4.2 Aquatic Communities
dispersing species have invaded reservoirs, spread through interconnected waterways and been unwittingly transported on boating equipment and in bait buckets. Exotic plant spe- cies such as Hydrilla, Giant Salvinia, and Purple Loosestrife can form large mats that dis- place native vegetation and entangle boat motors. Exotic aquatic animals such as the Asian Clam, carp (e.g., Common, Grass, Bighead) and snails (e.g., Chinese and Japanese Mystery Snails, Red-Rim Melania) are often vectors for parasites and diseases that can afect 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 fow 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 is 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 fows are reduced in the study streams, fsh in reaches above impoundments are apparently forced downstream to seek shelter in the impoundment, or survive in wet- land areas that provide temporary refuge (Kashiwagi and Miranda 2009) . Despite annual fuctua- tions, fsh 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) . 4.2.13.4 Climate Change Compared to Other Threats Comparing climate change to other ecosystem threats can help defne short- and long-term conservation actions and recommendations. While climate change in many cases is not the most severe threat, a combination of synergistic efects with other existing conditions could stress aquatic systems to the point where native species are unable to persist. A comparison of climate-related impacts to other threats is not included in this description because the NCNHP vulnerability assessments completed in 2010 did not include reser- voirs and impoundments as a community type. Concerns are expected to be similar to the comparison results for other aquatic systems; however, sedimentation and erosion, inva- sive species, and pollution are primary concerns for this community type.
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2015 NC Wildlife Action Plan
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