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AbstractOvenbird (Seiurus aurocapilla) demography and nest-site selection were examined in mature tolerant hardwood stands and stands at 3 stages of recovery (1–5, 10–15, and 20–25 y) following single-tree selection in the continuously forested landscape of Algonquin Provincial Park, central Ontario. This is one of a few studies to provide evidence of these responses in a continuously forested landscape. No differences in nesting success or finite rates of increase were detected among treatments. Ovenbirds were more selective of nest sites with deep leaf-litter and basal areas with a greater proportion of larger trees in recently harvested stands than in other stages of recovery. By 20–25 y post-harvest, most nest-site and random-plot microhabitat parameters did not differ. During the study, Algonquin Provincial Park was designated as a sink, probably due to heavy mast production in 2006, after which some mast-consuming small mammal populations increased by 9-fold, dramatically increasing rates of nest predation. Single-tree selection did not appear to affect ovenbird per capita productivity among stages of forest recovery, and by 20–25 y post-harvest many structural features of the forest had returned to pre-harvest conditions. Thus, in Algonquin Provincial Park, single-tree selection appears to be appropriate for maintaining sufficient ovenbird nest-site features by the end of the first cutting cycle. However, future source-sink modeling of this landscape should consider the influence of resource-pulse dynamics as an important parameter and track changes over the long term, to determine how sustainable populations of ovenbirds are within this region.

AbstractWe compared temporal changes in composition and abundance of ground beetles (Carabidae) among hardwood forest stands that underwent single-tree selection cutting 0.5-3 years previously, 15-20 years previously, and reference stands that are and will remain unmanaged in the park’s wilderness zone to determine impact of this silvicultural method on these important invertebrates. Short-term (0.5-3 year post-logging) effects included an increase in the number of forest generalist and open habitat species, a loss of large bodied species, and substantial (> 50%) reductions in activity densities of carabids; the latter effect correlated with significant reductions in leaf litter. Long-term (15-20 year post-logging) effects included an increase in forest generalist and open habitat species and increases in the activity densities of a few species that preferred the vegetation characteristics present in the 15-20 year treatment and absent from reference stands. Beetle communities in stands harvested 15-20 years previously contained activity densities and species composition similar to reference stands in the park, suggesting few long-term effects after the first rotation of this method. Introduced carabids were rare in our mostly forested study area. We recommend examining effects of a second rotation on carabid communities.