While the idea of
wildlife-specific crossings is nothing new to Banff National Park, it is only
in the last decade (and more predominantly in recent years) that scientists,
parks staff and researchers are beginning to comprehend and effectively utilize
the 30-odd years of research collected along Banff National Park’s section of
the Trans-Canada Highway.
Going back to the mid 1970s,
when the onslaught of ever increasing human traffic began, it was decided that
the amount of both human and wildlife fatalities due to highway collisions was
simply no longer acceptable. It was then that Parks Canada began to come up
with an ambitious plan; one that they most likely never imagined would make
Banff the world leader for animal specific crossings and attract researchers
from around the globe to come and observe their achievements.
By 1981, with highway traffic
increasing considerably on an annual basis it was time for major upgrades to
Completely bisecting the
park through the Bow Valley at a crucial area for wildlife feeding, mating and
dispersion of offspring, the Trans-Canada needed to be transformed from two
lanes into four while implementing a tangible plan that allowed wildlife the
same right of passage as the millions of visiting motorists. The goal was to
maintain ecological integrity amongst the parks diverse wildlife population.
In those plans it was decided
to build 22 underpasses and two overpasses over 45 kilometres of fenced-in
highway, as well as to create a progressive visitor education program that
would combat wildlife feeding and reduce the speed limit to 90 km/h.
effectively gave Banff more wildlife passages than any other place in the world
and positively modified visitor behavior to cut ungulate animal collisions by
over 96 per cent and non-hoofed animal collisions by over 80 per cent (given
that bears occasionally still climb over fences and animals such as coyotes and
wolves still find the need to sporadically dig under them).
Research using a mix of both primitive and modern day
techniques continue to this day, giving researchers a wealth of data on which
to study the movement and habits of all animals that now commute using these
Freshly racked sand pads
provide paw and hoof prints identifying different types of animals while silent
remote digital cameras snap four photographs in rapid succession at one second
intervals, recording behavior and how animals react while using crossings.
Strategically strung barbed wire retains fur or hair samples which can be used
to track individual animals and their anatomy through DNA testing.
With this information, parks
staff continually modify crossings to seem as comfortable and as natural as
possible for the diverse wildlife that depend on them for to roam freely
through the park.
The 50-metre-wide overpasses
that come with a price tag of $2.5 million dollars each contain several natural
features that attempt to blend into the natural landscape. Fifteen-metre banked
walls on either side block traffic out of sight and nearby native plants and
soils are planted along the crossings to camouflage into the landscape. Where
feasible, some underpasses mask the overhead noise of traffic with running
water as animals are more comfortable with crossings containing creeks.
With up to 24,000 cars a day
on that section of the Trans-Canada in summer months, the highway is currently
undergoing another major expansion from two to four lanes from Lake Louise’s
Castle Junction all the way to the B.C. border, which will involve building an
additional 16 underpasses and two new overpasses.
Speaking with Tony Clevenger
and Cathy Gill of communications for the Banff Wildlife Crossings Project of
Parks Canada, Pique Newsmagazine got a better insight on the project’s
successes, challenges and what lay ahead.
Pique: Since construction how
many animal crossings have taken place on or through the 24 over/underpasses
and what animals frequent them the most?
Parks Canada: In the past 11
years of monitoring, 11 species of large mammals have used the crossings more
than 95,000 times. Elk and deer use the crossing most. This is a result of
these two species being most abundant in the Bow Valley, not an indication of
greater preference by them or avoidance by other species. All large mammals in
Banff National Park use the crossings regularly.
Pique: Have there been any
new trends recorded with the crossings?
PC: Yes, there are a few
trends that we have observed. Firstly, research shows that there is a learning
curve for animals to begin using wildlife crossings after construction. It can
take up to five years for wary animals such as grizzly bears and wolves before
they feel secure in using the newly built crossings.
Secondly, results show that
some animals prefer certain types of crossings. For example, grizzly bears,
wolves, elk, deer and moose prefer wildlife crossings that are high, wide and
open, and have good visibility, whereas cougars and black bears show a
preference for smaller, more constricted crossings, ones that provide good
cover and protection. Basically species use crossing types that match what they
require for travel habitat.
Pique: What challenges do you
currently face and what challenges lay ahead?
PC: Learning more about how
populations of wildlife benefit from the crossings. Until now, our research has
addressed individuals, i.e., responses of different species to crossing types
and total number of times different species use the 24 crossings. For
transportation agencies to be convinced of the real benefits (and investment
cost-benefits) we need to be able to demonstrate scientifically their
importance to populations in terms of (1) survival of individuals within the
population and (2) how the crossings facilitate movement of all ages and sexes,
including breeding and reproduction. We are currently engaged in a three-year
research project using a noninvasive DNA-based technique to provide answers to
that question and using black and grizzly bears as the study species.
