Hydrologic change and muskrat population dynamics in the Peace-Athabasca Delta, Canada
Abstract/Contents
- Abstract
- Empirical and anecdotal reports suggest that muskrat are in decline across North America, including in the 5500 square km Peace-Athabasca Delta ("Delta"), Canada, part of a World Heritage Site with 'in Danger' status pending. This dissertation is concerned with the effects of rapid hydrologic change on the Delta's muskrat population. Analysis of a Landsat-derived record of inundation for the Delta (1972-2017), together with 21 years of muskrat survey records, show that the catastrophic decline in the Delta's muskrat population is synchronous with loss of critical habitat. Results suggest that loss of wetland habitat could be the cause of the observed, but as yet unexplained, decline of muskrat across North America. Conceptual and quantitative agent models of the muskrat population at a model floodplain lake region of the Delta illustrate mechanisms controlling muskrat abundance. Model results show that shoreline habitat and muskrat intensive herbivory are key mechanisms controlling muskrat abundance, while trapping intensity is not a primary factor. This is a key finding as muskrat trapping continues to be an important practice for Indigenous communities with traditional territory in the Delta. Ecological agent modeling, dynamic habitat maps driven by hydrologic change, and landscape genetic analysis are brought together to assess spatio-temporal characteristics of population dynamics for muskrat on the Delta floodplain. Results show that the Delta undergoes dramatic transitions from a network of population sources, to a network of population sinks, on an interannual basis in years following floodwater inputs. Notably, this network of sources and sinks is less prominent following the most recent flood in 2014, suggesting a reduced footprint of the muskrat population on the Delta floodplain, a change with broad implications for the ecological integrity of the Delta ecosystem. Together, the findings from this dissertation lay the groundwork for use of muskrat as an indicator species for the impacts of hydrologic change on wetland ecosystems, particularly in subarctic and arctic delta regions where the hydrologic effects of climate change are pronounced.
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource. |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2019; ©2019 |
| Publication date | 2019; 2019 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Ward, Ellen Marguerite |
|---|---|
| Degree supervisor | Gorelick, Steven M |
| Thesis advisor | Gorelick, Steven M |
| Thesis advisor | Hadly, Elizabeth Anne, 1958- |
| Thesis advisor | Lambin, Eric F |
| Degree committee member | Hadly, Elizabeth Anne, 1958- |
| Degree committee member | Lambin, Eric F |
| Associated with | Stanford University, Earth Systems Science. |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | Ellen Marguerite Ward. |
|---|---|
| Note | Submitted to the Earth Systems Science. |
| Thesis | Thesis Ph.D. Stanford University 2019. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2019 by Ellen Marguerite Ward
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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