Hydrology and Muskrat Population of the Peace-Athabasca Delta, Canada

Project Leads

• Ellen Ward
• Steven Gorelick

Introduction  
For this project, we are building a conceptual and quantitative modeling framework (Fig. 1) linking climate change, upstream water demand, and hydrologic change in the floodplain of the Peace-Athabasca Delta to muskrat (Ondatra zibethicus) population dynamics, with the objective of exploring the impacts of these stressors on this ecosystem. The 6000 km² Peace-Athabasca Delta (“Delta”) in northeastern Alberta, Canada, is a Ramsar Convention Wetland and UNESCO World Heritage Site (“in Danger” status pending) where hydropower development and climate change are creating ecological impacts through desiccation and reduction in Delta shoreline habitat. Muskrat are a species native to the Delta, whose populations are highly responsive to changes in floodplain hydrology, are readily monitored, and that have tremendous cultural importance both locally and throughout northern Canada and Alaska. Muskrat have sustained subsistence and commercial trapping by Aboriginal and non-native residents of the Delta for centuries.

Our research goals include

• Developing a quantitative model of muskrat demography informed by Delta-wide, dynamic habitat suitability maps that are shaped by floodplain hydrology. The Peace-Athabasca Delta Ecological Monitoring Program (PADEMP) is generously sharing their muskrat population survey results with us for the development of the muskrat population model.
   
• Using muskrat genetic information to constrain our simulation of population changes in the quantitative ecohydrologic model. Genetic analysis of the Delta muskrat population will be carried out by our collaborators in the Hadly Lab in Stanford’s Biology department. Muskrat tissue samples are being donated by trappers based out of Fort Chipewyan, and brought together thanks to our collaborators at the Fort Chipewyan Parks Canada office and to assistance from the GIR office of the Mikisew Cree First Nation.
   
• Placing local traditional knowledge of Delta muskrat in direct conversation with our western scientific findings, through collaborations with several Aboriginal communities that trap Delta muskrat. TK about Delta muskrat will inform our representation of trapping in the quantitative model, and will provide independent narratives of hydrologic and ecological change witnessed by trappers over decades spent out on Delta lakes.
   
• Bringing together the quantitative ecohydrologic model, genetic analysis, and traditional knowledge to identify water management scenarios that mitigate the impacts of climate change and upstream water demands on Delta floodplain lakes, muskrat and Aboriginal treaty rights to subsistence trapping.

Publications 
Ward, E.M., K. Wysong, S.M. Gorelick, (2019), Drying landscape and interannual herbivory-driven habitat degradation control semi-aquatic mammal population dynamics, Ecohydrology, doi.org/10.1002/eco.2169

Ward, E.M. and S.M. Gorelick, (2018), Drying drives decline in muskrat population in the Peace-Athabasca Delta, Canada, Environmental Research Letters,13 (2018) 124026, doi.org/10.1088/1748-9326/aaf0ec.