p < 0.001] and bears [b bear = 1.12, t(19) = 4.58, p < 0.001] over the 21-year period. Although annual mortality rates fluctuated for all three species, the spatial
distribution of strikes accounted for more of the variability in strikes for both elk
and bear, but not for deer (Table 9.2).
Relative Abundance
A total of 341 bear scats were detected on the CPR, resulting in a detection rate of
0.46 km
−1 year
−1 . On perpendicular transects, 599 elk pellet groups (5.98 km
−1
year
−1 ), 212 deer pellet groups (2.23 km
−1 year
−1 ), and 39 bear scats
(0.33 km
−1 year
−1 ) were detected. Relative abundance varied for elk
[v
2 (27) = 940.12, p < 0.001] and deer [v
2 (27) = 294.2, p < 0.001]. Bear scats were
unevenly distributed both on the rail bed [v
2 (27) = 263.3, p < 0.001] and on perpendicular transects [v
2
(27) = 125.4, p < 0.001] (Fig. 9.3c, d). The rail bed transects likely better represented relative risk for bears, because few bear scats were
detected along the perpendicular transects (n = 39) relative to the 341 scats detected
directly on the rail bed (Fig. 9.3d). Therefore, further analyses for bears were based
on rail bed scats.
Hotspots and Relative Risk
Six elk hotspots were identified (21% of the CPR segments), which were segments
with 29 or more strikes (Fig. 9.3a). Likewise, five deer hotspots (17% of the CPR
segments) were identified, which averaged 6.54 ± 1.73 per segment (Fig. 9.3b).
Bears were struck on average 2.86 ± 0.44 per segment, but no segment was
identified as a hotspot because no single segment incurred more than seven strikes.
After estimating the ratio of strikes to wildlife abundance for each segment,
overall non-constant risk was apparent for elk (v
2 = 286.1, df = 27; p < 0.0001),
deer (v
2 = 182.0, df = 27; p < 0.0001), and bears (v
2 = 7.4 Â 10
6 , df = 27;
p < 0.0001). High-risk segments were identified for each species (Figs. 9.1 and
9.3). Five, two and six high-risk segments were determined for elk, deer and bears,
respectively, and hotspots and high-risk segments differed in number and location
(Fig. 9.3).
146
B.P. Dorsey et al.
distribution of strikes accounted for more of the variability in strikes for both elk
and bear, but not for deer (Table 9.2).
Relative Abundance
A total of 341 bear scats were detected on the CPR, resulting in a detection rate of
0.46 km
−1 year
−1 . On perpendicular transects, 599 elk pellet groups (5.98 km
−1
year
−1 ), 212 deer pellet groups (2.23 km
−1 year
−1 ), and 39 bear scats
(0.33 km
−1 year
−1 ) were detected. Relative abundance varied for elk
[v
2 (27) = 940.12, p < 0.001] and deer [v
2 (27) = 294.2, p < 0.001]. Bear scats were
unevenly distributed both on the rail bed [v
2 (27) = 263.3, p < 0.001] and on perpendicular transects [v
2
(27) = 125.4, p < 0.001] (Fig. 9.3c, d). The rail bed transects likely better represented relative risk for bears, because few bear scats were
detected along the perpendicular transects (n = 39) relative to the 341 scats detected
directly on the rail bed (Fig. 9.3d). Therefore, further analyses for bears were based
on rail bed scats.
Hotspots and Relative Risk
Six elk hotspots were identified (21% of the CPR segments), which were segments
with 29 or more strikes (Fig. 9.3a). Likewise, five deer hotspots (17% of the CPR
segments) were identified, which averaged 6.54 ± 1.73 per segment (Fig. 9.3b).
Bears were struck on average 2.86 ± 0.44 per segment, but no segment was
identified as a hotspot because no single segment incurred more than seven strikes.
After estimating the ratio of strikes to wildlife abundance for each segment,
overall non-constant risk was apparent for elk (v
2 = 286.1, df = 27; p < 0.0001),
deer (v
2 = 182.0, df = 27; p < 0.0001), and bears (v
2 = 7.4 Â 10
6 , df = 27;
p < 0.0001). High-risk segments were identified for each species (Figs. 9.1 and
9.3). Five, two and six high-risk segments were determined for elk, deer and bears,
respectively, and hotspots and high-risk segments differed in number and location
(Fig. 9.3).
146
B.P. Dorsey et al.