Chapter 4 Habitats
4.2.7 Headwater Streams/Small Creeks 4.2.7.1 Ecosystem Description
The headwater stream and small creek community includes intermittent and first- and second- order streams and make up the largest proportion of drainage reaches in the landscape (Leopold et al. 1964; Meyer et al. 2007; Gothe et al. 2014) . The majority of land area in North Carolina (approximately 80%– 85%), drains to headwater streams ( Gregory 2009 ) and constitutes at least 80% of the nation's stream network ( Meyer et al. 2003 ). Headwater streams are very important elements in the stream and river networks in terms of influencing water quality and quantity. A stream classification system using drainage area (DA) as a break for size classes, similar to those described in the Northeast Aquatic Habitat Classification System and the National Fish Habitat Framework, has been applied to this aquatic community description. The hierarchical classification system shown in Table 4.1-1 ( Appendix 4 ) defines headwater streams as having a drainage area of 40 square miles or less (Olivero and Anderson 2008; Olivero-Sheldon and Anderson 2013 ). Stream size affects the aquatic biological assemblages within a stream reach (Vannote et al. 1980; Higgins et al. 2005; Olivero-Sheldon and Anderson 2013) . Species diversity tends to be lower in headwater systems when base flow conditions are highly variable. Overall, species richness is typically lower than in small river systems and is often composed of the most common generalist species; mussels are often absent from headwater streams. In these aquatic communities, the coarse organic matter from riparian vegetation provides energy resources for what is often a consumer community dominated by shredding insects (Olivero-Sheldon and Anderson 2013) . Benthic macroinvertebrates are a very important component of the community, and aquatic insect species richness can be very high even in headwaters in agricultural and urban landscapes (Moore and Palmer 2005; Meyer et al. 2007) . Headwater streams in the Mountain ecoregion are influenced by location on the landscape. Persistent water temperatures will determine whether they are considered coolwater systems or coldwater systems. Headwater streams found in other areas of the state are more likely to be considered warmwater systems. Warmwater systems are those that have water temperatures that are persistently greater than 25°C (77°F). Water temperature contributes significantly to the species assemblages that occur in aquatic environments. 4.2.7.2 Location of Habitat These systems can be found statewide but are more prevalent in the Mountain and Piedmont ecoregions. Headwater systems may be associated with small wetland systems, and some originate at natural spring heads. Many streams in this community type are unnamed tributaries; however, examples include Morgan Creek, Parkers Creek, Little Creek, and White Oak Creek.
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2025 NC Wildlife Action Plan
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