MAKE ROADS SAFER FOR HUMANS AND WILDLIFE
by Whit Gibbons
February 22, 2004
was a positive one for me ecologically. First, Matt Aresco (graduate student,
Florida State University), Kimberly Andrews (graduate student, University
of Georgia), and I captured a mud snake in Lake Miccosukee in Florida.
Second, I got to see firsthand the amazing advances in conservation Matt
has made at Lake Jackson, near Tallahassee.
most people would not like to wade around in a Florida lake on a cold,
rainy day in February and catch any kind of snake. But to us, the mud
snake capture was exhilarating. For one thing, the presence of a mud snake
is usually indicative of a healthy environment. Plus, they are absolutely
beautiful--shiny black above, checkerboard red and black on the belly.
They are considered rare in most southern regions where they occur, and
many herpetologists have never seen one in the wild.
have a remarkably selective diet as adults, eating primarily giant salamanders.
When these enormous amphibians are in a lake, crayfish and other invertebrate
animals normally abound also, and the aquatic vegetation is usually luxuriant.
For the smaller invertebrate creatures to be present, the waters must
generally be unpolluted. Mud snakes, sitting atop an intricate food pyramid,
are dependent on the lower portions remaining intact, hence they serve
as excellent indicators of overall environmental conditions.
Jackson, a 4000-acre sinkhole lake near Matt's home, offers a different
kind of threat to mud snakes than the disappearance of their favorite
prey. Relatively clean waters, plenty of vegetation and invertebrates,
as well as giant salamanders and mud snakes, are present at the lake.
But the road that bisects Lake Jackson was built in the 1920s, when transportation
departments considered only the engineering aspects of highway construction,
with little attention to environmental consequences. As time progressed,
U.S. Highway 27 became a major thoroughfare in Florida, with more than
20,000 vehicles per day.
as lake-dwelling animals search for food, mates, and nesting or hibernation
sites, many travel overland to other lakes. Unfortunately, mud snakes
and other aquatic species including turtles, watersnakes, bullfrogs, and
even giant salamanders try to make the trip each year across the four-lane
highway separating the two parts of Lake Jackson. Few make it alive. Although
the list of road mortality victims is long, among the most obvious are
the turtles, with an incredibly high road-kill rate of 98%--more than
2,000 per mile per year. Lake Jackson became known as "home to the
world's worst turtle-killing highway."
first became concerned about Lake Jackson's wildlife in February 2000
when on a single day he found 90 road-killed turtles along a short portion
of the highway. Over a 3-year period he documented attempted crossings
and highway deaths of more than 10,000 individual animals representing
more than 40 species. After many phone calls and personal visits, he got
permission from the state highway department to set up a barrier silt
fence between the highway and the two lakes. He constructed two miles
of temporary fencing himself, placing it parallel to the road, leading
animals to a single culvert connecting the two bodies of water beneath
the highway. Such under-the-road crossings for wildlife are known as ecopassages,
a positive ecological step that can reduce or eliminate road mortality
for some species.
step was to make the local community aware of the constant carnage on
the highway in hopes that his temporary solution could be replaced with
a permanent wall and multiple ecopassages. The task was not easy, as he
faced the obstacles of political and commercial interests that anyone
does when trying to set things right environmentally. But he persisted,
and ultimately inspired action among others in the community and the state.
The Lake Jackson Ecopassage Alliance (http://www.lakejacksonturtles.org/)
now comprises a group of environmentally concerned citizens intent on
developing permanent guide fences and ecopassages to allow animals to
move freely, and safely, between the two parts of Lake Jackson.
serves as a dramatic example of the effectiveness of using barriers to
redirect the travel pattern of animals to avoid highway mortality. More
importantly it shows that we still have heroes around like Matt Aresco,
who will work single-handedly against steep bureaucratic odds to protect
the environment. I imagine the mud snakes appreciate his efforts, too.
you have an environmental question or comment, email