Does your city feel rattier than ever? Rat numbers are shooting up and scientists say they’ve figured out why

There is a saying that you are in a big city, as you are more than six feet from mice. It is an urban legend, but scientists warn of cities around the world, it has become more radi, and the boom is driven primarily with one factor: Climate.

Jonathan Richardson, a professor of biology at the University of Richmond, decided to search in urban mice trends after seeing media reports on mice that take over cities. This tends to focus on one sites and “usually without a lot of difficult data”, as he told CNN.

He and his team decided to change that. They requested mice statistics from the 200 largest American cities by the population, but they found only 13 had long -term quality data they needed. To give more geographical scope, researchers also included three international cities: Toronto, Tokyo and Amsterdam.

The collected data spanned 12 years and consists of mice and luxury scenes and inspection reports.

And revealed “large increasing trends” in the numbers of mice on 11 out of 16 cities, according to L. TicketIt was published on Friday in the magazine of Science Advances. Washington has witnessed the capital, San Francisco, Toronto, New York City and Amsterdam. Watch only three declines: New Orleans, St. Louis and Tokyo.

The study associated with several factors, including high population density and low quantities of vegetation in urban areas, but the prevailing effect was the warmer medium temperatures.

Richardson said the mice are small mammals and are limited to the cold. The warmer temperatures, especially in the winter, give longer time to be out of research, longer, longer to breed during the year.

The warmer climate can extend the growth seasons, providing mice more food as well as the vegetation of the hiding in it. “Even food and garbage scents can travel further in the warmer weather,” he told CNN.

The increasing mice groups are a major problem for cities. Mice damage infrastructure, food pollution, and fires can start with scales through the wires. It causes an estimated $ 27 billion of damage every year in the United States, according to the report.

They are a healthy risk, too. “Mice are associated with more than 50 pathogens that affect people,” said the pest expert at Cornell University, who did not participate in the research.

Some of these can be severe, Such as the domain diseaseIt is also called a woe disease, which can cause kidney, liver damage and even death without treatment.

Richardson said there is also increasing evidence for her “huge mental health effects” on the people who live around them.

Even among the most identified cities in the study, Washington, DC, has emerged. He had 1.5 times greater growth in mice residents from New York City.

The pregnancy mark of the problem of mice in the capital is a hole that is chewed through the solid plastic trash. “The only way you can prove rodents that the garbage can put in a food position in it,” said Gerard Brown, who runs the city’s rodent control program.

Last year was the most important figure in the capital – bad news for attempts to control mice. Brown hopes that the cold in December will help the execution of the population. “The cold works as a natural pesticide,” he said.

Braun and other city officials tried a trial project to identify mice several years ago, but they abandoned it after uncomplicated results. Mice had to consume daily liquid offspring, an impossible task to ensure them.

Brown said that the capital numbers may be very high because the city encourages residents to communicate in every vision of mice.

Parsons, a field environment scientist, said general reports on mice are very useful but can be defective. He said that people usually make a call only when they see something “unusual”, not when mice expect any specific area.

Parsons added it is very difficult to determine the exact urban mice numbers. “The mice are small, hidden and are usually night.”

Richardson said that the large number of mice in some cities is not accusing the authorities’ commitment to address the problem, but efforts to reduce mice are often funded.

He said that lessons can be learned from the three cities in the study that reduced mice groups. He expelled their success until campaigns to inform the population how to avoid attracting mice and making the city resources available for help.

Richardson also encouraged the authorities to stay away from deadly control, “because it only responds to the already existing injuries,” and more thought about how to access what mice depend on, such as food waste, garbage arrival, and debris piles.

Richardson said the results are an invitation to wake up about the challenge that mice may pose in a warmer world. “If you don’t have a handle on this, you will get worse. You don’t want to be like sisyphus, pushing this rock to the top of the hill.”

In the capital, Brown said he was optimistic about the city’s battle to maintain mice under control. He said: “No one in the world believes that we will completely get rid of mice, but we can reduce it to a controlled level.” “The goal is to control and reduce.”

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