Pea Island National Wildlife Refuge is
situated on a typical southeastern United States barrier island system with
ocean beach, dune, brackish ponds, and marsh communities dissected by tidal
creeks containing submerged aquatic vegetation. The refuge’s plant communities
have been affected by human development activities over time. Some of these
activities occurred before the Service established the refuge and some have
occurred since. The most notable products of those activities today are
artificial dunes, North Carolina Highway 12, the Herbert C. Bonner Bridge, and
three impoundments. Although natural dunes occur, the Civilian Conservation
Corps first constructed some oceanfront dunes in the 1930s and, since then,
agencies have vegetated and maintained them for various reasons. The primary
reason for dune maintenance on the refuge today is protection of North Carolina
Although a sand trail pre-dated the
refuge, the state did not pave what is now North Carolina Highway 12 until the
1950s, and the state has relocated much of it westward since its initial
construction. The Service constructed three man-made impoundments in the late
1950s and 1960s to enhance habitat quality for migratory waterfowl. The plant
communities today reflect succession since the late 1930s, with some areas
being subjected to ocean overwash, agricultural practices in the refuge’s early
years, and prescribed fire. More recently, prescribed fire has substantially
altered plant communities and successional stages on most of the refuge.
The brackish marsh community occurs along the margins of sounds and
estuaries in areas not subjected to regular flooding by salt water. Often
referred to as “high marsh,” this community is subjected to irregular flooding
mostly from wind tides along the Outer Banks.
Dune Grass Community
The Dune Grass Community occurs immediately landward of the Upper Beach community
and is subject to exposure to salt spray and abrasive, wind-blown sand. These communities
are excessively drained due to the nature of the substrate and are subject to
frequent shifting unless stabilized through artificial means. Learn More
Exposed Overwash Flats Community
The exposed overwash flat community is located on marine flats, not
otherwise considered part of the current beach. These flats are direct results
of overwash during storm events. These flats are the unvegetated, sandy areas
adjacent to beaches and inlets that can have high shell content.
The managed wetlands are manmade impoundments with borrow canals around
the perimeter that may include open water, moist soil, exposed sand/mud flats,
and emergent vegetation with varying amounts and management regimes. Pea Island
National Wildlife Refuge has three impoundments: 390-acre North Pond, 192-acre
New Field Pond, and 208-acre South Pond.
Maritime Dry Grassland
The Maritime Dry Grassland Community occurs on low,
stable dunes and sand ridges. It also occurs in overwash terraces behind or
between dunes in areas subject to inundation by the ocean or partial burial due
to wind-blown sand.
Maritime Shrub Community
The Maritime Shrub community occurs in a wide range of conditions from excessively
to poorly drained soils in areas protected from salt spray and flooding by salt
water. These conditions may occur on stabilized sand ridges, in dune swales,
and on sand flats.
Ocean Beach Community
The Ocean Beach Community is the unvgetated beach and can be divided
into the lower beach below the mean high water level and the upper beach above
mean high water level. The lower beach is the exposed portion of the beach
between the mean high tide and mean low tide lines.
Salt Flat Community
The salt flat community occurs in estuarine areas subjected to irregular
flooding by salt water. It occurs in shallow depressions wherein evaporation of
the high salinity ocean water concentrates salt. Sparse cover and low diversity
characterize its plant density and species composition.
The Salt Marsh community occurs on the margins of sounds, estuaries, and
other coastal waters. Salt marsh occurs on the landward side of barrier island
systems in areas under tidal influence.