North Atlantic Coastal Plain Brackish/Fresh & Oligohaline Tidal
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North Atlantic Coastal Plain Brackish/Fresh & Oligohaline Tidal Marsh Macrogroup: Tidal Marsh yourStateNatural Heritage Ecologist for more information about this habitat. This is modeledmap a distributiononbased current and is data nota substitute for field inventory. based Contact © Gary P. Fleming (Virginia Department of Conservation & Recreation Natural Heritage Program) Description: A graminoid-dominated wetland of fresh to slightly brackish zones along tidal rivers in very southeast Virginia and the southern shores of the James River. Water salinity varies from nearly fresh (oligohaline) in the drowned creeks and inland estuaries to saltier brackish water near the coast and on or near barrier island inlets. These marshes typically occur as complexes dominated by large graminoids such as salt hay, bulrushes, cattails, and rushes, sometimes with species-rich associations of shorter graminoids, forbs, and floating or submerged aquatics. Brackish marshes tend to be low diversity communities of intertidal flats cut off from direct oceanic influence by protective barrier islands. State Distribution: VA Total Habitat Acreage: 17,021 Ecological Setting and Natural Processes: Percent Conserved: 14.6% These marshes are associated with extensive brackish State State GAP 1&2 GAP 3 Unsecured water and both lunar and wind tidal flooding. The tidal State Habitat % Acreage (acres) (acres) (acres) freshwater marshes are driven by irregular wind tides, with VA 100% 17,021 240 2,252 14,529 minimal lunar tidal influence. Irregular flooding, fire, and sea- level rise are important drivers of ecological change. Similar Habitat Types: This system is mapped in extreme southeastern Virginia only, while the North Atlantic Coastal Plain Tidal Salt Marsh system is mapped from Chesapeake Bay north to southern Maine. In addition, it represents only brackish and fresh marshes; all salinity levels, salt, brackish, and oligohaline/fresh, are lumped together and mapped in the northern salt marsh system. Crosswalk to State Wildlife Action Plans: Crosswalk to State Name Examples: Places to Visit this Habitat: Habitat Patch Distribution Chippokes Plantation State Park | VA 7,000 First Landing State Park | VA 6,000 Nansemond National Wildlife Refuge | VA 5,000 4,000 Ragged Island Wildlife Management Area | VA 3,000 Acres 2,000 1,000 0 Associated Species: Appendix lists scientific names 0 to 1 1 to 5 5 to 10 1000+ BIRDS: american goldfinch, common yellowthroat, least bittern, 10 to 100 marsh wren, red-winged blackbird, song sparrow, swamp 100 to 1000 sparrow, virginia rail, willow flycatcher, yellow warbler Patch Size Classes The average patch size for this habitat is 5 acres and the largest single patch is MAMMALS: big brown bat, eastern pipistrelle, little brown 1,237 acres. This chart shows the proportion of the habitat that is in each patch-size myotis, northern long-eared bat, red bat, silver-haired bat class. PLANTS: Sandpaper Vervain (Verbena scabra) Age Class Distribution 100 80 60 40 20 0 Percent of Habitat 1 to 20 20 to 40 40 to 60 60 to 80 80 to 100100 to 140 Age (Years) This chart shows the average age of trees associated with this habitat based on forest Inventory data. For non-forested systems or small habitats the average age is Species of Concern (G1-G4): Appendix lists scientific names influenced by the surroundings. INSECTS: rare skipper Predicted Habitat Loss to Development 20,000 15,000 10,000 Acreage 5,000 0 2010 2020 2030 2040 2050 2060 Decade This chart shows the predicted loss of habitat over the next five decades (2,700 acres) if loss continues at the same rate as 1990-2000. The average rate of loss is 54 acres per year. Habitat Connectedness Index 60 40 20 0 Percent of Habitat 0 to 25 25 to 50 50 to 75 75 to 100 Degree of Fragmentation (0=Highly Fragmented & 100= Highly Connected) This metric measures how connected or fragmented the land directly surrounding (18 © Gary P. Fleming (Virginia Department of Conservation & Recreation Natural square miles) the habitat is, this the chart shows the proportion of the habitat in each Heritage Program) connectedness class. North Atlantic Coastal Plain Brackish/Fresh & Oligohaline Tidal Marsh http://nature.ly/HabitatGuide.