Article Abstract:
Mixed-conifer forests in the Bear Valley National Wildlife Refuge, OR, are important roost sites for some over-wintering bald eagles, but past fire suppression and logging activities have caused a decline in the roost environment. A new study examines the use of roosting sites by bald eagles with reference to the attributes of roosting trees, vegetation surrounding roost trees and characteristics of subroosts. Results suggest that roost suitability in the refuge is declining because of shifts in tree composition. Recommendations for improving roost composition include prescribed fire, seeding with roost trees and limited thinning.
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Article Abstract:
The reliability of jackknife estimators in determining the population of animals with low-capture probabilities is investigated using capture-recapture data on Oregon's northern flying squirrel. The evaluated estimators include the jackknife estimator selection method, the higher-order jackknife estimator and the moment estimator. In addition, Monte Carlo simulations were performed. They verified the obtained estimates with empirical data collected from the field.
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Article Abstract:
Research undertaken in the central Oregon Cascades in the Willamette National Forest near Blue River and McKenzie Bridge, OR, into movements of northern flying squirrels indicates that male flying squirrels use larger home ranges than females. However, movements between successive locations did not differ between male and female flying squirrels. Stand type did not affect home range size or flying squirrel movements between successive locations.
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