Suitable habitat for northern species will decline in the Central Appalachians.

Submitted by dshannon on

"Across northern latitudes, past periods of warmer temperatures have resulted in species’ distribution changes toward the north and also upward in elevation. The ranges of eastern hemlock and red spruce lay largely to the north of the Central Appalachians, but these species currently persist in microhabitats that remain cool and moist enough to support them. Red spruce is more limited within the Central Appalachians, occurring at high elevations in the Allegheny Mountains section of West Virginia. Hemlock is more widespread, occupying cool and wet sites at lower elevations. As these species’ ranges continue to shift northward, they may become rare or extirpated from the area. In the absence of other mortality agents, long-lived individuals already established in cool, wet microhabitats may persist for many years, even when habitat becomes unsuitable for regeneration or growth. Due to the geographic limitations of their current habitat, these species are unlikely to migrate even if newly suitable habitat became available elsewhere. Results from climate impact models also suggest declines in suitable habitat for northern species that are not so geographically limited, such as sugar maple. These species near the southern edge of their range may also be able to persist in southern refugia if potential new competitors from farther south are unable to colonize these areas, although they are expected to have reduced vigor and be under greater stress."