Humans are fascinated with the oceans and their respective coastlines. It is no surprise that records dating back over 2000 year show study of mangroves. The majority of this early study probably focuses on the use of these extraordinary trees and shrubs. Observations by early explorers and settlers not only focus on the trees themselves, but of the associated species of wildlife that inhabit these productive communities.

Bark is used as a source of tannins and dyes. Mangroves produce durable and water resistant wood used in houses, boats, pilings, fence posts and furniture. Dense Black mangrove and Buttonwood wood is used in charcoal production. The fruits may be eaten. Leaves are used as source of tea, medicine, and livestock feed. The flowers are used in the honey industry. Leaves can also be dried and smoked as a substitute for tobacco. Other than mangrove honey production most direct uses are destructive.

In the Florida and the Keys, three species of mangroves dominate the marine influenced wetland areas: Red Mangrove (Rhizophora mangle); Black Mangrove (Avicennia germinans); White Mangrove (Luguncularia racemosa).

The term mangrove does not refer to a specific taxonomic group of species. One description implies all halophytic (salt tolerant) species of tropical trees and shrubs representing approximately 12 families and over 50 species. All are not necessarily related, but all are adapted to living in loose wet soil, saline habitat, and periodic tidal submergence. In addition, all possess differing degrees of vivipary (live birth) with propagule (seedling) formation. In mangroves this is accomplished with seed germination while still attached to the parent tree.

Mangroves dominate 75% of the tropical coastlines between latitudes 25 degrees N -25 degrees S or higher latitudes bathed by equatorial originating water masses. Along the coast of Florida, the close proximity of the Gulf Stream and the Florida Current aid in development of mangrove communities. With only three species of mangrove present, Florida's species composition seems somewhat low compared to areas of the Indo-West Pacific with over 30 species reported. However, extreme conditions for growth should be expected with most areas in Florida north of 250 N. Red and White mangroves are found as far north as Cedar Key in the Gulf of Mexico and Ponce de Leon inlet on the east coast of Florida. Black mangroves are found farther north to Jacksonville on the east coast and along the panhandle in the Gulf due to their ability to grow from the undestroyed roots after a freeze.

Mangroves are tropical species which do not develop well where the average temperature is less than 660 F (l90 C). High temperatures above l070 F (420 C) are also thought to be limiting. Normally, temperature fluctuations greater than 500 F (l00 C) are not tolerated well. In Florida, the impact of low temperatures on mangroves results in decreases in structural complexity of the community. When compared to mangrove communities of areas with more favorable temperature, Florida’s mangrove communities show decreased tree height, decreased leaf area, and increased tree density.

All three species trap, hold, and stabilize intertidal sediments. With these facts in mind, early hypotheses are misconceptions that mangroves are “land builders”. The role in land building is more passive than active by sediment trapping and litter production. Probably, a better term for mangrove is a “land stabilizer”. Black mangroves may be the best land stabilizer due to easier seedling transport, quick aerial root production, underground root systems increase sediment holding capabilities, higher tolerance to cold temperatures, better ability to inhabit "artificial" sites (dredge, fill, etc.). Red mangroves are second best and whites are the worst. During extreme storms and hurricanes mangrove forests protect landward coastal area by mitigating damage from waves, currents, and winds.

A variety of organisms utilize mangrove habitats. A myriad of marine species is found as inhabitants of the underwater prop root complex and tidal channels. All fish and shellfish caught commercially, and by recreational means utilize mangrove habitat at some point in their life cycle. In addition to the marine organisms, both terrestrial organisms and birds utilize the forest floor, root complex and the canopy. Florida mangrove communities are also known to provide habitat for number of threatened and endangered species. Among the endangered species are the American Crocodile, Hawksbill and Atlantic Ridley Turtles, Bald Eagle, American Peregrine Falcon, Key Deer, Barbados Yellow Warbler, Atlantic Saltmarsh Snake. Threatened species are the American Alligator, Green and Loggerhead Turtles.

Acreage estimates of 430,000-540.00 acres (l981) of mangrove communities vary widely due to inadequate groundtruthing. Ninety percent of these communities are in Lee, Collier, Dade, and Monroe counties of south Florida. Approximately 280,000 of these acres are held by Federal, State, County governments, or non-profit organizations. The majority of these acres are within the Everglades National Park. The rest account for the undeveloped shoreline of the counties listed above.

Due to increased water turbidity in mangrove waters, roots are extremely susceptible to clogging, as well as prolonged flooding and damage due to boring organisms. Other natural deleterious effects resulting from organisms are gall production by wasps and parasitic yellow lichens. Extreme hurricanes extensively damage mangrove forests.

Natural destruction is relatively low compared to human impact of these communities. A variety of deleterious stress include dredging, filling and diking; oil spills; herbicide and human waste runoff. Estimates of a 5% loss of acreage statewide as compared to acreage estimates of the l9th century. However, an estimate in certain locales of wetland loss is up to 44%. However, urban destruction usually results in a total loss of habitat. As population growth continues, the pressures to alter these communities continue. Therefore, due to the importance and finite nature of these natural habitats, preservation is in our best interest.