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Concern over global environmental change and associated uncertainty has given rise to greater emphasis on fostering resilience through forest management. We examined the impact of standard silvicultural systems (including clearcutting, shelterwood, and selection) compared with unharvested controls on tree functional identity and functional diversity in three forest types distributed across the northeastern United States. Sites included the Argonne, Bartlett, and Penobscot Experimental Forests located in Wisconsin, New Hampshire, and Maine, respectively. We quantified functional trait means for leaf mass per area, specific gravity, maximum height, height achieved at 20 years, seed mass, drought tolerance, shade tolerance,...
To investigate whether Northern Goshawk textit(Accipiter gentilis) reproduction is food-limited, we evaluated the reproductive output from 401 goshawk breeding opportunities on the Kaibab Plateau, Arizona during 1999-2002. Concurrently, we estimated densities of 10 goshawk prey species (seven birds, three mammals) using distance sampling. We then assessed the relationship between goshawk productivity (number of fledglings produced) and prey density within and among years by relating the contribution of individual prey species and total prey density to goshawk productivity. We also estimated the proportion of total diet and biomass for each species that contributed ?3% of all prey items. Total prey density was highly...
Introduction : Swainson’s Thrush is a medium sized (15-18cm) thrush which prefers to breed in dense shrub growth associated with spruce-fir forests. The "russet-backed" race prefers mixed forests and deciduous riparian woodlands of the coastal region from British Columbia, to northern California. These Pacific populations winter in mature tropical and secondary forests of Central America, whereas the "olive-backed" race that breeds in the Boreal and Rockies winters in S. America. Models of Monitoring Avian Productivity and Survival (MAPS) demographic data and high-resolution land cover data showed that Swainson’s Thrush prefers large intact forest patches with low perimeter to area ratios. On a regional...

map background search result map search result map Swainson's Thrush - Predicted Productivity Index Swainson's Thrush - Predicted Productivity Index