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CHICAGO - A new tactic is being used in Chicago's ongoing battle against the unwanted rat population.
The Department of Street and Sanitation has added seven new crews to its "Bureau of Rodent Control" -- bringing the total number of crews to 25.
However, it is ultimately on residents and dog owners to win the war against rats.
They are clever, persistent and they do some things way better than humans do.
"You and I might smell a cake that's been baking? They would smell each of the ingredients," Orkin said.
"They can literally gnaw through the wall of a building to escape the cold," said rat expert Adam Andrzejewski.
Factors like this make Chicago's "Norway Rat" population a very difficult foe.
Streets and Sanitation crews -- which drop poison around the city for the rats -- can only do so much. Experts say it is on business owners and residents to step up their property hygiene.
"Up on the North and Northwest Side, you have restaurants, you have grocery stores, you've got a lot of people who rent homes who aren't disposing of their trash properly," Andrzejewski said.
Dog owners, this means you.
"Rats love that nutrient-rich, dense fecal matter. Dispose of your pet waste in a covered container," Andrzejewski said.
"The things that they're looking for are food, water, and safety, security, coverage, mates," Orkin said. "If you can reduce the availability of those things, the rats will go elsewhere."
He also says to close any trash and recycling bins you notice left open, and have the city replace any bins with holes chewed by rats.
"Ultimately, the more we can educate people, the more we can reduce it around the whole city," Orkin said.