Mangroves of the Sebastian Shoreline

Three mangroves grow on the Indian River Lagoon shore at Sebastian: the red, the black and the white, all listed for the Indian River-Malabar to Vero Beach Aquatic Preserve.

That state preserve covers the lagoon off Sebastian in Brevard and Indian River counties. FDEP gives it 28,000 acres and an establishment year of 1970, and it lists seagrasses alongside the three mangroves as the preserve's signature plants (Florida DEP).

Each species sits at its own height on the Sebastian shore. The red mangrove typically grows along the water edge and is known by tangled, reddish prop roots. The black mangrove occupies slightly higher ground and is identified by pneumatophores, finger-like projections that rise from the soil around the trunk. The white mangrove holds the highest ground and is easiest to identify by its leaves: elliptical, light yellow green, with two glands at the base of the blade (FDEP). FDEP adds that all three frequently grow intermixed.

Around Sebastian the mangroves form a fringe on the barrier island, the spoil islands and parts of the mainland shore, and several public sites put them in easy view.

The 1986 state management plan for the preserve described the pattern on this stretch of the lagoon: mangrove trees fringe the shoreline of the barrier island and, to a lesser extent, the mainland and perimeters of the spoil islands. Those spoil islands were created from dredge material during the construction of the Intracoastal Waterway (Florida DEP), and the U.S. Fish and Wildlife Service notes that many spoil and mangrove islands fall within the boundaries of Pelican Island National Wildlife Refuge.

On land, the refuge public use areas are on the Historic Jungle Trail, 3.3 miles south of Sebastian Inlet. The Centennial Trail address is 11455 Jungle Trail, Vero Beach, and the refuge is open sunrise to sunset every day (USFWS, Visit Us). Farther south in Indian River County, the FDEP Coastal Access Guide says the Lagoon Greenway traverses over 3 miles of coastal plain, maritime hammock and mangrove forest. Across the lagoon from Sebastian, Coconut Point at Sebastian Inlet State Park is the site of the newest planting, described below.

Mangroves grow well north of Sebastian: FDEP says they are common as far north as St. Augustine, and their range is set by freezes along with salinity, water temperature, tides and soil.

For trees on the Sebastian shore, the limit lies well to the north. FDEP notes that Florida's mangroves are tropical species, sensitive to subfreezing temperatures, and that salinity, water temperature, tidal fluctuations and soil also affect their growth and distribution. It states that mangroves are common as far north as St. Augustine on the Atlantic coast and that black mangroves can occur farther north in Florida than the other two species (FDEP). The UF/IFAS review of range expansion reports stands of black mangroves as far north as the St. Augustine inlet. It also notes that black mangroves largely do not tolerate frosts and freezes, although recent research found they recovered from exposure to temperatures as low as about 19 F for a short duration.

The shift is measurable up the coast from Sebastian. Aerial images from 1984 to 2011 show the Florida Atlantic coast gained more than 3,000 acres of mangroves; all of the increase occurred north of Palm Beach County, and the acreage between Cape Canaveral and St. Augustine doubled, much of it at the expense of salt marsh (FDEP). The lagoon at Sebastian sits south of that doubling zone, where the 1986 plan already recorded an established fringe.

Yes, within limits: a Sebastian owner may trim a riparian mangrove fringe without a permit when the trees are no taller than 10 feet and none is cut below 6 feet.

Section 403.9324 of the Florida Statutes makes the Mangrove Trimming and Preservation Act, and the rules of any local government holding delegated authority, the sole regulations in the state for trimming and altering mangroves. The homeowner exemption in section 403.9326 applies only if no herbicide or other chemical is used to remove foliage. This exemption applies to property with a shoreline of 150 feet or less; owners of a longer Sebastian shoreline may not trim more than 65 percent of the mangroves under it.

