When Hurricane Charley churned ashore in Southwest Florida last summer, it clear-cut vast stretches of the mangrove forest in J.N. Ding Darling National Wildlife Refuge, on Sanibel Island.
Mangroves play the most vital role in tropical ecosystems, and an estimated 85 percent of mangrove forests in Florida have been destroyed by humans. Fallen, decaying mangrove leaves provide the nutrients that feed an estuary’s most basic organisms. The roots provide an essential sanctuary for most of Florida’s inshore and offshore gamefish and water-filtering shellfish, as well as nesting habitat for many species of birds. Though damaged mangrove plants can recover over time from hurricane winds, damage to the Refuge’s mangrove forest was so severe in places that a jump-start was needed.
That jump-start is being provided by a volunteer group headed by Capt. Pete Greenan and local members of the Federation of Fly Fishers (FFF), Boy Scout troops, members of the Sanibel Fly Fishers and Mangrove Coast Fly Fishers and others, working in collaboration with the U.S. Fish and Wildlife Service.
According to Refuge manager Rob Jess, the consequences of mangrove damage are already mounting. Limbs and trunks of uprooted trees have clogged parts of the impoundment, so beginning in April, volunteers cleared a vital tidal creek to restore tidal flow into impounded areas for the regeneration of mangroves, and to encourage the return of migratory birds. Work is also under way to clear debris from around young mangroves, to allow water to flow freely and encourage the plants to grow at an accelerated pace.
Charley crashed into OIA last year on August 13th.
A call to preserve mangrove forests
Another environmental service provided by the forests is that of soil retention. Mangrove forests stabilize shorelines by reducing the severity of waves, while their roots hold soil in place (Ibid 134). According to a study by Grasso and Schaeffer-Novelli, Òretaining sediment in headwater wetlands will lengthen the lifespan of downstream reservoirs and channels, and reduce the need for costly removal of accumulated sediment.Ó The function of stabilizing shorelines is closely related to a third environmental service, which is that of reducing the severity of tropical storms. Mangrove forests act as natural basins and reservoirs, and through their ability to store and release runoff, they can help to alleviate the damage caused by flooding, at a cost far less than creating man-made dams and reservoirs.