With more than 1,300 miles of coastline, Florida’s habitats include many communities adapted to life along the sea, where wind and salt spray shape the environment. These brief descriptions of commonly-encountered natural communities include where you can find some of the best examples of these natural habitats along Florida’s trails.
Coastal dunes are created by the wind. Tall deep-rooted grasses, providing stripes of shade for the burrows of crabs and mice, anchor the sparkling dunes.
Coastal grasslands occur between the dunes and the maritime forest as grasses get established in the sand, the first step in “settling down” the dunes from drifting away as the wind pushes them around. Panicumand Spartinagrasses are typical ground cover, with scattered wildflowers.
Once vegetation larger than grasses gets a foothold in the dunes, it stabilizes them even more and prevents any ongoing movement of the dunes. These shrub-covered dunes – frequently covered in a silvery-tinged variety of saw palmetto as well – are part of the coastal strand.
Mainly found along the Gulf Coast in Northwest Florida, this salt-tolerant scrub community also forms atop coastal dunes. It tends to be very picturesque, with colorful wildflowers like Gulf Coast lupine and day-flower as well as prominent Florida rosemary bushes.
Coastal Dune Lakes
Only found in Northwest Florida and centered on Walton County’s coastline, coastal dune lakes are rare globally. These freshwater lakes adjoin the Gulf of Mexico and exchange their waters with the sea when water levels grow high enough for an “outfall” to occur, breaking across the beach to spill tannic waters into the Gulf. At the same time, waves push salt water into the lake.
As trees sprout in the coastal strand and grow to provide a dense canopy, they change the habitat entirely. In the maritime hammock, or coastal hammock, wind-swept live oaks create a canopy above lush thickets of saw palmetto. Some of the most dramatic maritime hammocks are along the Atlantic Coast.
Brittle grasses and succulent plants such as glasswort and sea purslane grow along the edges of salt flats and salt marshes, where herons, egrets, and ibises stride through the shallows.
Estuaries and coastal savannas are extensive grassy salt marshes punctuated by islands of cabbage palms, typically found between barrier islands and the mainland. Along the Gulf Coast from Tampa Bay to Pensacola, they may be edged by seasonally wet pine flatwoods. Florida’s largest and most remote estuaries stretch along the shallows of the Gulf of Mexico where the Panhandle and peninsula meet at the Big Bend.
Mangroves grow particularly tall in South Florida, where in addition to mangrove swamps you’ll find dense mangrove forests along many coastlines.
In the Keys, a coastal berm develops between the mangroves and the shallow waters surrounding the islands, a sandy strand of low dunes and salt-tolerant vegetation.
Tidal Rock Barren
The unusual tidal rock barren of the Keys is a salt-tolerant plain, a flat landscape with white limestone slabs. It supports low scrubby shrubs like the bay cedar, and its character reminds us of the alvars of the Great Lakes.
The coastal prairie is shaped by the shallows of Florida Bay around the Everglades and Keys, creating stark salty wetlands supporting buttonwood on a base of sticky limestone marl.
Florida’s bedrock is primarily limestone. The Atlantic Coastal Ridge, which is made up of Anastasia limestone, outcrops along the Atlantic Coast to form dramatic rocky shorelines in several counties, including sea caves along Jupiter Island. On the Gulf Coast, occasional limestone outcrops occur along barrier islands. While tidal pools are rare in Florida, you will find them where these outcrops occur.
Coastal shell mounds, or middens, are not natural habitats, but were created by ancient peoples as waste heaps where they piled clam and oyster shells along Florida’s waterways. However, the limestone in the shells helped enrich these areas so maritime hammocks took root atop most of them. These are some of the more notable coastal shell mounds, which offer elevated views around the surrounding coastline.
While not habitats per se, there are unusual organic features to be found along some of Florida’s shorelines. Along the Atlantic Coast barrier islands are occasional outcrops of rocky reefs that aren’t actually rock: they are living worm reefs, created by reef-building tube worms (sabellariid) which can be found from Cape Canaveral south to Key Biscayne. Typically, beaches with these reefs will post warning signs for you to not climb on the “rocks,” since they are actually tubes that contain the worms and are fragile. They cement together grains of sand with their saliva. When you see odd-shaped rocks on an Atlantic beach that look like a splayed-out creature, that’s a live colony of reef worms. Don’t step on them.
Other organic features happen due to coastal erosion. When habitats are chewed into by wind and waves, unusual things can occur. For instance, Blackrock Beach at Big Talbot Island State Park. While the beach looks like it’s strewn with volcanic rocks – which are in turn covered in the sun-bleached trunks and limbs of fallen trees – the “rocks” are actually compressed plant matter much like peat.