4.3 Wetland Natural Communities
occasionally on high ridgetops. Tey have a closed canopy of wetland trees. Understory, shrubs, and ground cover are usually sparse.
• Ephemeral (temporary) pools that are small, seasonally fooded depressions with gently sloping sides and are usually found in sandy uplands. • Seeps that occur along slopes where groundwater trickles out of the surface and collects in small pools and will often trickle into streams. • Clay-based upland depressions that typically occur as oval or round depressions with a clay base that allows them to hold water for at least a portion of the year. In the Sandhills and Coastal Plain, these depressions historically have had a Longleaf Pine upland where hot season fres burned regularly, creating an open-canopy, grassy wet- land system with long hydroperiods. In the Coastal Plain and Sandhills ecoregions, pond basins may also be limesink depres- sions, Carolina bays, or swales between recent or older sand dunes. • Limestone sinks occur over limestone formations. Scattered trees (Pond Cypress and Swamp Blackgum) may be present in both deep and shallow water zones and most ponds are surrounded by a dense shrub layer. Tese shrubby zones provide breeding habitat for shrub-scrub-nesting birds (Hunter et al. 2001a; Johns 2004) and these sites are used by wading birds for foraging/nesting and amphibians for breeding. • Swale wetlands occur on barrier islands, such as in the Outer Banks, in areas where the freshwater aquifer saturates the soil and collects on the surface between sand dunes. Tese ponds will also have dense maritime shrublands in areas where water is shallow; in deeper water, they are characterized by emergent and submerged aquatic vegetation. • Carolina bays with organic/peat substrates are relatively deep closed basins associated with pocosins, depression swamps, Pond Pine woodlands, bay forests, or Atlantic White Cedar forests. Occasionally they occur in shallow depressions associated with nonriv- erine communities such as swamp forests, wet hardwood forests, and wet marl forests with nonalluvial mineral soils (NCNHP 2010) . All of these natural community types often have abundant amphibian species. Tose that dry annually or semi-annually beneft amphibians the most, due to the absence of fsh, which would typically eat amphibian eggs and larvae. During heavy storm events, how- ever, fsh can be swept in by overbank fooding, reducing the suitability of these pools for amphibian breeding until they dry out again.
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2015 NC Wildlife Action Plan
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