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 Lakes, Estuaries
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Natural Areas Directory


ERM Directory


Florida's Mangroves: The Walking Trees


Mangroves serve very important functions in the ecology of South Florida. Mangroves have a high ecological role as nursery grounds and as a physical habitat for a wide variety of vertebrates and invertebrates. They recycle nutrients and the nutrient mass balance of estuarine ecosystems. Mangrove leaves, wood, roots, and detrital material provide essential food chain resources, and provide habitat for many wildlife including mammals, birds, reptiles, amphibians, and arthropods. Mangroves have a special ecological function for endangered species, threatened species, and species of special concern. They also serve as storm buffers; their roots stabilize shorelines and fine substrates, reducing potential turbidity and enhancing water clarity. One of the greatest values of mangroves swamps in Florida is their aesthetic appeal.

Four major factors limit the distribution of mangroves: climate, salt water, tidal fluctuation and soil type. Mangroves are found in tropical and subtropical estuarine habitats. They rarely tolerate temperatures below freezing; therefore occur in regions where the annual average temperature is above 19 C (66 F). Mangroves can live in salt water and are able to keep the salt content lower than the salt content in the soil. They accomplish this with several methods: secreting salt through salt glands; secreting salt through their roots; thick leaves with a waxy covering; facultative halophytes. Water fluctuations are important to mangrove forest development because the tidal action carries mangrove propagules into upper portion of the estuary.

Rhizophora mangle

Red Mangrove
The red mangrove is often found seaward of the other species and grows in frequently flooded areas. This species belongs to the family Rhizophoraceae and is very easy to identify. Red mangroves have characteristic aerial roots, which originate downward from the trunk and lower branches. These roots are an adaption to saltwater environment. The tree can take in oxygen directly from the surrounding air. The roots also provide the tree additional support to remain upright in the muddy substrate. The leaves are shiny, thick, leathery and dark green. Red mangrove fruits germinate on the parent tree to form long, pencil shaped propagules which act as seedlings. These seedlings are denominated viviparous. Flowering in spring and summer, although it can occur throughout the year. Although usually shorter than other types, the red mangrove tree may reach up to 50 feet in height.

Avicennia germinans
Black Mangrove
Black mangroves are often found in close association with red mangroves and seem to grow in the most salt-rich soils. The tree belongs to the family Avicenniaceae. On the ground around the black mangroves one can find numerous pneumatophores which extend upwards above the mud from the submerged root system. Pneumatophores are essentially the erect lateral branches of an otherwise horizontal root system. They serve the same aerating purpose as the prop roots of the red mangrove. The leaves of the black mangrove are narrow and oblong, dark green above and silver-green underneath. The black mangrove can grow as tall as 60 feet.

Laguncularia racemosa
White Mangrove
White mangroves usually grow on higher land, landward of red and black mangroves. They are often found in association with black mangroves. The white mangrove belongs to the family Combretaceae. Contrary to the other two species, the white mangrove does not develop prop roots or pneumatophores. The most identifyable characteristic of the white magrove are the leaves. The leaves are thicker and more oval than those of the red and black mangrove, and they are uniform pale green on both surfaces. On either side of the stem one can see two small glands on each leaf. The white mangrove grows as a tree or shrub and can reach a height of 50 meters or more.

For more information on mangroves, click here. [External Link]


Current Highlights and Upcoming Events

  • Hungryland Slough Natural Area - REOPENED
  • Lake Worth Lagoon Initiative Grant Program
    Now accepting applications for FY 2017. Deadline to submit is August 15, 2016. [LINK]
  • Pawpaw Preserve - UPDATE
    The Pawpaw Preserve Natural Area draft management plan is now available for public review. Public comments can be emailed to,or can be provided at the May 26, 2016 Public Hearing and Open House. Click on the link for time and location. [LINK]
  • Adventure Awaits - Sunrise Hike, May 7th 6:30am
    Join us for a guided hike through Cypress Creek Natural Area in Jupiter. For more details and to reserve your spot, click on the link to the event page. [EVENT PAGE]
  • Adventure Awaits - Firewalk, The Spark of Life, May 24th 5:30pm
    Join us at Sweetbay Natural Area in Palm Beach Gardens for this guided hike. For more details and to reserve your spot, visit the event page. [EVENT PAGE]
  • Adventure Awaits - Namaste, Yoga in the Natural Areas, May 25th 6:30pm
    Join us at Yamato Scrub Natural Area in Boca Raton for this unique experience. For more details and to reserve your spot, visit the event page. [EVENT PAGE]
  • Lake Worth Lagoon Fishing Challenge, June 1st - 30th
    Interested in helping collect valuable fisheries information while getting a chance to win a prize? If so, you'll want to participate in this free fishing event. Visit the web page for details. [LINK]
  • Running Wild, June 4th 7:00am
    Run with ERM at Loxahatchee Slough Natural Area will cover approximately 10 miles and take participants through a variety of habitats on a combination of hardened and primitive trails. For more details and to reserve your spot, visit the event page. [EVENT PAGE]
  • Adventure Awaits - Sunset Photography Workshop, June 10th 6:00pm
    Take part in a guided photography tour of Winding Waters Natural Area in West Palm Beach. For more details and to reserve your spot, visit the event page. [EVENT PAGE]
  • Adventure Awaits - Sunset Paddle, June 15th 5:30pm
    Come paddle with ERM staff to Fullerton Island in Jupiter as the sun sets over this recently restored 12 acre maritime hammock island with newly created seagrass and mangrove habitat. For more details and to reserve your spot, visit the event page. [EVENT PAGE]
  • Adventure Awaits - Growing Up Wild, Connecting Kids to Nature, June 18th 9:00am
    ERM staff will lead you and your child on a guided walk through the woods at Royal Palm Beach Pines Natural Area highlighting points of interest associated with "Birds in Your Backyard" followed by an arts and crafts project each child can take home. For more details and to reserve your spot, visit the event page. [EVENT PAGE]
  • Adventure Awaits - Bike and Hike, June 25th 8:00am
    Discover the trails of Loxahatchee Slough with ERM staff during this unique tour that incorporates cycling and hiking. For more details and to reserve your spot, visit the event page. [EVENT PAGE]
  • Environmental Times Newsletter
    Read the latest edition Spring 2016 for highlights on artificial reefs, climate change, LagoonFest and more. [LINK]
  • Volunteer Accomplishments in 2015
    See what ERM's volunteers were up to in 2015. [PDF]
  • Mosquito Control Update - Zika Virus
    While ERM's Mosquito Control Division is hard at work taking proactive steps to reducing mosquito popluations learn how you can protect yourself and reduce your exposure to mosquitoe-borne diseases. [PDF]
  • Scavenger Hunts
    Are available at several natural areas for youngsters to complete to recieve their Natural Area Youth Explorer certificate. [PDF]
  • ERM's Status Reports
    Stay up to date on our projects with these monthly publications. [LINK]