DC Tries Birth Control for Rats Despite Limited Data on Effectiveness in Citywide Use

Cities across the country are in a fierce battle to combat rats. In the nation's capital, the health department has tried plenty of ways to kill them.

Now, they're spending hundreds of thousands of dollars on a different kind of idea — rat birth control.

"We get the question all the time: 'Why would I use birth control on a rat? Why wouldn't I just kill them?'" said Brandy Pyzyna, vice president of operations for SenesTech, the company behind the birth control product.

Pyzyna says ContraPest is a long-term, more humane solution. She says in lab tests, the product pushed female rats into menopause and limited sperm production in male rats. They had no babies as a result.

But the News4 I-Team found the product has never been real-world tested on a citywide a scale — and some of the other cities that tried ContraPest in limited settings later opted to discontinue using it.

"I think this will be the real-world test," said Gerard Brown, head of rodent control for DC Health. "And then we'll have some information to back up the claim that it does work. And we hope it does."

It's a costly experiment. The District is spending $300,000 for ContraPest, the largest shipment of the product in the company's history. The mayor budgeted nearly a million dollars total for the product and additional staff members to deploy it.

"You've got to try anything, and if it does work, it's going to be the best money ever spent," said Scott Bennett, a restaurant owner in Adams Morgan.

Bennett's restaurant backs up to one of the alleys in which the product currently is being tested.

"Bring it on! You have my full, whole-hearted support," Bennett told the I-Team.

The News4 I-Team was there as crews began baiting 16 alleys across the District, two in each ward, with the product. They will monitor the amounts the rats consume and other signs of rat activity for six months and then assess whether complaints in the areas have dropped.

"So, definitely proving that a birth control works is quite challenging," Pyzyna said. "You should see fewer and fewer juveniles."

She says rats in the wild only live about six-to-eight months, but in that time they can breed thousands of pups.

The City of St. Louis told the I-Team ContraPest was so successful at the Gateway Arch Park, it's currently expanding its use of the product.

SenesTech's website touts successes at an animal facility and a multi-family housing complex in New York, claiming delivery of the product "to a substantial number of rats, which successfully reduced the infestation," and they "saw a reduction in rat activity in as little as one month."

The I-Team contacted the New York City Health Department, which also tested the product at a multi-family housing complex but said "no clear and consistent decrease in rat activity was detected over time."

Pyzyna says the successful study mentioned on the company's website was "in no way affiliated" with the NYC Health Department, adding that the health department never asked for help deploying the product, which could have affected its outcome.

The I-Team asked Brown whether the DC Health Department had contacted its counterparts in New York or any of the other cities that tried the product.

"We have not," replied Brown. "We believe without knowing that it's going to work."

A horse ranch in Arizona told the I-Team it's been really happy with the product, saying its rats are almost all gone.

A spokesperson for Chicago’s Department of Streets and Sanitation said it continues to test the effectiveness of ContraPest at different locations.

A Boston suburb said it stopped using the product because its rat population is not large enough to benefit and decided to use other treatments.

With rat complaints on the rise across the District, Brown says the innovative product is worth trying and will be used in conjunction with more traditional abatement tools like rat poisons.

"We are excited ... and we will be more excited if we determine that it's successful," Brown said, adding that he'll consider expanding the program if he believes the product is effective in reducing the rat population.

He said if it doesn't work, the city will have to keep trying other alternatives.

Reported by Jodie Fleischer, produced by Rick Yarborough, and shot and edited by Steve Jones.

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