Habitat Selection by Parturient and Post-parturient Adult Female Moose (Alces alces) on the Canadian Prairies

Abstract

The expansion of moose into the agricultural landscape of Saskatchewan (i.e., farmland moose) has increased human-wildlife conflicts, raising questions about how to best manage them. To support decision making, I initiated a study on farmland moose reproductive success and habitat selection following parturition (i.e., birth of calves). In 2013 and 2014, adult female moose were captured between Saskatoon and Chamberlain, SK and fitted with Global Positioning System collars. Daily movement rates and clustering of locations were used to determine the date and location of parturition for 27 adult female moose from 2013 to 2015. The mean date of parturition was May 21. Moose were surveyed using Very High Frequency radio telemetry in June and September each year to visually determine the presence and number of calves. Of the pregnant females observed during calf surveys with 1 or 2 calves, twinning rates were 67% (n = 6/9) in June 2013 and 46% (n = 5/11) in June 2014. Habitat selection ratios indicated that wetland and riparian habitat, trees and shrubs, and cropland were selected the most strongly by female moose as parturition habitat, while pastures and forages, developed and native grassland habitat were avoided. Female moose selected parturition sites further away from roads. A resource selection function model was developed to quantify habitat selection by 15 female moose with young during the first 20 days post-parturition. During this period, adult female moose with young most strongly selected for wetland and riparian areas (β [95% CI] = 0.716 [0.485, 0.946]) and native grassland (β [95% CI] = 0.457 [0.329, 0.585]) and against oilseeds (β [95% CI] = –0.252 [–0.400, –0.103]). Predictive success of the top-ranked model, estimated from k-fold cross validation, was rs = 0.993 (SE = 0.001). The resource selection function indicates that only 10% of the area within the home ranges of parturient females is considered highly selected habitat with high probability of moose use, while 48% of the area has a low probability of use. These results demonstrate the importance of wetland habitat within cropland to female moose, during and shortly after giving birth.