=Wolves, Bears and Mountain Lions -- To Move Into Cities
ScienceDaily (Oct. 5, 2012) —
About five miles from Chicago O'Hare International Airport, scientists
have located the smallest known coyote territory ever observed. For at
least six years, a coyote community has maintained its existence within
about a third of a square mile.
"That's an indication that they don't have to go far to find food and
water. They're finding everything they need right there, in the suburbs
of Chicago," said Stan Gehrt, an associate professor of environment and
natural resources at Ohio State University who has led the tracking of
coyotes around Chicago for 12 years. "It amazes me."
Coyotes are the largest of the mammalian carnivores to have made their way to, and thrived in, urban settings, Gehrt said.
"The coyote is the test case for other animals. Raccoons, skunks,
foxes -- they've already been able to penetrate the urban landscape
pretty well. The coyote is the most recent and largest. The jury's out
with what's going to happen with the bigger ones," he said.
The bigger ones include wolves, mountain lions and bears. Mountain
lions have been seen on the fringes of cities already, and one was shot
near the Wrigleyville neighborhood of Chicago.
"They are going to be an even bigger challenge," Gehrt said.
Since the tracking of urban coyotes began in 2000, Gehrt and his team
have captured and placed radio collars on about 680 coyotes, with 50 or
60 being tracked at any one time. He estimates that about 2,000 coyotes
live in the Chicago metro area, along with 9 million people in some 250
separate municipalities.
At times, this co-existence can cause uneasiness among humans. But by
Gehrt's estimation, all species of urban dwellers are probably going to
have to get used to it.
"It used to be rural areas where we would have this challenge of
coexistence versus conflict with carnivores. In the future, and I would
say currently, it's cities where we're going to have this intersection
between people and carnivores," he said. "We used to think only little
carnivores could live in cities, and even then we thought they couldn't
really achieve large numbers. But we're finding that these animals are
much more flexible than we gave them credit for and they're adjusting to
our cities.
"That's going to put the burden back on us: Are we going to be able
to adjust to them living with us or are we not going to be able to
coexist?"
Gehrt described the research in a talk October 5 at EcoSummit 2012, an international conference held in Columbus.
The tricky part of any government-sponsored eradication program is
the question of cost versus benefit. When the study began in 2000,
several communities around Chicago trapped and killed coyotes found
within their boundaries. Gehrt estimates that only 10 percent of
communities have such programs in place now.
"I think those programs will go away, too. It costs money, and it
upsets some residents who want coyotes living there. So there is
conflict, cost and lack of effectiveness. We have great data in areas
where removal was done. You pull them out, and literally within just a
few weeks, new coyotes moved in and set up a new pack and began
reproducing right away," he said.
Gehrt noted that the encroachment goes both ways. Humans have not
been a predominantly urban species for all that long worldwide, though
about 80 percent of U.S. residents live in cities. One reason humans
flocked to cities was to get away from the risks associated with living
near wild carnivores.
"The funny thing is that now we have more people on earth and bigger
cities than ever, we also now have carnivores moving into cities. It's a
two-way street: We're expanding cities into their territories and
they're also coming in," said Gehrt, who also holds appointments with
the Ohio Agricultural Research and Development Center and Ohio State
University Extension.
In comparing his findings about coyote survival in cities to research
by another group on those living in rural areas, Gehrt has found that
the urban coyote pup survival rate is five times higher than the rate
for rural pups. In both environments, humans are the coyotes' primary
predator.
"We are the only thing slowing their population down, either with our
cars, which is the No. 1 cause of death for coyotes, or when we remove
them through hunting or control programs," Gehrt said. "None of the
diseases they're exposed to really impact them at all."
Coyotes are exposed to disease because they dine on rodents, rabbits
and geese, providing a benefit by reducing human exposure to diseases
carried by those species and removing animals otherwise considered a
nuisance. They will also eat bugs and deer fawn, another potential
benefit because human encounters with deer can be deadly, and will gorge
on fruit if given the opportunity. They also eat the occasional cat or
small dog.
Opportunity for food appears to abound in urban areas, which is why
coyote communities can thrive in such small, contained spaces. Once they
settle, resident coyotes don't move much. Transient animals, typically
youngsters that have recently left their parents' pack, will try to find
a vacancy in an existing territory or find a new area to start their
own pack.
"They're so adaptable and so opportunistic," Gehrt said. "In
adjusting to urban life, they may change dietary items and habitat use,
and become nocturnal, whereas in the country they're active day and
night. But with other things, they don't change at all. Here, they're
able to maintain their social structure, territorialism, packs and
mating system, even in the face of all these challenges of trying to
live among 9 million people."
Gehrt recently published a paper describing how coyotes in Chicago
have remained monogamous in the midst of adjusting to their new, urban
way of life.
He is expanding his research to a few other sites, including
Cleveland, Ohio, and in Nova Scotia, where coyotes show more
aggressiveness toward humans.
However, under typical circumstances, Gehrt said coyotes are not
prone to attack humans. For those people who see a coyote and do feel
threatened, waving one's arms and yelling, or even throwing a rock in
its direction, will very likely scare the animal away.
"You're doing them a favor. They show a healthy respect and fear of people and that's the way it should be.
Gehrt's study is funded by Cook County (Ill.) Animal & Rabies Control.
Story Source:
The above story is reprinted from materials provided by Ohio State University. The original article was written by Emily Caldwell.
Note: Materials may be edited for content and length. For further information, please contact the source cited above.
Ohio State University (2012, October 5).
Urban coyotes could be setting the stage for larger carnivores --
wolves, bears and mountain lions -- to move into cities.
ScienceDaily. Retrieved October 7, 2012, from http://www.sciencedaily.com /releases/2012/10/121005100909.htm
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