Tallinn collects resident tips to target rodent control efforts

The Põhja-Tallinn district government in Estonia's capital is collecting resident reports on rat and mouse activity until mid-August, aiming to direct pest control efforts toward the most affected areas. Kadri Karnau, communications specialist at the Tallinn Environment and Public Works Department, explained that the city does not keep centralized statistics on rodent numbers, since such figures cannot be reliably measured, but public observations remain useful for spotting larger colonies.

Responsibility for rodent control in Tallinn is split by area, meaning homeowners' associations and private property owners carry much of the burden. Karnau said that once a colony is found, the first step is contacting the relevant property owner or association, since the city and district can only act within areas under their own management.

The department relies on rat poison placed inside sealed plastic boxes rather than broad preventive poisoning, which would risk harming pets, birds and people. Control measures are targeted, based on identified nesting sites and movement routes.

Full eradication isn't realistic

Joosep Sarapuu, a zoologist at the Estonian Museum of Natural History, said local control efforts cannot fully eliminate rats from the city, since a vacated colony's territory quickly becomes available to newcomers. Rodents' natural wariness of unfamiliar objects, known as neophobia, also slows control efforts, as they take time before approaching new traps or poison boxes.

Sarapuu dismissed the common belief that colonies deliberately send weaker members to test poison first. In reality, dominant rats avoid new objects because they already have established routes and reliable food sources, while lower-ranking members are pushed to seek new feeding grounds and thus encounter traps and poison first.

He recommended using summer to check homes for gaps that rodents could use to enter once the weather turns cold, sealing any openings carefully, and ensuring food waste isn't easily accessible. Karnau added that keeping neighborhoods tidy is the most effective deterrent — waste rooms and containers should stay closed and well maintained, and residents should avoid feeding birds and squirrels or leave fallen food to accumulate near feeders.