Rat populations in the city are booming as the earth preheats.

As the earth warms up, many pest species have been expected to flourish, and now a study of 16 major cities found that rat populations are growing the fastest in areas with the fastest average temperature.

It is very difficult to estimate the number of rats in the city. Jonathan Richardson His colleagues did not try this at the University of Richmond in Virginia. Instead, they felt how the population is changing by looking at the number of dissatisfaction with the rats recorded by the city.

In the United States, this information was often available openly, and the team was able to contact the city officials to get data from other regions. Researchers included cities in the study only if at least seven years of data can be used and the collection method has not been changed. As a result, data left for 13 American cities as well as Tokyo, Amsterdam and Toronto.

Their analysis is the number of rats in New Olians, and stable in Kentucky and Tokyo Louisville, Dallas and St. Louis, and the fastest growing in Washington DC, San Francisco, Toronto, New York, and New York in other 11 cities. Amsterdam.

Richardson and his colleagues have looked at some of the elements that can explain the trends. They have found that the most powerful associations over the last century are related to the average temperature increase. Next, the most powerful connection is related to urbanization, followed by satellite photos and then followed by population density. The city’s GDP did not show a connection with rat trends.

In cold cities, the number of rats is known to fall in winter and the peak in summer, so the population is increasing when the temperature rises, researchers say. More rats are more likely to cause rotten mice, such as leptos pira, also known as the Weil ‘S Disease.

According to the survey, the city needs to make more effort to control the mouse population as the earth warms up, and Richardson says it is the most important single measure to reduce food supply.

“It is an approach that has the greatest influence on rat control to secure food waste and not access to rats,” he says. “We have a pilot in New York City -Last -Last -Measured in the number of rats.”