Muskrat Ecology in Old Crow Flats, Yukon, 2007-2010

To gain better insight into the factors responsible for among lake variation in muskrat abundance in the Old Crow Flats, we will study muskrats on as wide a range of lakes across the Flats as possible. Lake-to-lake variation in muskrat abundance will be estimated with aerial surveys of muskrat push-up density. The abundance of aquatic vegetation, as well as lake hydrological and limnological characteristics, will be documented for a subset of surveyed lakes in collaboration with other researchers involved in the project. Then, working in collaboration with Vuntut Gwitchin trappers we will obtain muskrat carcasses or selected tissues from some study lakes. Analysis of carcasses, which will be performed at McGill, the laboratories of collaborating researchers, and/or commercial labs, will involve estimation of 1) age and body size, 2) diet composition via stable isotope analysis and/or stomach content analysis, and 3) gene flow between study lakes based on microsatellite genetic markers.