Chicago is overrun with rats, and residents hope that feral cats will save the day. As The Wall Street Journal reports, an explosion in the Windy City’s rodent population has caused desperate homeowners and businesses to adopt stray felines from shelters en masse. They hope that if they treat the kitties well, they’ll stick around and hunt neighborhood vermin. But thanks to skyrocketing demand, it’s no longer so easy to adopt an alley cat.

Chicago’s weather is notoriously cold, but last year’s mild winter meant that more baby rats survived to see adulthood. They multiplied, and by September 2016, the city’s rat complaints had increased 40 percent from 2015, according to The WSJ.

In response, animal rescue outlets have received so many requests for cats that one rescue program, the Tree House Humane Society’s Cats at Work program, has a six-month waitlist for adoption. (The Cats at Work Program traps, spays or neuters, and microchips feral felines, and gives them to Chicagoans with rat problems.) Paul Nickerson, the program’s manager, was even offered bribes by a local restaurateur wanting to hurry up the process.

“If people found out I was bumping people to the front of the list they would kill me," Nickerson told DNAinfo Chicago. "I just can't do it, it's just not fair to everybody."

To encourage their wild guests to make themselves at home, people are treating their adopted feral cats like kings. Local brewery Empirical Brewery built its adopted strays a custom, multi-tier cat condo, and other adoptive cat owners have constructed feeding stations, installed heated cat houses, and spoiled their finicky kitties with tasty food.

But feral cats alone won’t solve Chicago’s rat problem. To curb the rodent population, locals are also employing other methods, including injecting dry ice into rat nests to asphyxiate them, offering public education campaigns, and even launching an official Bureau of Rodent Control under the city’s sanitation department.

[h/t The Wall Street Journal]

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