Climate change may cause more rats in cities, study warns

A new study has found that climate change could lead to an increase in rat populations in cities around the world. Researchers from Richmond University in the U.S. discovered that warmer temperatures, especially during winter, allow rats to stay active longer and breed more, leading to a rise in their numbers.

Professor Jonathan Richardson and his team studied data from over 200 major U.S. cities and three global cities—Toronto, Tokyo, and Amsterdam. They found that in 11 out of 16 cities, rat populations had grown significantly, with cities like Washington, D.C., San Francisco, and New York seeing the biggest increases.

Rats are a problem for cities because they damage buildings, contaminate food, and can even cause fires by chewing through wires. They also spread diseases to humans. The study warned that unless action is taken, the rat problem could worsen as temperatures continue to rise.

These findings were published in the journal Science Advances.