Taller trees along the Indian River Lagoon need a professional mangrove trimmer. Under the same statute a professional may work on mangroves up to 24 feet in pretrimmed height, again not below 6 feet, and trees 16 feet or taller are cut in stages. A professional trimming red mangroves for the first time under this exemption must notify the department in writing at least 10 days before starting (s. 403.9326). Work beyond the exemptions moves to a general permit under section 403.9327, which allows no more than 25 percent of the foliage to be removed annually.

Inside the aquatic preserve itself, the 1986 management plan set a stricter policy: prohibit the trimming or removal of mangroves and other natural shoreline vegetation within the preserve, except for legally authorized projects and local mangrove protection ordinances. A Sebastian owner whose fringe sits on sovereign submerged land in the preserve has reason to ask FDEP before cutting.

For Sebastian, the Florida Department of Environmental Protection handles mangrove trimming, because neither Indian River County nor the City of Sebastian holds a delegation.

The FDEP delegation list names seven local governments: Miami-Dade County (305-372-6575), Broward County (954-519-1483), Hillsborough County (813-627-2600), Pinellas County (727-453-3385), the Town of Jupiter Island (772-545-0150), the City of Sanibel (239-472-3700) and Sarasota County. Indian River County is absent, so state rules and the state agency apply on every Sebastian waterfront lot.

The FDEP Central District covers nine counties, including Brevard and Indian River, from its office at 3319 Maguire Boulevard, Suite 232, Orlando, telephone 407-897-4100. The district's primary functions include permitting and compliance, which makes it the first office to call before a Sebastian trimming job that may need a general permit. Last verified: October 14, 2026, on the Florida Department of Environmental Protection website.

Mangroves have been replanted at Pelican Island, on about 230 acres of lagoon shore from the San Sebastian River to Sebastian Inlet, and most recently at Coconut Point.

At Pelican Island the island measured 5.5 acres in 1903, began to shrink around 1943 and by 2000 was less than half its original size. A 2001 project installed a 165-foot oyster shell wave break and planted smooth cordgrass and mangroves along the island shore to encourage sediment accretion (USFWS, About Us). The same page now puts Pelican Island Proper at roughly 3 acres, a loss it attributes to years of boat-induced wave action and sea-level rise.

The NOAA Restoration Center records that the Marine Resources Council, with FDEP and volunteers, restored approximately 230 acres of shoreline through invasive species removal and native mangrove planting, starting in October 2002, at sites in the San Sebastian River State Buffer Preserve, Sebastian Inlet State Park and Pelican Island National Wildlife Refuge. Community volunteers planted 5,284 native mangroves along the shoreline of the Indian River Lagoon. The council still grows the trees locally: its October 25, 2025 Sebastian Mangrove Workshop focused on growing red mangroves at its Sebastian nursery for lagoon shoreline habitat (Environmental Learning Center).

On September 10, 2026, 22 reef arch structures were installed along approximately 200 feet of eroded shoreline at Coconut Point, on the south side of Sebastian Inlet State Park, with up to 90 mangrove plants to be installed in the coming weeks under a $95,000 state cost-share grant (Sebastian Inlet District). The district page was last updated September 18, 2026, and as of October 14, 2026 it had not reported the mangrove planting as finished, so the reef arches are the confirmed part of the project.

Along the Sebastian lagoon, mangroves serve as fish nurseries, bird rookeries and shoreline anchors.

FDEP describes mangroves as protected nursery areas for fishes, crustaceans and shellfish and as food for snook, snapper, tarpon, jack, sheepshead, red drum, oyster and shrimp; the aquatic preserve off Sebastian lists redfish, tarpon and snook among its fish (Florida DEP). Mangrove branches are rookeries for coastal birds such as brown pelicans and roseate spoonbills. Mangroves also help prevent erosion by stabilizing shorelines with their root systems and help maintain water clarity (FDEP). The Sebastian Inlet District describes living shorelines like the Coconut Point project as a resilient alternative to seawalls that absorbs wave energy.