Chapter 4 Habitats
Because of the link between freshwater mussels and fish, phenological disruptions are a possibility, but exact mechanisms or effects are not understood. Freshwater mussel larvae (glochidia) are dependent on a host fish for transformation into juveniles. Host fish species are known for some mussel species but not well understood. Temperature cues play a large role in the release of glochidia from female mussels and in the movement and migrations of fish. With changing temperatures predicted with climate change there could be phenological disruptions affecting the reproductive capacity of freshwater mussels. Recent studies have shown that EDCs in treated wastewater can inhibit reproduction and cause feminization of mussels and fish. Although little is known about the effects of EDCs, additional studies are being conducted to document the levels of EDCs in discharges. Wastewater treatment facilities need to incorporate appropriate measures 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) . While this community represents riverine aquatic habitats, there are terrestrial species that use this resource. Several priority bird species are threatened by rising sea levels through habitat conversion from saltwater intrusion; loss of nesting, foraging, or cover habitats from inundation; and impacts that reduce prey species found in this habitat. For example, the Little Blue Heron and Wood Stork prefer freshwater pools, inland swamp, or mudflats and usually nest farther inland (LeGrand et al. 2012) . Inundation and saltwater intrusion will reduce habitat quality and availability and potentially displace birds when currently occupied habitats are converted to brackish systems. Most of the listed priority amphibian and reptile species associated with riverine aquatic habitats have limited distributions, or little is known about their distribution, or they are widely dispersed but have small populations. Isolation or fragmentation of particular habitat stretches occupied by those species could have significant long-term effects upon the sustainability of those populations in North Carolina. Temperature may have significant effects on developmental pathways or behaviors influencing reproduction and survival. For example, sex determination in hard-shell turtles is largely temperature dependent (Bull 1980, Bull et al. 1982) . Rising temperatures can also affect metabolic and growth rates in insects and other ectotherms (Dukes et al. 2009; Sheridan and Bickford 2011) , resulting in faster development and shorter lifecycles in some cases. Increased winter temperatures and frost-free days may also affect overwinter survival of some insects and pathogens (Dukes et al. 2009) , resulting in increased population sizes that contribute to outbreaks. 4.2.11.6 Recommendations Section 4.2.2 provides recommendations appropriate for all aquatic communities, statewide. Actions specific to the river basins that contain stream swamp communities are provided in Section 4.5.
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2025 NC Wildlife Action Plan
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