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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.