Chapter 4 Habitats
4.4.9.3 Problems Affecting Habitats Conditions vary considerably within this habitat type, with a significant number having been impacted and/or lost due to numerous factors, while others remain functional “natural sites” and still others are specifically managed to minimize human impacts. Climate Change. Low-elevation cliffs and rock outcrops are diverse communities that are expected to have a variety of responses to climate change. While some are dependent on moisture and may be harmed, others may actually benefit from increased drought and fire. This benefit will only be realized if sites are protected from other forms of destruction, and for most, if fire is restored to them through prescribed burning. These communities are naturally rare in North Carolina, due to limited availability of suitable habitat. Examples need to be protected and managed appropriately. Some climate change models predict that rainfall will be concentrated during the fall, and there will be increased droughts in the spring and summer. Droughts could favor herbaceous species and grasses in open, dry outcrops, which tend to be rarer than the woody species associated with outcrops. Drought will kill trees on edges and soil islands. This already happens in current droughts and is part of the mechanism keeping flatrocks open. Increased length or severity of droughts might cause flatrocks to expand at the expense of adjacent shallow-soil woodlands. Herb species associated with granitic flatrocks tolerate drought at present or grow in the moist early growing season. It is unclear if they are at the margin of their tolerance, or whether they could withstand longer or more severe droughts. Drought in spring would be detrimental, while drought in other seasons might not be. A few additional flatrocks may be opened up by wind throw or drought mortality. Increased storms may blow down trees and pull up soil mats more frequently. The amount of bare outcrops and shallow soil mats may increase at the expense of deeper mats. Increased temperatures could increase demand for water, a limited resource in these sites. Phenological shifts (earlier bloom periods, emergence from hibernation, nesting and breeding) in seasons may occur in a warmer climate. Exotic plants readily invade favorable microsites on many outcrops. Increased disruption of adjacent forests may bring seed sources closer to many outcrops. Development. As with high-elevation rock outcrops, two major problems most associated with the low-elevation rock outcrops include development and recreational impacts. However, low- elevation rock outcrops are subjected to short-term habitat alterations (e.g., forestry operations) more often than high-elevation rock outcrops due to land ownership patterns, proximity to markets, accessibility, and other factors. The extent and degree of impact associated with such temporary alterations are unclear for most species. Regardless of the impacts or problems associated with short-term habitat modifications, the relative scarcity of low-elevation rock outcrop habitat across the landscape of North Carolina and reliance upon it
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2025 NC Wildlife Action Plan
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