Midwest Fish & Wildlife Conference 2017

AUTHORS: Ryan G. Tebo, Farmland Wildlife Populations and Research Group, Minnesota Department of Natural Resources

ABSTRACT: Hunters in Minnesota have recently voiced concerns that squirrel populations are in decline (due to overharvest and liberal hunting regulations), namely on public hunting lands within travel distance of the St. Paul-Minneapolis metropolitan area.  To address these concerns, the Minnesota Department of Natural Resources began a 2-year study comparing survival rates of squirrels on a wildlife management area where hunting is permitted and at a nearby state park where hunting is prohibited.  We captured and radiocollared 49 gray and 7 fox squirrels at Whitewater Wildlife Management Area (WMA) and 49 gray squirrels at Whitewater State Park (SP) during July-September 2015.  Squirrels were monitored for survival following capture and survival rates were estimated by site and season using logistic-exposure methods.  During the first field season, we failed to find evidence that survival probabilities differed between sites prior to the hunting season  (1 July – 18 Sep 2015) and after the first 6 weeks of the hunting season (1 Nov 2015 – 12 April 2016).  However, during the first 6 weeks of the hunting season (19 Sep – 31 Oct 2015), 13 of 44 squirrels were harvested on the WMA and the estimated survival probability was 0.529 (85% CI: 0.398-0.645).  The estimated survival probability in the SP during the same period was 0.955 (85% CI: 0.929-0.971).  A second field season is being conducted in 2016; we hope to capture and radiocollar an additional 60 squirrels on each site.  We seek to improve our understanding of the survival rates of squirrels in hunted and non-hunted populations during the fall in Minnesota.  We anticipate that managers could use this information to alter season structures or access to hunters on public lands that are utilized heavily for squirrel hunting.