4.2 Aquatic Communities
sites for species such as Green Herons. Common Yellowthroats and Red-winged Blackbirds are typical nesters in vegetation along shorelines, and swallows and swifts often forage over lakes and ponds. Bald Eagles and Ospreys nest and/or forage at these sites, and waterfowl roost, loaf, and feed during migration and winter. Double-crested Cormorants are becom- ing common year-round residents at most coastal lakes. Anhingas are sometimes seen during summer, nesting at millponds and/or natural lakes. In addition, these water bodies are popular destinations for human recreational activities such as canoeing, fshing, crab- bing, and swimming. Multi-year droughts in the last several decades have produced long periods of low water. Most lakes are large enough that water level fuctuations are expected to afect the shore- line but not have major efects on the majority of the aquatic community. However, because the slope of most lake beds is very shallow, a large band of lake bed can become exposed during a multi-year drought. Mussels and any other sessile animals near the shore may be afected. Low water may combine with the efect of warmer water to produce low oxygen levels that will stress the aquatic community. Temperature and DO concentrations control the distribution of fsh species in lakes (Stefan et al. 2001 in DeWan et al. 2010), which will have signifcant impacts on shallow waters as ambient temperatures increase. In ponds and lakes deep enough to exhibit summer thermal strat- ifcation, warmwater habitat will increase in depth, potentially forcing cool water organ- isms into deeper waters (Allan et al. 2005 in DeWan et al. 2010; Ficke et al. 2007) . In Mohseni et al. (2003) , changes in habitat for cool and warmwater fshes was dependent on the assumptions for minimum temperature tolerance (32°F vs. 35.6°F) and ranged from a 12% to a 15% decrease in habitat for coolwater fshes and a 0% to a 31% increase in habitat for warmwater fshes (DeWan et al. 2010) . Development and loss of associated riparian habitats are concerns where Bald Eagles have found shorelines to use as perch/foraging sites. Lake Ellis Simon in Craven County is productive and holds a sizable Anhinga colony. Tese sites and immediately adjacent cover provideforaging and breeding habitats for species such as Green Herons. Terrestrial ani- mals that use lake communities for forage, refugia, or during parts of the reproductive cycle will also be afected by any changes in aquatic habitat or species community structure. Exotic species (e.g., Hydrilla , Asian Clam, carp) negatively afect native frogs and turtles due to decreased native plant and animal diversity. Avian Vacuolar Myelinopathy (AVM) is a disease that afects birds that use these habitats. It has killed nearly 100 Bald Eagles in the Southeast and is associated with a novel Cyanobacterial species found in aquatic plants such as Hydrilla.
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2015 NC Wildlife Action Plan
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