All around Boston at night, tiny hot mics are capturing hours of conversations under the radar. Scientists comb through the recordings, with AI making the job easier. Rest easy — your secrets aren’t the juicy stuff they’re after. The scientists are recording the city’s rats. The system detects and removes human speech, leaving the researchers to focus on rodent chatter. The project is a collaboration between Basis, a nonprofit that uses AI to tackle complex problems, and Boston city officials, with assistant commissioner of environmental services John Ulrich and his team at the helm. By matching recorded rat calls with video of their behavior, the team hopes to uncover how the rodents interact and navigate their surroundings — knowledge that could help the city prevent infestations rather than respond after they take hold.
Linger around Downtown Crossing at night or circle Frog Pond at the edge of Boston Common, and you’ll spot rats peeking under planters or darting across the path to duck into a buttonbush shrub. In 2021, Beantown even led the nation as the “rattiest” city. Data from the mayor’s office shows that in 2025, the city had responded to 5,957 rodent-related 311 calls by early December. At the National Urban Rat Summit that Boston hosted this year, experts talked eviction strategy. Instead of swooping in with traps and trained ferrets, one of the ideas was to gather intel on how rats respond to control efforts, using changes in their calls and activity to gauge whether the measures are working. Northeastern Global News spoke to experts, including animal behavior and urban affair specialists, about Boston’s rat problem.
