Threats to Mangroves
Unfortunately, to most people a mangrove looks like a muddy, smelly swamp that couldn't possibly be home to such a wealth of wildlife, so for decades mangroves have been cleared for a multitude of different reasons.
According to an FAO report in 2005 global mangrove coverage has fallen from 18.8 million hectares in 1980 to 15.2 million by the end of 2000 corresponding to approximately 20% of the global mangrove area in 1980 with Asia suffering the largest regional net loss.
Although the rate of deforestation has slowed, it is still occurring at an alarming rate of approximately 1% per year through clearing for:
- shrimp farms and aquaculture
- property development
- tourist facilities
- oil exploration and extraction
- dumping grounds
- and quite often just to create a 'nicer view'
By far the most voracious threat is the 'boom and bust' shrimp farming industry. It has been reported that as much as 50% of the mangrove loss so far is due to this unsustainable business.
Commercial Shrimp Farming
Commercial shrimp farming began in the '70s to match market demands from the U.S, Japan and Western Europe.
In this time just over one million hectares of important wetlands, including mangroves, have been cleared for use by this industry and now at least 250,000 hectares lie abandoned and ecologically dead due to the disease and pollution these farms cause to the area.
Shrimp usually need four years to reach a harvestable size, so in order to make their business profitable, companies use chemicals to increase shrimp growth to attain a harvestable size within 12-18 months.
The ponds used are never cleaned, leaving the shrimp to exist in their own excrement and waste needing more chemicals and antibiotics to be added to keep them disease free.
All these chemicals are released into the ocean, and without the mangroves to filter them, overflows cause mass pollution and fish kills.
But these businesses are not only bad for wildlife. The human cost is huge; for it is the few that benefit from the short term profits while the local fisherfolk, once dependant on healthy, coastal ecosystems, are displaced and poverty stricken.