Mangrove Forests

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The meandering coasts of Sarasota County really are just that... meandering or walking. Mangrove Forests like these are made up "walking trees", so called because of the way they extend their roots from the base trunk and expand their footprint. It appears that the tree and the land it helps to foster grow, move and travel. Florida's mangrove forests are the most extensive in the United States and covers more than 400,000 acres. Mangroves are also found in the stares of Mississippi, Alabama, and Louisiana.

Mangrove forests in the tropics and subtropics are identifiable by their dense tangle of prop roots that help the trees handle the rise and fall of the tides. This dense tangle of roots acts as a net, holding and stabilizing shorelines. In addition, these roots provide shelter to the majority of all recreationally and commercially important fish species in Florida.

Their unique structure makes them able to withstand major storm forces like those from hurricanes. Mangroves are a keystone species providing essential services that act as the base for the entire estuarine community. Occasionally referred to as the "kidneys of the coast," mangroves are magnificent filters and maintain necessary water clarity for offshore corals and near shore seagrasses.

In fact, mangroves are so essential to the coastal ecosystem that laws have been passed to protect these trees. The 1996 Mangrove Trimming and Preservation Act prohibits trimming or alteration of mangroves on publicly owned lands and sets specific limits for trimming or removal of mangroves on private property.

There are three native mangrove trees found in Florida: red mangrove, black mangrove, and white mangrove. The Red Mangroves (Rhizophora mangle) are the trees people generally associate with "walking trees", with their reaching prop roots and long, dangling, pencil-like propagules and their horizontal growth habit. They are generally found in standing water. These trees reach between 20 and 75 feet tall. The national champion red mangrove is in Lee County Florida, documented at 64 feet tall.

Black Mangroves (Avicennia germinans), an evergreen tree, generally grows further inland than reds, where the roots are still inundated during high tide. and reach heights of 40 to 60 feet tall. They have a higher salt tolerance than the other two species, and have glands on their leaf surfaces that excrete excess salt. Historically, indigenous people gathered the leaves for this salt, and the wood was an important fuel source for smoking fish. Their bark was also used in the tanning process as a black dye for animal skins. Black mangrove flowers are a popular nectar source for honey bees, leading to the creation of "mangrove honey."

White Mangrove (Laguncularia racemosa) is more of an upland species, and generally found further inland along the coast where it is irregularly flooded in the intertidal zone. These trees reach 30 to 40 feet tall. White mangrove trees produce hard, strong wood that has historically been used for lumber. Most commonly these trees were used as a fuel source and for tanning leather.

Mangrove Forests are known as a nursery as they provide spawning and nursery territory for juvenile marine species including shrimp, crabs, and many sport and commercial fish species such as redfish, snook and tarpons. Branches of the mangroves act as bird rookeries and nesting areas for coastal wading birds including egrets, herons, cormorants and roseate spoonbills. In some areas, red mangrove roots are ideal for oysters, which can attach to the portion of the roots that hang into the water. Endangered species such as the smalltooth sawfish, manatee, hawksbill sea turtle, Key Deer and the Florida panther rely on this habitat during some stage of their life cycle.