Browse history as an indicator of snowshoe hare response to silvicultural practices adapted for old-growth boreal forests

Abstract

We used browse history surveys of paper birch (Betula papyrifera) to evaluate the response of snowshoe hare (Lepus americanus) to harvest treatments with 0–70% tree retention in boreal forests of eastern Quebec. The proportion of different birch stem architecture types was used to assess broad changes in browsing pressure following harvesting. We also identified the years in which individual birch stems were browsed by hares to compare probability of stem use over time, from the winter preceding harvesting until 2–3 y after logging. A higher proportion of birch with released-type growth forms in logged stands suggested a reduction in browsing by hare following all types of harvest treatment. Detailed stem analysis revealed, however, that changes in browsing pressure varied considerably among treatments. Hares browsed individual stems with equal probability in all sites prior to harvesting. Probability of stem use declined rapidly in treatments with < 25% tree retention (basal area ≤ 3 m2.ha−1) relative to uncut forests in the 2–3 y following harvesting. In contrast, birch stems in selection cutting treatments with > 50% tree retention (basal area ≥ 15 m2.ha−1) remained just as likely to be browsed by hare as those in uncut forests during the same period. Browse history provided a unique opportunity to assess pre-treatment habitat use, even though surveys took place after logging. Selection cutting appears to be a promising avenue for maintaining snowshoe hare habitat that is characteristic of old-growth eastern boreal forests, even over the short term.