3.12 Insects
desired outcome. He presents fve “rule-of-thumb” generalizations that may be a frst-step toward more comprehensive management of natural areas and ecological preserves in North Carolina. Insects and other invertebrates may respond to certain management practices very difer- ently than plants or vertebrates; gauging the success of management by the efects on those species may miss signifcant damage being done inadvertently to insects and other nontar- get species. Tis is particularly true for prescribed burning. Te NCNHP has developed a set of guidelines for conducting burns in ways that minimize impacts to rare insect popula- tions (Hall and Schwietzer 1993; Hall 1999a) . If ecosystem-level conservation planning is to succeed, managers must include inverte- brates in site management considerations (Hall 1999a) . Te following passages, which were included in the 2005 WAP and remain appropriate, are excerpted from Hall (1999a) . Rule of Tumb 1. Management actions that signifcantly alter some aspect of an ecosystem are likely to have major efects on insects and other invertebrates. Te responses of these species to the management actions may be very diferent than those of plants or vertebrates, the usual intended benefciaries of the action. In the worst case, a large number of the unknown but important “cogs and wheels” of the ecosystem may be lost as a result of the action. Keeping this in mind, additional rules of thumb will be described below that can help reduce the likelihood of a dire outcome. Nature preserves, including most state parks, are usually established where high-quality examples of native ecosystems exist, as indicated by vegetative commu- nities or the presence of rare species of plants or vertebrates. Although few preserves have yet been created specifcally with insects or other invertebrates in mind, areas of high-quality native habitats usually contain signifcant faunas of invertebrates as well. Tere are, in fact, several reasons why invertebrates frequently are among the rarest species in a given preserve. Rule of Tumb 2. Te larger landscape is important in the conservation of insects and other inverte- brates. When natural landscapes are replaced with a mosaic of small patches of native habitats in a matrix of lands converted to human uses (habitat fragmentation) all spe- cies are afected. Fragmentation reduces the overall amount of available habitat, involv- ing outright losses as well as more subtle reductions due to edge efects. Te most severe efects, however, may be on species critically dependent on metapopulations structures.
By defnition, habitat fragmentation is a process that increases the distances between suitable habitat patches and therefore increases the difculties or outright danger to
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2015 NC Wildlife Action Plan
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