Why planting mangroves is good news for whale sharks

ATTRACTION: Tourists come to see the whale sharks. Picture: Jurgen Freund

10,000 mangroves planted by volunteers in Philippines

January 2012: With the help of almost 300 volunteers, 10,000 mangroves were recently planted in Donsol in the Philippines. Mangroves are vital for Donsol's wildlife - providing homes for fireflies, indicators of healthy ecosystems, and fuelling the growth of plankton, which in turn attract whale sharks.

‘Whale sharks congregate in Donsol because of all the plankton,' explains WWF-Philippines Project manager Raul Burce. ‘Plankton consume nutrients discharged by Donsol's still-healthy rivers, one of the few habitats where fireflies still thrive. Remove mangroves and the fireflies shall be driven off.

If whale sharks disappear it could be catastrophic
'Without the healthy rivers needed by fireflies, plankton populations cannot bloom - and the whale sharks will migrate elsewhere. If one component crashes, the others follow suit. This could be catastrophic for the people of Donsol.'

Wildlife tourism has transformed Donsol - a total of 24,191 local and foreign visitors swam with the gentle giants from December 2010 to June 2011. Donsol's Municipal Tourism Office estimated that the 2010 season alone generated over $2.3million from transportation, food, lodging, registration fees plus whale shark, mangrove and firefly tours. 

Mangroves generate 500kg seafood per hectare each year
Now the World Wide Fund for Nature (WWF-Philippines) has spearheaded a vigorous reforestation drive to plant 10,000 mangrove seedlings in Donsol's Barangay Sibago last month.

Known in Tagalog as bakawan, mangroves constitute one of the most productive of marine habitats - able to generate 500kg of seafood per hectare annually.

VITAL WORK: Volunteers plant mangroves in the Philippines. Picture: Raul Burce

They absorb significant amounts of carbon dioxide- the major culprit for climate change. The thick onshore hedges protect coastal communities from violent gale winds and waves caused by typhoons. Labyrinthine roots shelter fish and invertebrates while stabilising sediments and absorbing heavy trace metals to minimize coastal erosion and prevent inland salt-water contamination. Even fallen leaves are used by some animals for food and shelter.

Nearly three-quarters of original mangroves have been destroyed
As well as threatening the tourist industry, loss of mangrove forests expose coastal communities to increased flooding, faster beach erosion, saline intrusion and severe damage from intensifying storms.

Up to 75 per cent of the original cover has been lost as a result of programmes to develop seemingly-idle mangrove forests into fish and shrimp ponds for profit. Mangrove planting drives have been attempting to remedy this.

WWF-Philippines vice-chairman and chief exectuive Jose Ma. Lorenzo Tan said: ‘The key here is balance. Without it, the productivity of our natural systems will crash. Strike a balance between conservation and development and we can ensure sustainability.'