4.4 Terrestrial Communities
4.4.8.3 Problems Affecting Habitats Conditions vary considerably within this habitat type, with a signifcant number having been impacted and/or lost due to numerous factors, while others remain functional “natu- ral sites” and still others are specifcally managed to minimize human impacts. Low-elevation clifs 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 beneft from increased drought and fre. Tis beneft will only be realized if sites are protected from other forms of destruction, and for most, if fre is restored to them through prescribed burning. Tese communities are naturally rare in North Carolina, due to limited availability of suitable habitat. Examples need to be pro- tected and managed appropriately. 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. Te extent and degree of impact asso- ciated with such temporary habitat alterations is unclear for most species. Regardless of the impacts or problems associated with short-term habitat modifcations, the relative scarcity of low-elevation rock outcrop habitat across the landscape of North Carolina, and reliance upon it by numerous wildlife species lends greater signifcance to the need to identify and manage these habitats appropriately to conserve wildlife. 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 herba- ceous 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. Tis already happens in current droughts, and is part of the mechanism keeping fatrocks open. Increased length or severity of droughts might cause fatrocks to expand at the expense of adjacent shallow-soil woodlands. Herb species associated with granitic fatrocks 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 fatrocks may be opened up by wind throw or drought mortality. Increased storms may blow down trees and pull up soil mats more frequently. Amount of bare out- crop and shallow soil mats may increase at the expense of deeper mats. Low intensity fres could expand the open area and beneft some of the rare plants of out- crops. More mesic outcrops such as heath bluf communities are more likely to be harmed by fre. Landscape fragmentation and fre suppression practices likely will continue to
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2015 NC Wildlife Action Plan
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