RETURN TO THE FLOODPLAIN: THE ROLE OF BEAVERS (CASTOR CANADENSIS) IN RESTORING CHANNEL COMPLEXITY AT WASSON CREEK
| dc.contributor.author | Marshall, Sarah Marie | |
| dc.date.accessioned | 2020-04-29T21:36:55Z | |
| dc.date.available | 2020-04-29T21:36:55Z | |
| dc.date.issued | 2004-08 | |
| dc.description | 101 pages. A thesis presented to the Department of Environmental Science and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2004. | en_US |
| dc.description.abstract | Beavers (Castor canadensis) are a keystone species capable ofrapidly altering habitat and hydrologic conditions in aquatic ecosystems. At Wasson Creek, a degraded stream in the South Slough National Estuarine Research Reserve, beaver activity may be able to restore channel complexity. To evaluate current conditions and the influence of beavers at Wasson Creek, I recorded stream stage in high and low beaver activity areas relative to a range of precipitation events, measured stream channel patterns and the fate of over-bank flow on the floodplain, mapped change in the original agricultural ditch through time, and monitored beaver activity. During the study, Wasson Creek over-topped the banks of the main channel at the two stage- recording sites in response to a 6-10-year storm event. Following the event, the floodplain above the two largest beaver dams and around dams in a shallower, narrower secondary channel remained inundated for most of the study period. Despite minimal change in the path and sinuosity of the main channel over 65 years, beaver activity has altered water movt:ment on the floodplain-particularly in areas where beaver dams cross the floodplain, beavers excavated channels on the floodplain, and flows were re-directed into a smaller, secondary drainage ditch. Given the high level of beaver activity on the floodplain (17 actively maintained dams) and suitable habitat, we can expect beavers to remain in the system- further creating a new complex of channels and wetlands on the Wasson Creek floodplain. Human intervention may be necessary to control reed canary grass (Phalaris arundinacea) and other invasive species. | en_US |
| dc.identifier.uri | https://hdl.handle.net/1794/25341 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | University of Oregon | en_US |
| dc.relation.ispartofseries | University of Oregon theses, Dept. of Environmental Science, Honors College, B.S.,;2004 | |
| dc.rights | Creative Commons BY-NC-ND 4.0-US | en_US |
| dc.rights | UO theses and dissertations are provided for research and educational purposes, and may be under copyright by the author or the author’s heirs. Please contact us <mailto:scholars@uoregon.edu> with any questions or comments. In your email, be sure to include the URL and title of the specific items that you are inquiring about. | |
| dc.title | RETURN TO THE FLOODPLAIN: THE ROLE OF BEAVERS (CASTOR CANADENSIS) IN RESTORING CHANNEL COMPLEXITY AT WASSON CREEK | en_US |
| dc.type | Thesis / Dissertation | en_US |