Outrunning the rats

Birds do it. Bees do it. Even rats do it.

Not fall in love—procreate.

And that’s the hinge of a Chicago experiment aimed at reducing the rat population without using poison.

Rats are everywhere. New York City estimates it has about 3 million of them. Municipalities have traditionally relied on rodenticides to control their numbers, but these poisons can also kill other animals.

Now, a Chicago project led by Lincoln Park Alder Timmy Knudsen, the Lincoln Park Zoo and the Chicago Bird Alliance is testing another method: rat birth control.

The partners are mixing contraceptive pellets into peanut butter. The treatment works for several months, interrupting sperm production and egg release in rodents, according to reports.

They’ll count the rat population this spring to see whether the experiment is working.

And there’s good news for Louisiana, where our most hated pest—the mosquito—is getting similar treatment. Some cities have begun releasing genetically altered mosquitoes to disrupt the reproductive cycle. Their offspring are born unable to reproduce, stopping the next generation before it starts.