Chapter 4 Habitats
4.4.18 Sand, Shell, and Wrack Active Shoreline 4.4.18.1 Ecosystem Description
North Carolina's coastline features a string of barrier islands, long and mostly narrow islands that lie parallel to the mainland and were formed by naturally occurring offshore sand or sediment deposited over geological time. They are separated from the mainland by relatively shallow sounds, bays, tidal inlets, or the mouth of large river systems that drain to the Atlantic coast (NOAA 2014) . Natural forces such as wind, waves, and storms act on these islands, causing constant change, movement, erosion, and growth. Interior to the natural barrier islands, maintenance dredging of the Atlantic Intercoastal Waterway and various tidal inlets along North Carolina's coast produces sand that has been used to create artificial spoil islands located near the barrier islands. Both island types provide shoreline habitats that are important to wildlife. The active sand, shell, and wrack shoreline is composed of sand, small shells, shell debris, seaweed, and other marine detritus deposited between the low and high tide line. Water movement within the swash zone (Kelly and Dodd 2010) and saltwater inundation from tidal flooding along the beach prohibit plant growth, so vegetation communities are not included in this community type. The structure and availability of beach landscapes are subject to naturally occurring changes caused by wave action (swash), high tides, and storm surge and can vary daily (FitzGerald et al. 2007) . This habitat is often referred to as ‘beach’ but represents a different community than described in Maritime Grasslands, Dunes and Beach (Section 4.4.16). However, maritime grassland, maritime forest, tidal wetlands, and estuarine wetlands are the vegetated communities most likely to be located adjacent to this community. This habitat provides important forage sites for several species of resident and migrating shorebirds as well as decapod crustaceans (e.g., Ghost Crabs) (Schlacher and Lucrezi 2010) . Most shorebirds feed above the swash limit to a few meters into the water, while others feed on the beach above the active swash limit such as Ruddy Turnstones and Sanderlings (Burger et al. 1977; Nordstrom et al. 2006) . Where the active shoreline transitions to other community types it may provide nesting sites. They are also vital nesting sites for sea turtles and Diamondback Terrapins, and they support numerous other small mammals and invertebrates. Beach communities that are subject to low-energy wave action provide important spawning habitat for marine animals such as Horseshoe Crabs (family Limulidae ) (Nordstrom et al. 2006; NOAA 2014) .Sandy beaches also have a rich interstitial community comprising both micro- and macrofaunal species (e.g., Hydrozoa, Turbellaria, Trematoda, Nematoda, Gastropoda, Arthropoda) (McLachlan and Brown 2010) . 4.4.18.2 Location of Habitat Sand, shell, and wrack shoreline is coastal zone habitat found on barrier islands and other Atlantic Ocean shore and estuarine areas between the low tide line and the vegetated lower sand dune (fore dune) communities.
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2025 NC Wildlife Action Plan
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