Mongolia is imposing a three-year ban on hunting marmots. The reason behind the decision is preventing the bubonic plague from spreading to people, and determining the current range and population size of marmots in the country.

The bubonic plague is a bacterial disease that is spread by fleas living on wild rodents such as marmots. The disease can kill an adult in less than 24 hours if they are not treated in time, according to the World Health Organization.

Currently, 17 out of all 21 Mongolian provinces are at risk for the bubonic plague, the country’s National Centre for Zoonotic Diseases said.