Honors Theses


Ryan McEwan



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Honors Thesis


Invasive species can disrupt ecosystems and negatively affect other species. Callery pear (Pyrus calleryana) is an invasive ornamental tree that is spreading quickly throughout the United States. It is possible that birds are responsible for spreading Callery pear by eating the fruit and depositing seeds in new areas. European starlings (Sturnus vulgaris) and American robins (Turdus migratorius) are mentioned in most studies as responsible for the dispersal of Callery pear. However, there is also evidence that Cedar waxwings (Bombycilla cedrorum) also feed on the tree. Invasive plants can impact avian health, reproduction, and migration. Additionally, there are many aspects of bird dispersal to understand in order to see the full picture of the mutualism between birds and Callery pear. There is little research done on the interactions between birds and Callery pear despite them having such an important relationship. This review aims to identify gaps in the scientific literature on this topic and future research needed. A pilot study survey was completed to better understand bird and Callery pear interactions. The ideas discussed in this study will be useful to future ecological research focusing on invasive plant and bird interactions. Furthermore, this research will aid management decisions regarding Callery pear.

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This item is protected by copyright law (Title 17, U.S. Code) and may only be used for noncommercial, educational, and scholarly purposes.


Undergraduate research



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