Urban rats are thriving in a warming world, and the implications are troubling. As temperatures rise, rate are finding more opportunities to eat and reproduce, leading to a surge in sightings across major cities like New York and Washington, D.C. Benji Jones explores the links between climate change and rat populations, and why our traditional methods of control are failing and what cities can do about it.
Taken together, this means that as cities warm, rats have more time to eat and mate, and they can more easily locate food. This could help explain why New Orleans didn’t see an increase in rats, Parsons says. The city already has a warm, subtropical climate, so additional warming may provide less of a benefit for its rats. Too much heat could eventually become a problem, Richardson says, but rodents seem to be less limited by heat than by cold.
“Rats would still be in northern Mongolia hanging out in their burrows if it weren’t for these food crumbs that were dropped all the way across the continents,” he says. “It’s just so much easier for us to kill another species and bludgeon it to death—in some cases, torture it—than it is for us to just pick up after ourselves.”