Blue Ridge Country March/April 2021 - 43

" The proposed mitigations will improve public safety
and are a significant first step in improving landscape
connectivity of wildlife habitats in our region. "
- CASSIUS CASH, SUPERINTENDENT, GREAT SMOKY MOUNTAINS NATIONAL PARK

Wildlands Network. He defines habitat
connectivity as " the degree to which organisms are able to move freely across the
landscape. A wildlife corridor is the term
we use for a defined movement pathway
that-if protected or restored-would provide essential habitat connectivity for one
or more species, " he says. " Naturally one
of the best places to put wildlife crossings
is where you have a wildlife corridor that
gets cut off by a highway. "
How to help them cross
For years, road ecologists around the
world have been working to make roads
safer for both animals and humans. Europe, Canada, Mexico and many U.S.
states have already created effective wildlife crossings. Recent articles and videos
featuring crossing structures in Utah and
Texas have been shared widely on social
media.
Other regions have successfully solved
road ecology problems by improving existing structures like culverts that wildlife
use to cross, constructing mammal underpasses, and building large, expensive vegetated wildlife overpasses, which, when
paired with fencing, have been shown to
successfully reduce collisions.
In the steep vertical terrain of the Pigeon River Gorge, the best solution is not
as easy to come by as in the open landscapes of the west. Safe Passage has focused for two years on collecting data that
will prepare the group to collaborate with
partners in local departments of transportation on bridge improvements planned
for the next five years.
The first of these bridge repairs may begin as early as fall of 2021 at the Harmon
Den exit near the intersection with the
Appalachian Trail. Living on both sides of
I-40, a herd of elk now call this area home
after dispersing from a population reintro-

duced in the Smokies 20 years ago.
" The topography is driving where
these elk are moving, " says Dr. Liz Hilliard, a wildlife biologist with Wildlands
Network who is using GPS collars to research species movement and mortality in
the Pigeon River Gorge. " They're trying to
spend the least amount of energy, so they
follow low-slope areas, moving through
the landscape in what we call the path of
least resistance. "
It is important to locate wildlife crossings where animals wish to cross the road,
not just where it may be easy or convenient from a construction perspective. Scientists and researchers can help road planners know where animals try to cross by
studying wildlife mortality, collision data,
migration routes and the geographical terrain of the area.
While some animals take years to become comfortable using crossing structures, others can adapt to them rather

quickly. Fencing is often used to keep
wildlife off the highway and funnel
them to safe crossing opportunities, saving individual lives and helping populations thrive.
" The solution to addressing issues of
wildlife and highway interaction is twopronged: fencing plus crossing structures, " says Terry McGuire, a road ecology
expert and highway engineer now retired
from Parks Canada. " It has been shown
through research that one does not work
as effectively without the other. "
McGuire also points out that one type
of crossing does not necessarily meet every animal's needs and, ideally, a combination of various crossing types-like
a buffet of choices-should be provided,
spaced out in such a way that animals do
not need to travel great distances to find a
crossing opportunity.
While the concrete Jersey barriers prevent many individual crossings, scientists

HELP FOR THE SMALLER CREATURES
NATIONAL PARKS CONSERVTION ASSOCCIATION AND WILDLANDS NETWORK

Bobcats, coyotes, foxes, raccoons
and other medium-sized species
already use several existing culverts under Interstate 40, like the
one shown here. Large and small
creatures alike traverse the Pigeon
River Gorge landscape via a double
tunnel where engineers left habit
connected on top and inadvertently created a land bridge. Safe
Passage researchers are examining
" hotspots " where the most animals
are getting killed, as well as where
some are successfully crossing the
interstate-helping them learn more
about possibilities for mitigation
options. -FF

This bobcat, in a culvert under I-40, is
emblematic of the ability of smaller mammals
to find their way under roadways.

MARCH/APRIL 2021

Blue Ridge Country March/April 2021

Table of Contents for the Digital Edition of Blue Ridge Country March/April 2021