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Tritrophic Interactions In Forests: Direct And Indirect Interactions Between Birds, Insect Herbivores, And Oaks, Nicholas Anthony Barber

Dissertations

This study examines direct and indirect relationships between three trophic levels to determine effects on plant damage, herbivore abundance and community structure, and bird distribution in forest ecosystems. Exclusion experiments on white oak (Quercus alba) revealed that bird predation effects to not vary spatially despite variation in abundance of both birds and insects. Using a leaf quality manipulation, I demonstrated that bird impacts do not differ with host plant quality. Rather, birds and plant traits had additive effects on herbivore damage. Bottom-up effects of leaf quality were also more important than top-down effects of birds in structuring the insect herbivore …