Restoring our Mangrove Forests

What can we do?

The natural ecological and economic benefits lost with mangrove loss are significant and non-retrievable. However, there are simple approaches and understandable by most people that can help protect and manage our mangroves. There are four management options that have been identified for mangroves.

Establishing and managing mangrove nurseries would help ensure the availability of planting materials, as well as production of high quality seedlings.

By establishing and maintaining mangrove plantations aside from natural mangrove forests, the benefits of mangroves including protection from coastlines, source of food and fisheries are maximized.

Community-based forest management agreement is a production sharing agreement entered into between a community and the government to develop, utilize, manage and conserve a specific portion of the forest land, and in this case mangrove forests. Rather than just cutting entire mangrove trees, residents plant and maintain mangrove trees to promote faster growth and better quality wood products.

Aqua-silviculture, which is the conversion of fishpond area into a site where mangroves can grow and fish can thrive is a suggested fishpond restoration strategy.

Status and Threats to our Mangroves

STATUS OF MANGROVES

Forested mangrove area has decreased greatly in the Philippines from an estimated coverage of 450,000 hectares in 1918 to less than 120,000 hectares in the late 1990’s. The most rapid decrease in mangrove coverage happened during the 1960’s and 70’s when aquaculture was promoted by the national government.

THREATS TO OUR MANGROVES

The culprits in the decline of our mangroves are many, but the primary one is conversion to aquaculture ponds and conversion to urban land reclamation and other land uses. If this trend continues, there will be virtually no mangroves left in the Philippines after another 50 years.

Aside from natural or indirect threats to mangroves, human interventions, mainly fishpond conversion caused the decline of mangrove forests in the country. Now, mangrove forests remaining along the Philippine coasts are of much lower quality than those found in the early centuries. Other causes of mangrove decline include reclamation of mangrove areas for various developments such as wharfs, piers, airports, housing and industrial zones; Pollution and siltation; Dikes and structures obstructing waterways and tidal inundation that disturbs the tidal flow; Overexploitation and utilization, including harvesting of mangrove trees for charcoal, timber and other uses; and disturbance due to gleaning, fish landing.

Importance of Mangrove Ecosystems

MANGROVE ECOSYSTEM

The basic coastal ecosystems are critically linked in such a way that there is a mutual exchange of benefits between and among these ecosystems. For instance, the algae and bacteria growing in the healthy mangrove forest and seagrass beds are vital to the nutrients needed by the coral reef animals. Moreover, mangrove and seagrass habitats serve as nursery grounds and feeding areas for coral reef and small pelagic fish.

The disruption of one ecosystem affects the whole coastal environment, which as a consequence leads to loss of life and property.

Mangroves provide numerous products and benefits. Mangroves provide good nurseries for the young animals because the extensive rooting structures serve as hiding places for young fish, shrimp, crabs and other animals in the sea. This protection, along with the abundant food supply that comes from mangrove leaves, makes mangrove areas very good nurseries. For every hectare of mangrove cut down, a corresponding reduction in fish catch is estimated at 1.08 tons per hectare per year.

One great benefit of mangroves is the nutrients produced from decomposing leaf litter. Known as “detritus” these small pieces, almost invisible to the naked eye is broken down by bacteria, fungi and micro-organisms that serves as nutritious food for shellfish, shrimps, and fish. A healthy mangrove can contribute about 3.65 tons of litter per hectare per year that helps maintain the delicate food chain or food web of the coastal ecosystem.

The crown and stem of mangroves serve as physical barriers. Their specialized roots trap and hold sediments and siltation from the uplands. Further, mangroves promote clear water and the growth of corals and seagrasses.

Mangroves provide shelter for local and migratory birds, and other interesting animals making mangrove forests attractive ecological destinations and field laboratories for biology and ecology students, researchers, birdwatchers and tourist. The Olango Island Wildlife Sanctuary is one example in Cebu.

Mangroves are good source of wood and timber and nipa shingles for housing materials, firewood, charcoal. Some mangrove species have medicinal value; others provide tannin for leather preservation and dyes for cloth. The sap are even used in some areas for food, including fermented drinks.

Aqua-culture and commercial fisheries depend on mangroves, for young and mature fish species. While crabs, fish and prawns are also harvested for human consumption.