Pierre River Mine Project

TERRESTRIAL AENV SIRS 44 – 78
Question No. 71
Request Volume 2, SIR 459a, Page 23-139.
Section 13.1
In response to the SIR asking how long sight lines will mitigate impacts on
wildlife, Shell suggests that this measure will reduce vehicle-wildlife collisions.
Shell goes on to state that The construction of long lines of sight along roads is
intended to mitigate impacts on medium to large size species, however Shell
acknowledges that building straight roads with long straight sight-lines will not
affect all species in the same way.
71a What other consequences, (for example, reluctance to cross or improved
detection by predators) could long sight lines potentially have on wildlife?
Response 71a Long sight lines may increase the reluctance of some species to cross roads (e.g.,
Dyer 1999, Dyer et al. 2002), or they may increase prey detection rates for
predators (e.g., James 1999). However, they may also increase driver visibility
thereby reducing accident rates. Increased driver visibility as a result of
vegetation clearing on roadsides has been documented to reduce wildlife vehicle
collisions (e.g., moose; Seiler 2005).
References
One documented example of risk to wildlife populations from vehicle collisions
is from a woodland caribou herd in Alberta, where an 11% mortality rate from
collisions with vehicles on a major highway, combined with a natural mortality
rate of at least 10% (Edmonds and Smith 1991) exceeded the average calf
recruitment of 14%. The effect was reported to have likely resulted in a
population decline (Brown and Hobson 1998). Although the potential for
increased predator detection rates for prey exists using long sight lines for roads,
Shell is unaware of a documented wildlife population decline due to long sight
lines alone. In addition, research using individual-based movement models for
wolves, caribou and moose to determine how linear developments affect wolf
movements and consequently predator-prey interactions suggest that the number
of predators on the landscape is more important than the number of linear
developments when explaining caribou and moose survival (McCutchen 2006).
As it is unlikely that the project will increase the number of predators within the
RSA, it is predicted that any change in the predator-prey encounter rate would
not impact the viability of regional wildlife populations.
Brown, W. K. and D. P. Hobson. 1998. Caribou in West-central Alberta:
Information Review and Synthesis. Prep. for: The Research
Subcommittee of the West-central Alberta Caribou Standing Committee.
74 pp + Appendices.
Dyer, S.J. 1999. Movement and Distribution of Woodland Caribou (Rangifer
tarandus caribou) in Response to Industrial Development in Northeastern
Alberta. M.Sc. Thesis. University of Alberta. 106 pp.
April 2010 Shell Canada Limited 13-65
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