are life, long live mangroves. Justice for mangroves.
By: Elmer López Rodríguez, Greenpeace.