Cat de Rivera
Date of Award
Bachelor of Science (B.S.) in Environmental Science and University Honors
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.
Krige, Rodé, "How Beavers (Castor canadensis) Affect Habitat Availability for Two Native Oregon Turtles: Actinemys marmorata and Chrysemys picta bellii" (2023). University Honors Theses. Paper 1413.