Chapter 4 Habitats
periodic low levels of DO due to hypolimnetic discharges and peaking power production releases from Chatuge and Nottely dams. Impoundment and thermal alteration may further affect native species by fragmenting suitable habitat and isolating historically contiguous populations in tributaries. Invasive Species . Reservoirs can be a barrier to upstream movement of invasive aquatic species, but more often they act as stepping-stones for the dispersal of exotic and nonnative species across landscapes. Exotics are species that are not native to the United States, and species that are not native to North Carolina, but that may be native to other areas of the United States, are considered nonnatives. Havel and colleagues (2005) conducted a study called “Do Reservoirs Facilitate Invasions into Landscapes?” that examines how reservoirs might facilitate the spread of invasives across landscapes. Populations often become invasive because there are no natural predators or conditions to control growth (NCDEQ 2025c) . A variety of passively dispersing species have invaded reservoirs, spread through interconnected waterways and been unwittingly transported on boating equipment and in bait buckets. Exotic plant species such as Hydrilla, Giant Salvinia, Lyngbya, and Purple Loosestrife can form large mats that displace native vegetation and entangle boat motors. Exotic aquatic animals such as the Basket Clam, carp (e.g., Common, Grass, Bighead) and snails (e.g., Chinese and Japanese Mysterysnails, Red-Rim Melania) are often vectors for parasites and diseases that can affect native species. Climate Impacts. Many of the water quality and water quantity impacts resulting from climate change are analogous to impacts from economic development and population growth in North Carolina. Climate change is predicted to decrease rainfall and therefore limit water supply, while growth and development have been increasing and continue to raise demands for water supply. Historical stream flow patterns are projected to be altered due to climate change impacts; however, these are already being altered due to rapid urbanization. Global warming scenarios predict a possible decrease in precipitation and increase in evaporation (Jacobs et al. 2000), which together with sediment accumulations in our aging reservoirs, are likely to propel new constructions such as those being considered and pursued in the southeastern region of the country (Kashiwagi and Miranda 2009) . During drought periods when stream flows are reduced in the study streams, fish in reaches above impoundments are apparently forced downstream to seek shelter in the impoundment or survive in wetland areas that provide temporary refuge (Kashiwagi and Miranda 2009) . Despite annual fluctuations, fish communities of unimpounded headwater streams can remain fairly stable over time but require connectivity with the downstream community to preserve their integrity (Moyle and Vondracek 1985; Ross et al. 1985) .
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2025 NC Wildlife Action Plan
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