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And on Monday, the rats of the New York City subway system received another shot across the bow from the Metropolitan Transportation Authority.

"I want to warn you," Mark Lebow, chairman of the authority's transit and bus committee, said at a public meeting at the agency's Midtown Manhattan headquarters. "We're going to discuss rat sterilization."

The authority detailed its plans on Monday for a pilot program intended to curb the fertility of female rats, pledging to test a product — administered to rats orally — that accelerates natural egg loss and sterilizes the animals permanently.

"This technology, if successful, could complement our current strategies of poisoning and exclusion for rodent management," Thomas Lamb, the chief of innovation and technology for New York City Transit, told the committee.

The authority's partner in the endeavor, SenesTech, a company based in Flagstaff, Ariz., has conducted research in Laos, India and the Philippines, often in agricultural communities where rats pose a threat to rice farmers.

But Loretta Mayer, SenesTech's co-founder, said the work had been largely untested within transportation networks. "The only transportation, to my knowledge, that has ever been impacted has been the rickshaws of Indonesia," she said.

She added that researchers would draw explicitly on their "knowledge base of the ecology of the New York City rat." Sterilization products will be placed in bait boxes inside the authority's trash rooms.

The authority said that the typical city rat, known as the Norway rat, reaches sexual maturity at 8 to 12 weeks and can have as many as 12 pups a litter and as many as seven litters a year, "depending on refuse and track litter access." The rats' typical life span is 5 to 12 months. There is no reliable estimate of the subway rat population, transit officials said.

The authority's chosen remedy, called ContraPest, is not a contraceptive but irreversibly sterilizes female rodents by targeting the ovarian follicles that lead to births.

Dr. Mayer said the product posed no danger to humans. "I've been studying this compound for over 22 years," she said, "and I probably have the highest incidence of pregnant graduate students of anybody in academia."

A committee member asked what would happen if a person ingested the bait. "Well, it's quite sweet, quite salty and there's a lot of fat," Dr. Mayer said. "She would probably gain weight from the fat."

One challenge, the authority said, was offering the rats a bait that they might prefer to the subway system's daily treasures — half-eaten gyros and chicken fried rice, stale pizza and discarded churros.

According to a fact sheet distributed by the authority, rats would need to consume roughly 10 percent of their body weight in ContraPest for 5 to 10 days to become sterile. If they do, litter sizes will shrink within four weeks, the sheet said, before fertility is lost entirely. If a rat ingests ContraPest while pregnant, her offspring are likely to be born without complications but female pups are often sterile, the authority said.

The authority has long explored ways to chase its rats away, including a recent push to remove trash cans from a small number of stations in an effort to reduce garbage in the system. But a report released last week by the Straphangers Campaign, a rider advocacy group, found that riders had a roughly 1 in 10 chance of seeing a rat while waiting for a train.

Mindful of the rats' resiliency through the years, the authority's team cautioned that expectations must be managed accordingly.

"In the words of Albert Einstein," Dr. Mayer said, "if we knew what we were doing, they wouldn't call it research."