- Date: Sat, 27 Feb 1999 14:24:47 -0800
(PST)
- From: eotl@west.net
- Mime-Version: 1.0
- To: neff1@mindspring.com
- Subject: ABCNEWS.com : How Animals Cross
the Road
- Cc: eotl@west.net
-
-
- How Animals Cross the Road - Wildlife
Undercrossings
-
- By Warren Richey
- The Christian Science Monitor
- 2-27-99
-
- At Mile Marker 78, Alligator Alley,
FL - About a quarter of the way from
- Naples to Fort Lauderdale on this remote
cross-Everglades highway in
- Florida, the interstate passes over a
grassy culvert.
-
- To most motorists zooming past at
70-plus miles an hour, the bridge is
- nothing more than a thud-thud under their
radials.
-
- But if they actually pulled over
to the side the road and clambered
- down the steep embankment, they would
find themselves face to face with an
- environmental innovation that is changing
the way highways are being
- designed around the world.
-
- Here in Florida, they call it a
panther crossing. In Canada, the same
- idea works for elk and deer. In England,
a much smaller version helps keep
- migrating toads in hopping form.
-
- The basic strategy is to create
a safe, natural means for wildlife to
- cross a road without endangering their
own lives and those of unsuspecting
- motorists.
-
- Avoiding Wildlife Isolation
-
- Highway planners and ecologists in Florida
came up with the idea of a
- wildlife underpass more than a decade
ago when major improvements to
- Alligator Alley threatened to isolate
a large section of the Big Cypress
- National Preserve.
-
- They needed to find a way to keep
animals off the road. But they also
- needed to allow animals - like the endangered
Florida panther - to
- continue to hunt and roam in their native
habitat on both sides of the
- highway. The solution: fence the entire
length of the highway and funnel
- the wildlife into culverts passing safely
under the traffic.
-
- It wasn't cheap. Thirty-six culverts
were constructed along a 40-mile
- section of Alligator Alley at a cost
of $13 million.
-
- Example for Others
-
- But today, the project is hailed as a
shining success and has been studied
- by engineers and ecologists facing similar
problems in Canada, Mexico,
- Australia, and countries throughout Europe.
Some ecologists - including
- pioneering environmentalists in the Netherlands
- have taken the concept
- one step further with the development
of wildlife overpasses.
-
- It is all aimed at helping to reduce
the negative impact of highways
- on natural ecosystems.
-
- The crossing at mile marker 78 on
Alligator Alley is carpeted with
- grass and ferns and affords skittish
animals a wide view all the way
- across to the other side. To the north,
it leads into the cover of a dark
- cypress forest. To the south, it passes
through a line of willows into a
- sawgrass wetland surrounded by slash
pine and cypress trees. The only
- apparent drawback is that every three
to five seconds a car or 18-wheel
- tractor-trailer roars overhead. It fills
the crossing with a jolting
- whoosh and rumble.
-
- Nonetheless, the crossings work.
Fresh deer and raccoon tracks mark a
- muddy game trail that snakes through
the culvert. A 10-foot fence topped
- by three strands of barbed wire prevented
me from checking the entire
- crossing for panther tracks. But ecologists
working with radio tracking
- collars and heat-sensing cameras have
verified that panthers and other
- animals are using the culverts.
-
- Gators and Panthers and Bears, Oh My!
-
- "All the animals that are down there
are using the crossings," says Gary
- Evink, an ecologist with the Florida
Department of Transportation. "We
- have everything from alligators, to wading
birds, to bears and panthers."
-
-
- Mr. Evink and his colleagues at
the Florida Department of
- Transportation are leaders in a campaign
to encourage sensitivity among
- highway engineers to the ecological effects
of their work. Florida is
- sponsoring an international conference
on transportation and wildlife set
- for this September in Missoula, Mont.
-
- The idea of helping wildlife cope
with disruptions caused by highways
- is still a new concept. Experts are finding
that highways create
- significant barriers to the natural interconnection
among animals within a
- large region.
-
- Busy highways can split wildlife
into small, fragmented populations
- that are much more vulnerable to population
fluctuations because they,ve
- lost their ability to roam and interact.
-
- Slowly Criss-Crossing Everything
-
- "One percent of the United States
is covered by roads and roadsides. That
- is an area about the size of South Carolina,"
says Richard Forman of
- Harvard University in Cambridge, Mass.,
an expert on the impact of roads
- on wildlife. "Society hasn't come
to grips with the ecological effects of
- this road system, but it is beginning
to."
-
- Some experts suggest examining the
problem from an animal's
- viewpoint. On a typical four-lane highway
carrying 20,000 vehicles a day,
- a car or truck would pass every 4 seconds.
"Not many animals are going to
- get across that road - not alive anyway,"
says Paul Garrett, an ecologist
- with the Federal Highway Administration.
"Roads effectively can become
- very solid barriers to a lot of species
of wildlife."
-
- At Banff National Park in Alberta,
Canada, ecologists are working to
- mitigate the impact of widening the Trans-Canada
Highway to four lanes.
- They used a combination of fencing, wildlife
underpasses, and overpasses,
- and recorded a 96 percent reduction in
road kill of elk and deer.
-
- A Lot to Get Used to
-
- Grizzly bears, wolves, and cougars regularly
use the underpasses. Bruce
- Leeson, of Parks Canada, says he is confident
that the park's two new $2
- million overpasses will be just as popular.
He says wolves and grizzly
- bears are very wary animals. "It
takes them time to find these new
- structures," he says. "Then
it takes them time to get up the courage to go
- through them."
-
- In Florida, transportation officials
are planning construction of
- their first wildlife overpass. It will
be built south of Ocala and will
- extend over I-75 at a cost of about $2.6
million. One goal is to encourage
- bears to roam from the Ocala National
Forest to Florida's western coast,
- where bear populations are isolated and
in decline.
-
- In another innovative project, Florida
officials are beginning work
- on a means to keep frogs, toads, snakes,
and alligators off State Road 441
- south of Gainesville where the road bisects
the Paynes Prairie State
- Wildlife Preserve.
-
- The plan calls for construction
of a three-foot-high wall with an
- 18-inch lip protruding outward to block
the slippery critters from
- crawling or hopping out onto the road.
Instead, they will be directed to
- four culverts under the highway.
|
