Chapter 4 Habitats
agriculture. Residential development can increase erosion during the construction process, but also as a secondary result of increased impervious surfaces in the watershed. Development pressure is likely to increase in the Coastal Plain, which will lead to a proliferation in impervious surfaces, increasing runoff, stream and bank erosion, and pollution inputs. Most watersheds in the Piedmont are already highly developed and have high percentages of impervious surfaces, leading to increased runoff, stream and bank erosion, pollution inputs, and increased flashiness of streams and rivers. Navigation Dredging . The US Army Corps of Engineers regularly maintains navigation channels by dredging waterways through coastal inlets, sounds, estuaries, and large rivers (Rosati and Kraus 2009) . Channelization can homogenize habitats as bed material and sediments are removed. Coastal dredging can also increase saltwater intrusion leading to changes in species composition and ghost forests on land. Impoundment. Dam construction has altered flows and river hydrology and morphology. Dams along the Yadkin, Pee Dee, and Catawba rivers are subject to coldwater releases and peaking flow regulation through licenses issued by the Federal Energy Regulatory Commission. Many rivers in the Piedmont that were once free flowing are now flooded by reservoirs, severely fragmenting habitat and often isolating populations of species upstream and downstream of the impoundment. Indirect effects to the unimpounded portions of the system include disruption of natural thermal and hydrologic regimes and a reduction in downstream flows. These impacts will have a negative influence on aquatic habitat as well as reduce the base flow available for drinking water for downstream municipalities. Water Quality. Increased stormwater runoff will amplify the loading of nutrients, sediment, and contaminants into streams, rivers, and reservoirs. The increased loads could affect water quality and habitat for aquatic species, as well as drinking water for municipalities. Stormwater controls and retrofits will become increasingly important (Band and Salvesen 2010). Storms. Because of potential changes in storm frequency and intensity, it is likely that channel hydrodynamics will be altered. Changes in flow regime, sediment transport, and overall channel design are associated with channel hydrodynamics. The current pattern of riffles, runs, and pools may be altered, creating changes in aquatic species’ habitats. In these large rivers, gravel and sand bars may be displaced and formed in other locations, and reservoirs may experience increased sediment deposits. How or if species adapt to changing habitats will require close monitoring to observe trends and help inform future management decisions (Bakke 2008) . Invasive Species . The introduction of any invasive species is cause for concern and the prevalence of warmer water temperatures may increase the likelihood of exotic species becoming established that were previously thought to be non-threatening because the winters were too cold for survival.
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2025 NC Wildlife Action Plan
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