3.4 | Coyote use on raccoon temporal activity (Figure 1b,c)
Overall, our hypothesis for raccoon-coyote temporal interactions was largely correct, with raccoons at DMP consistently exhibiting no shift in time use relative to coyote intensity of use zones. However, there was reduced overlap between coyotes and raccoons within the high coyote zone. Results for the other sites varied by survey year (Figure 3). Below, we first present for each site the results for the comparison of raccoon activity between the high and low coyote zone. Then we provide the comparison of raccoon and coyote temporal activity within the high coyote zone (relative to the same comparison in the low coyote zone), to determine if there is evidence that a shift in raccoon activity between zones is due to temporal avoidance of coyotes.
HMC: At the most rural site, we found results for the effects of coyotes varied by survey. The 2016 and 2017 surveys exhibited no shifts, while surveys in 2018 and 2019 showed significant shifts in raccoon activity between coyote low and high zones (W = 15.12, 10.02,p < 0.00 respectively) (Table 1). Results were consistent even when the 2017 survey was broken up into summer and winter survey seasons since it covered an entire year, indicating no shifts in raccoon activity between coyote zones. When comparing coyote and raccoon temporal activity within each zone the 2018 survey showed some evidence of decreased temporal overlap between coyote and raccoons in the high coyote zone, while for 2019 the confidence intervals were too wide to be meaningful (Figure 3).UMBS: For both surveys, we found there were significant shifts in raccoon activity between coyote zones (W = 9.63, p < 0.00 for 2016, and W = 7.39, p = 0.025 for 2015). Both surveys showed evidence of reduced temporal overlap between coyote and raccoons in the high coyote zone.
SNWR: We found that again, results varied by survey, with two out of three surveys showing significant shifts in raccoon activity between coyote zones; 2016 (W = 6.08, p = 0.047) and 2018 (W = 10.46, p < 0.00) showed shifts, while in 2017 (W = 3.65, p = 0.162) raccoons did not shift activity. Only the 2018 survey showed evidence of reduced temporal overlap between coyotes and raccoons in the high coyote zone.
DMP: We found that raccoons exhibited no shifts in activity between coyote zones consistently across for all four years surveyed in our study. Curiously, three out of the four surveys (2018, 2019, and 2020) showed evidence of reduced overlap between raccoons and coyotes in the high coyote zone, with the difference reaching significance in the 2020 survey (Δ4 CI in the high coyote zone: 0.46-0.58 vs. low coyote zone: 0.61-0.80).