Chapter 4 Habitats
Table 4.2.12-1. Climate change compared to other threats to natural lakes Threat Rank Order Comments
Climate change will potentially have a direct influence on availability of thermal habitats in aquatic environments, which in turn can become a constraint to feeding habitat access and subsequent consequences on species growth (DeWan et al. 2010) .
Climate Change
4
4.2.12.5 Impacts to Wildlife Appendix 3 includes a list of SGCN and other priority species for which there are knowledge gap and management concern priorities. Appendix 3-18 identifies SGCN that use natural lake systems. In particular, natural lakes and immediately adjacent cover (especially the smaller ponds) provide habitat for wading birds and shorebirds for foraging and important breeding 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 becoming 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, fishing, crabbing, 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 fluctuations are expected to affect the shoreline but not have major effects 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 affected. Low water may combine with the effect of warmer water to produce low oxygen levels that will stress the aquatic community. Temperature and DO concentrations control the distribution of fish species in lakes (Stefan et al. 2001 in DeWan et al. 2010), which will have significant impacts on shallow waters as ambient temperatures increase. In ponds and lakes deep enough to exhibit summer thermal stratification, warmwater habitat will increase in depth, potentially forcing cool water organisms 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 fishes were 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 fishes and a 0% to a 31% increase in habitat for warmwater fishes (DeWan et al. 2010) .
4 - 97
2025 NC Wildlife Action Plan
Made with FlippingBook Ebook Creator