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advantage over many native species that are also shifting ranges because most invasive species have rapid dispersal abilities and may have the capac- ity to survive and tolerate a range of environmental conditions (Dukes and Mooney 1999). In British Columbia, warmer temperatures are implicated in expanded large mountain pine beetle (Dendroctonus ponderosae) outbreaks that are now occurring further north than they have previously been recorded (Logan et al. 2003). The hemlock woolly adelgid (Adelges tsugae) is an invasive non - native insect likely to expand as a result of climate change ( Paradis et al. 2007). Hemlock wooly adelgid has had a catastroph- ic impact on the forest system of the eastern U.S. by decimating stands of eastern and Carolina hemlock (Tsuga canadensis and T. caroliniana). The adelgid is sensitive to cold temperatures and experiences great- er overwintering mortality when exposed to colder conditions for longer periods of time (Shields and Cheah 2004, Paradis et al. 2007). Although the first known hemlock infestation was found in Virginia in 1951, this invasive pest has already spread to signifi- cant portions of the eastern U.S. since (USDA Forest Service 2010, Figure 1 -5). Historic rates of spread indicate an outward expansion of the hemlock woody adelgid's range from its current known range. However, this estimation does not include the predicted impacts of increasing temperatures on its range (Figure 1 -6). The ability of native and non - native species to shift in response to climate changes will depend on a number of factors, including the species' ability to keep pace with climate change through dispersal, the availability of suitable habitat, the permeability of the landscape through which the species must move, the species' capacity to adapt to change, and the resulting interactions of the species within a new community. Coupled global climate models and global vegeta- tion models suggest that keeping pace with climate change may require migration rates much faster than those observed during post - glacial times, potentially at rates of 1,000 meters per year or more (Malcolm et al. 2002). As the geographic range and timing in more, l'C'lcvemt in t �� e' U'; "'oI'/te' „x "t ,l rcs'Ponse,S to of species migration changes, there is also potential for mismatches between species and the resources they require to survive. Furthermore, highways and expanding urban areas, as well as the often isolated distribution of protected areas, may prevent species from successfully migrating in response to climate change. 7_2_2 2_2 CIIrriat f' ( "'w e,,,Iii li aI`;r° Ilitel;°act/i'lrls Species have evolved within an ecological context and are therefore tightly linked to the abiotic and biotic components of ecosystems. The influence of climate on the ecology of species includes direct constraints on the physiology of organisms, as well as indirect effects resulting from disruptions to food supply, changes in competitive interactions, or influ- ences on behavior, along with many others (McCarty 2001, Walther et al. 2002, Parmesan 2006). Any one of these effects alone or in combination has the potential to impact reproduction and /or survival, and therefore the long -term viability of popula- tions. There is now ample evidence for the ecological