impact of alternative harvesting practices on the small mammal community in an ontario boreal mixedwood forest
abstract
during the current project four studies were conducted to determine the effect of alternative
silvicultural systems, and harvesting methods on the small mammal community of a boreal
mixedwood forest in northern ontario. in the first study (chapter 1) pitfall and livetrapping
were used to monitor the small mammal community in uncut forest, on lands harvested under the
clearcut and shelterwood silvicultural systems, and at the edge of these harvest treatments.
livetrapping was used during the second study (chapter 2) to monitor the effect of different
harvesting methods on the small mammal edge community of clearcut and shelterwood cut
areas. the third study (chapter 3) investigated how small mammals used the treated and
untreated side of livetrapping grids at the edge of all six timber harvest treatments, and in uncut
forest. finally, during the fourth study (chapter 4) radio-telemetry was used to investigate the
response of peromyscus maniculatus (deer mice) to several timber harvest treatments.
differences in the small mammal communities associated with the harvest treatments were
noted during all four studies. for instance, the first study revealed that the number of clethrionomys
gapperi (southern red-backed voles) was lower, and the number of glaucomys
sabrimis (northern flying squirrel) captures was higher at clearcut edges than at shelterwood
edges and in controls by the second year after timber harvest. the second study found a higher
number of g. sabrinus captures at the edge of full-tree clearcuts than at tree-length clearcuts
and on controls in the second post-harvest year. the third study revealed that c. gapperi and
p. maniculatus utilized harvested edges differently. and the fourth study revealed differences in
the way habitat was used by p. maniculatus on clearcut, shelterwood, and control treatments.
these studies revealed that applying different silvicultural systems and harvesting methods
can influence the small mammal community. since small mammal species responded to the
harvest treatments differently, it follows that foresters will need to implement a variety of silvicultural
systems and harvest methods within boreal mixedwood forests if conservation of small
mammal species diversity in these areas is of concern. some species, such asphenacomys
intermedius (heather voles), sorex hoyi (pygmy shrews), and glaucomys sabrinus, were
more common in this mixedwood forest than expected so they could be of particular importance
in boreal mixedwood management
the variability in species abundance observed among the replicates used during this work
demonstrates the importance of replicating the timber harvest treatments being investigated
during such projects. the conclusions from this research could have been much different if
treatments had not been replicated. also demonstrated was the importance of using several
different trapping methods when assessing the abundance, richness, diversity and composition of
small mammal species in a community as some species were captured by only one trapping
method during this project.
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- retrospective theses [1604]