This work is done in conjunction with our moose and white-tailed deer monitoring to understand the invasion ecology of deer as it relates to change in the boreal forest. Our goal here is to understand local-scale potential for apparent competition between moose and deer as mediated by disturbance, predation, and pathogens. With our partners, we will further advance Indigenous-engaged CWD surveillance (sample collection, led by Dr. Abdullah-al Mamun; testing in collaboration with the lab of Dr. Sabine Gilch, University of Calgary); and modelling of the transmission ecology of CWD in the mid-boreal with respect to deer, moose, and caribou based on movements and habitat use, carrier genetics, gene-flow, and landscape resistance. The latter will be led by new graduate student Ms. Laura Dyson, who will begin her M.Sc.-Ph.D. transfer program in September 2024, with field work commencing as a research assistant in summer 2024. Ms. Ayicia Nabigon (M.Sc. USask Biology) will initially be comparing resource selection functions of white-tailed deer (building on the M.Sc. work of Dale Barks, USask Biology) and moose overlapping in home ranges to identify seasonal potential for meningeal worm (and CWD) spread into moose. Mr. Dale Barks is scheduled to defend his M.Sc. thesis on the topic later in 2024.
The transmission of CWD into boreal caribou, should it occur, would be a landmark event in the history of boreal caribou conservation in Canada. Our research activities are taking place where invasive and infected white-tailed deer are now known to be sharing range with boreal caribou, in the Torch River area of the SK2 Central and SK2 East Boreal Caribou Units; and as far north as La Ronge, SK, where we have tracked deer summering in caribou range that have visited known sites of horizontal transmission of CWD. While our work for this project has confirmed that CWD-infected deer now range into the SK2 caribou range (GPS-collar tracking by M.Sc. student Dale Barks), at this time we do not know the actual risks of CWD transmission to caribou. Our objective here (led new graduate student Laura Dyson) will be to develop a transmission-risk model for caribou based on the expected probabilities that boreal caribou will encounter sites where infected deer have visited, persistence probability of infective CWD prions in soils of the boreal forest at these sites, current instances of infection in cervids of the SK2 range, and projections of spread if CWD transfers into boreal caribou. For this work, we will be deploying an array of camera-traps along known routes deer have used (based on our a priori knowledge of boreal-deer resource selection, from our 3-years of GPS-tracking data), to document times and seasons where deer and caribou have overlapped in space. Sampling for prions in soils and feces along such routes will help us to estimate probabilities of transmission. While the transmission rate can confidently be predicted now as being greater than zero (moose, e.g., have acquired CWD from deer through this route of transmission), informed management actions will require estimates of actual transmission probabilities. Funding for this part of our NSERC program was recently given a boost by the awarding of $90,000 from the Saskatchewan Ministry of Environment in April, 2024.