Chapter 4 Habitats
Table 4.2.3-2. Climate change compared to other threats to coldwater systems.
Rank Order
Threat
Comments
4 Conversion of land, both from forest to agriculture or silviculture, as well as from development projects, continues to threaten stream integrity, resulting in increased sediment, bank erosion, and stormwater runoff containing sediment and other potentially toxic materials. Timber harvests with improper erosion controls and poorly constructed and maintained timber roads can cause erosion. 4 Effects are both direct and indirect, including loss of habitat, shifts in food web, and change in species composition. Numerous watersheds in the Mountains no longer contain trout assemblages likely due to a proliferation of ponds that not only block fish movements but also cause decreased stream flows and increased water temperatures. 5 Invasive plants in the riparian area can have negative impacts on stream systems by creating a monoculture (e.g., Japanese Knotweed) with poor nutrient inputs, reducing bank stability, and allowing too much sunlight to infiltrate, resulting in warmer stream temperatures. The Asian Clam or Rusty Crayfish may compete for space and resources, although specific interactions are largely unknown.
Conversion to agriculture/ silviculture
Impoundment/ Dams
Invasive Species
4.2.3.5 Impacts to Wildlife Appendix 3 contains lists of SGCN and knowledge gap, management concern, or management need priority species. Appendix 3-18 provides a list of SGCN associated with coldwater habitats. Coldwater stream communities contain several rare species that are at risk of extirpation or extinction because they are vulnerable to warming water temperatures and other water quality changes. Several SGCN and priority species have very limited distributions or, if widely dispersed, have small populations (e.g., Eastern Spiny Softshell Turtle, Loggerhead Musk Turtle, Junaluska and Longtail Salamanders). Isolation or habitat fragmentation could affect life cycle or prey components for a variety of species. Trout populations in our state are already at the southern end of their range, and the native Brook Trout should be a species considered vulnerable to extinction in this ecosystem group. They typically occupy the upper reaches of mountain headwater streams, and few populations have the ability to migrate to colder waters. Typically, trout are unable to survive in waters where temperatures rise above 20°C–24°C during summer. Because of the already limited range of trout in North Carolina, it is unlikely these fish will be able to seek refuge from warming water temperatures. It should be noted that Weaver (2010) examined the effects of trout stocking on native nongame fishes and found no significant differences in fish density, species richness, species diversity, or fish microhabitat use associated with short-term effects of trout stocking.
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2025 NC Wildlife Action Plan
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