First Advisor

Cat de Rivera

Date of Award

Fall 12-2023

Document Type


Degree Name

Bachelor of Science (B.S.) in Environmental Science and University Honors


Environmental Science




beaver, pond turtle, painted turtle, habitat, Portland, Oregon




Oregon is home to two native freshwater turtle species: the northwestern pond turtle and the western painted turtle. Both turtles are Oregon conservation strategy species with a status rating of sensitive, indicating declining populations. Oregon’s decline in these turtle’s populations is thought to be predominantly due to loss and degradation of habitat that results from development and urbanization. Beavers’ ability to dam streams and create ponds may be creating habitat usable by turtles, but the relationship is under-studied. This study assessed water temperature, basking habitat, and overall turtle habitat suitability at beaver-dammed and control ponds in Portland, Oregon. Average basking habitat and turtle habitat scores were higher in beaver-dammed ponds than in control ponds. Water temperature showed trends of higher variability in beaver-dammed ponds than in control ponds. These results provide support for the potential mechanisms behind how the act of beavers damming could create beneficial habitat for native freshwater turtles in Oregon. Suggestions for future research include focusing on other turtle habitat requirements such as nesting habitat, juvenile habitat, and over-wintering habitat.

Persistent Identifier