2007 Summaries of Wildlife Research Findings - Minnesota State ...

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southeastern Minnesota and the North Shore where topographic relief is relatively pronounced,
north slopes may act as refugia, allowing individuals and populations to remain in suitable
microclimates by moving from south to north slopes.
Genetic adaptation in response to warming temperatures has been demonstrated by some
species (Nowak et al. 1994, Hughes 2000) and depends on generation time as well as adequate
levels of genetic variation within and among populations (Noss 2001). Species whose range and
populations increase under climate change, such as many insects, may adapt well. For other
species, however, genetic adaptation will be limited by anticipated declines in abundance and
genetic variation as a consequence of selection imposed by climate change (Noss 2001).
Some wildlife species are distributed throughout most or all of Minnesota (Appendix A).
These habitat generalists will be affected by climate change, but the effects may be less severe or
more difficult to monitor than effects on species that are habitat specialists. Many habitat
generalists demonstrate great adaptability to different levels of human development, including
urban landscapes. Some of these species, however, may require management attention if climate
change causes their populations to exceed acceptable levels. For example, managing whitetailed
deer populations within goals will continue to be important (scientific names are provided
in Appendix B). Survival of white-tailed deer is related to the frequency and severity of winter
weather (DelGiudice et al. 2002) and could increase due to climate change. Impacts on deer may
depend on specific moisture regimes. For example, increased winter precipitation may cause
deeper snow pack, which reduces deer survival. As a large herbivore, deer have the potential to
impact plant communities and species diversity. Over-wintering populations greater than 9.7–
13.5 deer/mi 2 (25–35 deer/km 2 ) in fragmented forests result in local extirpation of trillium and
other understory forbs and inhibit plant and forest restoration efforts (Augustine and Frelich
1998).
3.1.2. Biodiversity and new biological communities
Moisture, minimum and maximum temperatures, soils, and length of the growing season
largely determine the composition and distribution of biological communities in Minnesota.
Natural and human-induced disturbance regimes also influence our present and future natural
environment.