Lincoln Park is using birth control to stave off rats
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Illustration: Brendan Lynch/Axios
A rat control experiment is halfway into its one-year pilot, and the alder pushing the project wants to see the concept citywide someday.
The big picture: Lincoln Park Ald. Timmy Knudsen launched the project last August with Lincoln Park Zoo and the Chicago Bird Alliance to distribute non-toxic pellets that function as birth control for rats.
- Scientists are monitoring eight blocks in the 43rd ward, chosen based on rat activity, commercial activity and 311 complaints.
Flashback: Previous population-control measures put toxic rodenticides in alleys and other popular rat hangouts. But other wildlife, including birds and dogs, suffered collateral damage.
Plus, poisoning rats is a short-term solution, as they are prolific reproducers.
Driving the news: Knudsen testified to the City Council's Committee on Environmental Protection and Energy this week about the Rat Contraceptive Pilot Project, telling his colleagues: "My hope is that by continuing to elevate this work publicly ... we work towards a day where abatement is done with more innovative, humane and sustainable materials."
How it works: Peanut butter attracts rats to the pellets, which contain a plant extract that interrupts sperm production and egg release in rodents, Lincoln Park Zoo's Maureen Murray tells Axios.
- The rats have to eat it every 30 to 60 days to prevent sperm production and egg release, but it's not hormonal like human birth control.
Between the lines: "It is a contraception and not a sterilant because we wouldn't want to put a product out there in the environment where, if they just ate it once, they would never reproduce again because of the risk of squirrels getting into it or other animals," Murray explains.
- The boxes containing the pellets are small enough to keep larger animals out.
What we're watching: The big test will be what the rat population looks like in the spring when they, like us, emerge in the warmer temps. Murray and her colleagues will compare the four blocks with the contraceptives to the four blocks where contraceptives were not placed.
