Chapter 3 North Carolina Species
3.10.1.1 Aquatic Insects Inland freshwater covers a very small percentage of the Earth’s surface, but it provides habitat to almost 100,000 insect species from at least 12 orders that have one or more life stages in freshwater. Aquatic insects spend one or more stages of their life cycles in the water, with the majority living in water as eggs and larvae before maturing into adults and moving to terrestrial habitats. Nearly half of all aquatic insects considered to be true flies (order Diptera ) are almost exclusively restricted to freshwater by an aquatic larval stage, as are Mayflies, Stoneflies, Caddisflies, Dragonflies, and Dobson flies (order Megaloptera ) (Suter and Cormier 2014) . Often the aquatic larval stage lasts significantly longer than the terrestrial adult life stage (e.g., mayflies). Their ecological roles as primary consumers, detritivores, predators, and pollinators have an important influence on both terrestrial and aquatic communities, and they can serve as bioindicators of natural community health (Suter and Cormier 2014) . Aquatic insects are a primary food resource for many fish and crayfish species. As they emerge from aquatic larvae to adult insects and disperse to surrounding areas, they become an important prey resource for terrestrial wildlife (i.e., birds, bats) that forage in riparian areas. 3.10.1.2 Terrestrial Insects The largest number of insects worldwide are wholly terrestrial species (Deutsch et al. 2008) that have defined life cycle phases and specific foraging requirements for each stage. For instance, insect herbivores and pollinators are likely to have life cycles synchronized to plant phenology. For pollinators such as butterflies and moths this can be crucial (e.g., monarch caterpillars and availability of milkweed) as development outside the period of optimal conditions can have severe fitness consequences for both the insect (missed food resource) and plants (missed pollination, lack of seed set) (VanAsch & Visser 2007, Cornelissen 2011) . An estimated 80% of wild plants depend on terrestrial insects for pollination (Ollerton et al. 2011) , while 60% of birds rely on terrestrial insects as a food source (Morse 1971, Hallmann et al. 2017) . Most insects are ectotherms, meaning they rely on external sources for temperature regulation. Given that thermoregulation is important for activity and survival for ectotherms (Heinrich 1996, Deutsch et al. 2008) , temperature is likely an important mechanism influencing terrestrial arthropod communities at multiple scales (i.e., climatic, altitudinal, latitudinal) and social structures (i.e., colonial species) (Abram et al. 2017, Wong et al. 2019) . North Carolina’s climate is typically humid and temperate, and insects are likely to benefit from warming trends and the increase in number of excessive heat days. 3.10.2 Conservation Concerns Decline of insects has been increasingly reported worldwide over the last few decades (Dirzo et al. 2014; Hallmann et al. 2017, Homburg et al. 2019, Orr et al. 2021) . Invertebrates often have highly specific habitat requirements, much more than is typical for vertebrates. Many insects, for example, have larvae that feed only on a particular host plant. Habitat requirements for these species include host plants as well as habitats for adult insects. In addition to those considered critically
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2025 NC Wildlife Action Plan
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