PETA has a suggestion for Mayor Cherelle L. Parker: Put the city’s rats on birth control.
The animal rights organization sent Parker a letter on Oct. 14 urging Philadelphia to consider contraception instead of poison to control its rodents. It also promised to send Parker a “Rats Have Rights” mug.
The appeal arrived six days after City Council adopted a resolution calling on various city departments to develop a coordinated response to persistent rat infestations in Philadelphia’s Lower Northeast section. Residents in Oxford Circle, Castor Gardens, and surrounding neighborhoods have reported infestations around their homes and businesses. In some cases, they claim, rats have chewed through car wiring, leaving residents with costly repair bills.
PETA argues that killing rats brings only temporary relief because rodents from nearby areas quickly move into the newly open territory. And, they say, poison can also harm pets and other wildlife. As a solution, the organization wants Philadelphia to pair better trash storage with contraception instead.
So, does rat contraception work?
Several studies have shown that using birth control to control rodent populations is a valid approach, at least in theory. That’s because it addresses the most fundamental challenge of rodent population control: Rats reproduce faster than city authorities can kill them.
“Rodents are the fastest breeding animals on earth,” said Loretta Mayer, a biologist and former CEO of Senestech, a biotech company specializing in rodent control. “We’ve been killing these animals for centuries, and we have more than we ever have before. The strategy of killing doesn’t work.”
However, whether rat contraception is a theoretical valid concept or an actually effective strategy remains unclear.
Several cities, including Baltimore, Chicago, and Washington, D.C., have recently tested various rat contraception products, and initial results seem promising. For instance, in D.C., researchers found that rat activity declined substantially in two neighborhoods after introducing the rat contraceptive ContraPest.
Meanwhile, a pilot program in Boston reported a 60% drop in rat activity after using a different form of birth control called GoodBites.
Now, New York City is testing ContraPest, GoodBites, and Evolve, another contraceptive bait, alongside a noncontraceptive control, to see just how effective birth control really is. The city will use the results to decide whether to include birth control in its broader, multipronged approach to rodent control.
Philadelphia’s health department is not ready to take that step.
“We do not use unproven techniques,” said Jason Brooks, news media coordinator for the Department of Public Health, “like other agents that may affect their reproductive systems.”
Mayer agreed that more research is needed but disputed the department’s characterization of the method’s efficacy being unprove. “It is early in the technology,” she said. “We need more data.”
If Philadelphia ever did decide to test contraception, Mayer said, it would need a carefully designed study and a reliable way to measure the results.
“The most accurate method is using cameras and counting the number of animals that go [to the feeding station] over a long period of time,” she said. “You have to measure the consumption of the pellet, too.”
Together, those measurements would show whether rat activity actually declined and whether birth control was, in fact, responsible for the decrease. Still, for Mayer, success would mean bringing the rodent population under control, not making Philadelphia rat-free.
“You’re never going to kill them all,” she said.