Ah, rats — mild winter has a downside
Rodents squeaked through cold spells, now have city crews chasing their tails
August 22, 2012|By John Byrne, Tribune Reporter
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A city worker inserts pellets of poison into a rat hole in an alley on the South Side. Fifteen two-person teams have been responding to complaints from
residents. (Nancy Stone, Chicago Tribune)
Chicagoans rejoiced over the historically mild winter, but now many are experiencing the downside of
no deep freeze: the pitter-patter of tiny feet in neighborhood alleys, the sound of a city's rats thriving.
Complaints to City Hall about the omnivorous urban survivors — the bane of those who garden, walk
dogs or loathe leathery tails — are on the rise.
Through the end of July, the number of calls to the city's 311 center asking for a crew to get rid of rats
was up more than 28 percent compared with last year. The raw figures: 15,895 calls this year, compared
with 12,375 over the same period in 2011.
Department of Streets and Sanitation officials say they've put out more rat poison and are working
more efficiently this year. Teams are responding within six days instead of an average of nearly eight
days a year ago, according to city records. And the number of cases where crews put out poison to kill
rats was up more than 19 percent, to 18,339.
One explanation is that brown rats, the area's predominant species, likely rode out the chilly months
with uncharacteristic ease, according to Steve Sullivan, senior curator of urban ecology for the Peggy
Notebaert Nature Museum.
"Rats don't hibernate. They have to forage for food year-round, which is much more difficult if there's a
lot of snow and the temperatures plummet," Sullivan said. "So we usually see a significant die-off
between their first and second year. It's likely that didn't happen this past winter, though, because we
didn't have that long snap of frigid temperatures with deep snow."
Combine that with the furry rodents' tendency to breed like rabbits and eat "anything humans can eat,"
Sullivan said, and you have yourself a summer population boom.
The biggest percentage increase this year — a 176 percent jump — happened in the 2nd Ward, which
includes the South Loop. Yvette Morris has noticed the neighborhood is a little more crowded this
summer.
"Just this past week I asked myself, 'Where are these rats coming from?'" said Morris, who has lived in
the South Loop for 12 years.
Out walking her pugs Chloe and Rocco, Morris said she has witnessed some truly brazen rat behavior in
recent weeks.
"I'm out with the dogs three times a day, and I see them at all hours," Morris said. "Morning or night,
they'll just scamper across the sidewalk. Awhile back one came out onto the sidewalk and ran toward
us. I started screaming. It didn't seem very scared."
The rats aren't the only small mammals flourishing in the South Loop. Bunnies are through the roof as
well, Morris said, but their fluffy tails and reputation for carrying Easter eggs rather than the plague
earn them more "Awwwws" than "Ewwwws" from locals.
City crews have put out the most poison in the 35th Ward centered around the bustling Logan Square
neighborhood on the Northwest Side. The 941 cases through July 31 are a touch above the 926 in the
nearby 32nd Ward, home to affluent neighborhoods like Roscoe Village and Bucktown.
While rodent poison cases are actually down this year in the 32nd Ward by more than 11 percent,
they're up by 71 percent in the 35th Ward.
Paul Levin, executive director of the Logan Square Chamber of Commerce, said he hasn't heard
members complaining about an unusual number of rats around the hip bars and restaurants around
Milwaukee Avenue and Logan Boulevard. He dismissed the notion that the neighborhood's happening
night life creates more edible trash that supports more rodents, saying most of the buildings now
housing restaurants and clubs have long had businesses serving food.
But there does seem to be "a little more chatter than usual about rats" on online resident forums like
everyblock.com, Levin acknowledged.
Streets and Sanitation Commissioner Thomas Byrne has 15 crews of two people each on rodent duty.
The rat patrols drive from alley to alley in response to the 311 complaints, looking for the telltale hole
that indicates an underground burrow. Poison goes in the hole, and the workers post signs alerting
residents they've been in the area. Then on to the next complaint, the next hole.
Byrne acknowledged the warm weather might have grown Chicago's rat population. But with more than
18,000 cases already this year, the Streets and San teams haven't had much time to dwell on how
meteorological trends are affecting the numbers. "You get out there as quickly as you can after the call
comes in, deal with it as best you can — trying to identify the burrows — then on to the location of the
next call," he said.
Byrne is more fixated on the nuts-and-bolts drivers of rodent numbers: food, uncovered garbage, dog
feces, bird feeders and backyard gardens. Rats love to eat all that stuff, he said.
"If you don't get rid of the feces and keep your eye on everything else to make sure they aren't getting
into it, that makes it tougher," Byrne said.
This year could be a harbinger. Seth Magle, the director of the Urban Wildlife Institute at the Lincoln
Park Zoo, said if long-term warming continues, Chicagoans should get used to a city with more critters.
"If we don't have these (winter) die-offs, we should expect to see fluctuations in all kinds of species," he
said.
jebyrne@tribune.com
Twitter @_johnbyrne
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