4.2 Aquatic Communities
Because of potential changes in storm frequency and intensity, it is likely that channel hydrodynamics will be altered. Associated with channel hydrodynamics are changes in fow regime, sediment transport, and overall channel design. Changes may occur in aquatic species’ habitats, and how or if these species adapt to changing habitats will require close monitoring to observe trends and help inform future management decisions (Bakke 2008) . 4.2.7.4 Climate Change Compared to Other Threats Tese stream systems are vitally important to the overall health of the downstream water- shed, yet are likely to experience potentially severe physical, chemical, and biological changes with temperature and DO alteration ( DeWan et al. 2010; Karl et al. 2009; Band and Salvesen 2009 ). Table 4.8 provides a review of expected climate change impacts in order of impor- tance in comparison with other types of threats. 4.2.7.5 Impacts to Wildlife Appendix G includes a list of SGCN and priority species for which there are knowledge gap and management concern priorities. Appendix H identifes SGCN that use Headwater Streams. Headwater systems ofer a range of habitats that can support an abundance and diversity of species, depending on water depth and seasonality of fows, hydrologic regime, tempera- ture, water chemistry, substrate types, and connectivity to downstream systems (Meyer et al . 2007). Biodiversity will be infuenced by the presence of species unique to headwater sys- tems and whether connectivity within the DA allows species that seasonally use headwa- ters for particular life history stages (e.g., spawning, nursery areas) to move upstream from larger streams (Meyer et al . 2007). Headwater systems, especially those associated with springs and seeps, are likely to have a high diversity of insects, especially those genera with an aquatic life history cycle. Research conducted at Coweeta Hydrologic Laboratory in west- ern North Carolina collected at least 51 families and 145 genera of aquatic insects in eight headwater streams during three decades of sampling (Meyer et al . 2007) . Climate change efects, especially drought and higher temperatures, will likely have a sig- nifcant impact on headwater stream communities, possibly creating a shift where several perennial streams will become intermittent or ephemeral systems. Tis potential shift will result in the loss of aquatic species diversity. Aquatic species could experience shifts in their range or distribution and sensitive species may experience decline or extirpation due to changes in water quality and habitat. Headwater streams could dry up, potentially leading to aquatic species extirpation (DeWan et al. 2010; Karl et al. 2009; Band and Salvesen 2009; Holman et al. 2010) .
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2015 NC Wildlife Action Plan
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