Wildlife Specialist report

almost three times less likely to hunt in an area for every 500-meter increase in distance
from a road. Watson (2005) reported that roads facilitate poaching of pronghorn.
Change in road miles from the existing condition is the indicator that analyzes the
potential for harvest effects under the different alternatives.
The literature also documents that ungulates typically respond to recreation activities by
avoiding areas near roads (Gaines et al. 2003). Elk avoid or move away from areas with
motorized use (Gaines et al. 2003, Johnson et al. 2000, Rowland et al. 2000, and Wisdom
et al. 2000). MacArthur et al. (1982) generally found that bighorn sheep avoid areas of
high vehicle use more than areas of lower vehicle use. Table 10 describes the road and
trail avoidance distances different researchers have documented for ungulates.
Table 10:
Species Activity Displacement
Reference
Elk ATV
Flight Probability of
62%
Distance
109 yds. (100 m) Wisdom et al. 2004
ATV
Flight Probability of
43%
545 yds. (500 m) Wisdom et al. 2004
ATV
Flight Probability of
25%
1,090 yds (1,000 m) Wisdom et al. 2004
Elk Road Driving 400 m Ward 1976
Elk Road Low Traffic < 0 to 1 vehicle per day 869 to 890 m Johnson et al. 2000
Road Medium Traffic 3 to 4 vehicle per day 909 to 1032 Johnson et al. 2000
Deer ATV
Flight Probability of
0.06%
109 yds. (100 m) Wisdom et al. 2004
ATV
Flight Probability of
0.05%
545 yds. (500 m) Wisdom et al. 2004
ATV
Flight Probability of
0.03%
1,090 yds (1,000 m) Wisdom et al. 2004
Deer Road Driving 800 m Perry and Overly 1977
Deer Road Avoidance 200m Rost and Bailey 1979
Deer ATV Experimental
250m Yarmoloy, Bayer, and Geist
Harassment
1988
Bighorn
Sheep
Roads and Trails < 500 visitors per year 100m Smith et al. 1991
Bighorn
Sheep
Roads and Trails > 500 visitors per year 150m Smith et al. 1991
Bighorn
Sheep
Road driving sheep fled at 132m Papouchis et al. 2001
Bighorn
Sheep
Road driving sheep alerted at 363m Papouchis et al. 2001
Bighorn
Sheep
Road driving no sheep response 821m Papouchis et al. 2001
Bighorn
Sheep
Vehicle traffic heart rate response < 200m MacArthur et al. 1979
Pronghorn Mean traffic affect zone on primitive roads for
ungulates
200m Gagnon et al. 2007
Pronghorn Mean hiking and Mountain Biking Alert Distance 329m Taylor and Knight 2003
Pronghorn Mean hiking and Mountain Biking Flight Distance 234m Taylor and Knight 2003
20