marsh: meaning wetland that is dominated by herbaceous rather than woody vegetation saltmarsh...

Salt Marsh

Chris Jones

Charateristics

Marsh: meaning wetland that is dominated by herbaceous rather than woody vegetation Saltmarsh cordgrass (Spartina alterniflora) dominates the

seaward edge and borders of tidal creeks, areas most frequently inundated by the tides. Needle rush (Juncus roemerianus) dominates higher, less frequently flooded areas

Carolina sea lavender (Limonium carolinianum) Perennial saltmarsh aster (Symphyotrichum tenuifolium) Wand loosestrife (Lythrum lineare) Marsh fimbry (Fimbristylis spadicea), Shoreline seapurslane (Sesuvium portulacastrum).

Dominant vegetation

Saltmarsh cordgrass (Spartina alterniflora) dominates the seaward edge and borders of tidal creeks, areas most frequently inundated by the tides.

Natural processes

Flooding frequency and soil salinity are the two major environmental factors that influence salt marsh vegetation (Montague and Wiegert 1990).

Saltmarsh Cordgrass: found where marsh is flooded almost daily. It dominates low marsh (portion below mean high water level)

Needlerush: found where marsh is flooded less frequently and in theportion above mean high water level.

Fire

Lightining Spread from nearby uplands; natural

bariers(tidal creeks and salt barrens) Needle rush Replaced by upland species Seaside sparrows

Values

Mullet (Mugil spp.) Spot (Leiostomus xanthurus) Blue crabs (Callinectes sapindus) Oysters (Crassostrea virginica) Shrimp (Penaeus spp). Red drum (Sciaenops ocellatus), Spotted seatrout (Cynoscion nebulosus)

Salt marsh soils

Salt marsh soils range from deep mucks with high clay and organic content in the deeper portions to silts and fine sands in higher areas.

The organic soils have a high salinity, neutral reaction, and high sulfur content.

Range

Salt marshes cover roughly 170,000 hectares in Florida (Montague and Wiegert 1990)

Rare plants

Godfrey’s spiderlily (Hymenocallis godfreyi)endemic to Wakulla County

Golden leather fern (Acrostichum aureum) in South Florida.

Beaked spikerush (Eleocharis rostellata) along brackish shores in the Florida Panhandle.

Rare species

The saltmarsh topminnow (Fundulus jenkinsi) is found in tidal channels in western Panhandle and ranges west to Texas.

Atlantic salt marsh snake (Nerodia clarkii taeniata)

Gulf coast salt marsh snake (N. c. clarkii)

The American crocodile (Crocodylus acutus) utilizes salt marsh as well as mangrove swamp at the south end of the Florida peninsula, in the Florida Keys, and on islands in Florida Bay.

Nesting birds MacGillivray’s (Ammodramus maritimus macgillivraii) Scott’s (A. m. peninsulae) Louisiana (A. m. fisheri)

Worthington’s marsh wren (Cistothorus palustris griseus) Marian’s marsh wren (C. p. marianae)

Birds

Florida clapper rail (Rallus longirostris scottii The black rail (Laterallus jamaicensis) Wading birds Reddish egret (Egretta rufescens) Tricolored heron (Egretta tricolor) Roseate spoonbill (Platalea ajaia). White ibis (Eudocimus albus) Little blue heron (Egretta caerulea) In South Florida, Great white heron (Ardea herodias

occidentalis).

Rare mammals

Common rice rat (Oryzomys palustris) has two rare varieties in Florida: the Sanibel Island rice

rat (O. p. pop. 2) and the key rice rat (O. p. pop. 3).

The Salt marsh vole (Microtus pennsylvanicus dukecampbelli).

Southern mink (Neovison vison pop.1),

Gulf salt marsh mink (N. v. halilimnetes (N. v. lutensis)

The Lower Keys rabbit (Sylvilagus palustris hefneri)

Variant

Salt flat: Slightly higher areas within the marsh, flooded only by storm tides or extreme high tides and isolated from freshwater influx from the surrounding uplands, become very saline and desiccated due to evaporation.

These areas are dominated by species that can tolerate high salinities, consisting of either succulents, such as

saltwort (Batis maritima), perennial glasswort (Sarcocornia ambigua), annual glasswort (Salicornia bigelovii), bushy seaside oxeye (Borrichia frutescens), or short grasses, saltgrass (Distichlis spicata), seashore paspalum (Paspalum vaginatum), and shoregrass (Monanthochloe littoralis).

Community variations

On the Gulf coast, with a low tidal range of 0.6 to 0.9 meters (2 to 3 feet) and gentle seaward slope, most of the marsh is above mean high water level and is dominated by needle rush, with saltmarsh cordgrass often forming only a fringe along the seaward edge of the marsh and along tidal creeks

On the northeast coast with a tidal range of 1.4 to 1.8 meters (5 to 6 feet), most of the marsh at the river mouths is below mean high water and is dominated by saltmarsh cordgrass, with needle rush confined to a fringe on the landward margin

Management

Management considerations

Currently about 65 percent of the total area of salt marsh in the state is protected on conservation lands and aquatic preserves

Global Rank : G5 State Rank: S4

Questions?