Perhaps the largest challenge
I see in the long-term is how transportation agencies are going to be able to
accommodate the growing transportation needs in the future. This is really
unsustainable ecologically and governments, politicians and transportation
agencies are going to need to take a serious look at less fossil fuel-dependent
means of transportation and moving towards increased public transportation
systems (e.g. rail).
Pique: Have other areas with
similar issues around Canada looked to Banff National Park for solutions or
PC: Yes. Banff is unique
worldwide. Banff is the only large-scale highway mitigation complex in the
world. Most highway mitigation projects for wildlife have at most four to five
wildlife crossings, whereas Banff has 24 large crossings on 45-km of the
Trans-Canada Highway. Eight additional crossings are being built today along
the segment of the TCH now being upgraded near Lake Louise. For this reason, we
have engineers and biologists from all over the world visiting Banff and
speaking with our wildlife research team and Highway Service Centre Director,
Pique: Will anything be done
differently for the next section of highway expansion?
PC: Yes. What has been
learned from six years of monitoring the first phases of highway construction
and data analyses is being used in the planning and construction of the next
sections. This is an ‘adaptive management’ approach to highway mitigation
planning, basically using research results from previous monitoring to guide
the planning and design of new crossings. The analyses of wildlife
preference/avoidance of crossing types are being used to guide the design of
new crossings. Simulation models based on animal movements of five large mammal
species in the Bow Valley were used to determine best placement of new
crossings. The structures will be slightly larger than crossings on previously
twinned sections of the Trans-Canada Highway in the park, primarily because the
upper part of the Bow Valley (a sub alpine ecozone) has a different suite of
wildlife, including higher densities of lynx, grizzly bears, moose and
There is little
information on crossing type preference for lynx and wolverine, because they
are rarely found in the lower Bow Valley where the existing crossing structures
Pique: There is some debate
on how to include the hamlet of Lake Louise into the plans. Can you elaborate
PC: The environmental
assessment for the current TCH twinning project adjacent to Lake Louise
recommended that the highway fence include the hamlet to reduce bear-human
encounters. Parks Canada explored this possibility, but at this time, it was
not feasible and the highway fence is being built along the right-of-way.
A fence behind the community
would have to cross the Bow River twice and the Canadian Pacific Railway (CPR)
three times. At these points, fence structures must prevent wildlife passage
but allow usual river recreation and railway traffic. Parks Canada tested river
and rail structures within a short fence section to assess how well they would
deter large animals. The deterrents tested at the CPR openings did not meet
wildlife exclusion targets set by Parks Canada in time to meet the TCH Twinning
construction schedule. With the cooperation of the CPR, Parks Canada will
continue to test deterrents at fence railway openings. A fence behind the
community to exclude grizzly bears from the hamlet remains a possible option.
This would benefit both people and grizzly bears.
Pique: What is the scheduled
completion date for the second phase of the highway expansion?
PC: Within the remaining
35-km section of two-lane highway in the park, a nine kilometre segment is now
being upgraded to four lanes with completion expected in fall 2008.
Further twinning will occur as funding
Pique: Any additional
information people should know?
PC: Ungulate vehicle
collisions have dropped from an annual average of over 100 per year to less
than half dozen today between Castle Junction and the park’s east gate.
Approximately 65 per cent of all accidents (outside the park) involve wildlife
while in Banff National Park it is 13 per cent (slightly more than one in 10).
Highway mitigation for
wildlife may appear to be costly to motoring public and taxpayers, but with
average elk-vehicle collision costs being over $10,000, recent studies have
shown these measures pay for themselves in several years.
Back on the Sea to Sky
corridor where several wildlife crossings incorporated into the current highway
upgrades will help reduce wildlife collisions. Four underpasses are to be put
in south of Whistler in the Pinecrest area and one is already in place near the
Horseshoe Bay area. The highway will also include several small-scale culverts
to accommodate smaller critters crossing needs as well.
TONY CLEVENGER has been an
independent researcher contracted by Parks Canada since 1996 to carry out
long-term research assessing the performance of mitigation measures designed to
reduce habitat fragmentation on the Trans-Canada Highway in Banff National
Park, Alberta, Canada. In September 2002, he began working for the Western
Transportation Institute (WTI) at Montana State University, while continuing
his research in Banff and the Mountain Parks. In 2005, Tony garnered support
from Parks Canada, Montana State University, and three large North American
conservation foundations to partner in funding his long-term research until
Tony is currently a member of
the U.S. National Academy of Sciences Committee on Effects of Highways on
Natural Communities and Ecosystems. Since 1986, he has published over 40
articles in peer-reviewed scientific journals and has co-authored three books
including, Road Ecology: Science and Solutions (Island Press, 2003). During the
last 9 years in Banff his research has resulted in 17 peer-reviewed
CATHY GILL is the Outreach
and Education Coordinator for the Trans-Canada Highway Project.
She develops and delivers the
school-based and public outreach programs for the project.
For more information on the
TCH project, please visit: