Foodie Rats Reject Poisoned Bait

New York has a thriving food scene and a lot of rats, and experts say the city's cuisine might make it harder to reduce the rodent population.

According to the Wall Street Journal, the Metropolitan Transit Authority wants to try a new pest-control system wherein tasty rat bait is left out, and when eaten it renders rats permanently infertile so they can't create more rats. The system has worked well in rural areas, but while country rats might be excited about the taste of rat bait, their city rat cousins have developed more sophisticated tastes and pooh-pooh the bait in favor of discarded pizza crusts and chicken McNuggets.

The National Institutes of Health has invested a $1 million grant to test ContraPest, the sterilizing bait, in an urban setting where its efficacy has been limited by "the abundance of more palatable food choices (i.e. trash)."

Scientists are planning a rat taste test and will scatter different flavors of rat bait around subway trash rooms to see if they can find a flavor and fragrance that will appeal to New York's snobbiest foodie rats. But finding a palatable flavor is complicated because the eating preferences of rats are determined in large part by what they're used to.

"Rats that grow up, say, from the dumpster behind a fast food chicken place, will love chicken," said rodentologist Dr. Robert Corrigan. "Bagel place, bagels. And so on."

Subway rats also like doughnuts, cookies, chocolate bars, peanuts, mayonnaise packets, apples, and cucumbers, Corrigan said. So the scientists will have to find a way to get "sterilizing bait" onto that list, or hide the birth control in other food.

"They'll either have to change the flavor or put it out with a hamburger or whatever the heck rats are eating," said Thomas Lamb, chief of innovation and technology for New York City Transit.