4.2 Aquatic Communities
Pollution. Decreased stream fows can allow an accumulation of sediment and chemical inputs from stormwater runof and efuent discharge because there is less frequent fush- ing in the system. Recent studies have shown that endocrine-disrupting chemicals (EDCs) in treated wastewater can inhibit reproduction and cause feminization of mussels, fsh, and some amphibians (Hayes et al. 2006; Elrod et al. 2003a, 2003b; Huang et al. 2003a, 2003b) . Although little is known about the efects of EDCs, additional studies are being conducted to document the levels of EDCs in discharges, and measures are being identifed to reduce or eliminate EDCs from wastewater prior to discharge, should those discharge studies show increases in EDC levels (Conn et al. 2006; Kim et al. 2007; Kasprzyk-Hordern et al. 2008; Joss et al. 2006; Kolpin et al. 2002; Nowotny et al. 2007) . Phenology Changes. Tere is a life history link between freshwater mussels and fsh, and the mechanisms or efects of phenological disruptions are unknown at this time. Freshwater mussel larvae (glochidia) are dependent on a host fsh for transformation into juveniles. Temperature cues play a large role in the release of glochidia from female mussels and also in the movement and migrations of fsh. Terefore, predicted changing temperatures could cause phenological disruptions afecting the reproductive capacity of freshwater mussels. As water temperatures increase, freshwater mussels inhabiting cool water systems could experience a shift in their range, moving into previously coldwater systems as their host fsh move upstream. Storms. Increased storm intensity can lead to fooding and therefore increased stormwa- ter runof and erosion. With increased stormwater runof, there is an increase in loading of sediments, nutrients, and contaminants into streams and potential negative efects on biota, such as fsh kills. With a change in the intensity and variability of rainfall, there are potential changes to stream fow patterns, channel hydrodynamics, and the volume of groundwater (Band and Salvesen 2009; Holman et al. 2010; Bakke 2008) . An increase in the number of tropical events can lead to fash fooding, which causes many of the abovementioned responses. Efects such as increased sediments and contaminants into aquatic systems, in addition to major disruption to channel design and hydrodynamics, potentially upset the physical, chemical, and biological structure of streams (Band and Salvesen 2009) . Heavy rainfall events have been documented in the western mountains of the state (Keim 1997) and have contributed to soil erosion, sedimentation, and stream dynamics (DeWan et al. 2010) . An increase in the number of tropical events can lead to fash fooding, which causes many of the abovementioned responses and landslides, which are of particular concern in mountainous, high-elevation areas. Landslides lead to increased sediments and contami- nants in aquatic systems, in addition to major disruption to channel design and hydrody- namics, potentially upsetting the physical, chemical, and biological structure of streams (Band and Salvesen 2009) .
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2015 NC Wildlife Action Plan
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