Chapter 4 Habitats
4.2.14 Estuarine Aquatic Communities 4.2.14.1 Ecosystem Description
Estuarine aquatic communities are represented by the sounds and near-shore waters along North Carolina’s coast. North Carolina’s estuarine aquatic communities represent the largest estuarine systems along the United States Atlantic coast and include the Albemarle, Pamlico, Core, Back, Croatan, Currituck, Roanoke, and Bogue sounds. These sounds are collectively a part of the Albemarle-Pamlico National Estuary Partnership (APNEP), a cooperative effort jointly sponsored by North Carolina and Virginia state resource agencies. They receive freshwater drainage from rivers and tributaries of the White Oak, Neuse, Tar-Pamlico, Roanoke, Pasquotank, and Chowan River basins. Estuaries in the southern portion of the state flow more directly into the ocean, creating small but important areas of estuarine aquatic habitats within the lower reaches of the Cape Fear and within the Lumber River basin. Near-shore waters are located within three nautical miles of North Carolina’s coastal land area and are marine waters. Through tidal influences and storm surge events, near-shore waters contribute saline water to the estuaries. This mixing of freshwater from rivers and tributaries with saline waters from near-shore and ocean marine waters contributes to seasonal and temporal variability of salinity in the brackish waters within the estuaries. This habitat is closely associated with the estuarine and freshwater marsh wetland communities described in Section 4.3. Coastal waters represent a range of water salinities that depend on freshwater inputs from rivers and streams and mixing from wave-driven motions and subsurface flow. Coastal freshwaters generally have salinity levels between 0 and 0.5 ppt as defined by the Venice System (Cowardin et al. 1979) . Average ocean water salinity levels are between 25 and 35 ppt (Reshetiloff 2004) . Salinity is typically less than 5 ppt in the sounds and can be vertically homogeneous in the water column according to the South Atlantic Fishery Management Plan (SAFMC 1998) . Coastal shallow water temperatures along the North Carolina coast typically reach 31°C–33°C (Burkholder et al. 1992, 1994; Mallin et al. 2000a). The NC Coastal Habitat Protection Plan (CHPP) refers to estuarine waters as essential fish habitat (EFH) (NCDEQ 2021) . EFH supports the different life cycles of approximately 1,000 aquatic species managed under the South Atlantic Fisheries Management Plan (SAFMP), including anadromous species such as Striped Bass, herring species, and sturgeon species that migrate to freshwaters to reproduce (SAFMP 1998) . The CHPP and SAFMPs describe five EFH components of the estuarine aquatic communities in North Carolina and are described below: • Soft Bottom is the unconsolidated, unvegetated sediment that occurs in freshwater, estuarine, and marine systems. It is an important component of designated Primary Nursery Areas (PNAs), Anadromous Fish Spawning Areas (AFSA), and Anadromous Nursery Areas (ANA) (Street et al. 2005) .
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2025 NC Wildlife Action Plan
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