Scientists Found Out A Smart Way To Track All Rats In New York

Wild mice are considered the most troublesome animals for urban development. They nibble on anything on the road, spread diseases, start fires and hinder the movement of transportation vehicles. It is estimated that more than $300 million a year has been spent on this type of animal. Despite their negative consequences, humans do not have much information about urban rats. This is because they have many different behaviors than lab rats. Moreover, scientists are also not allowed to release pests outside the laboratory for further studies. 

Not to mention, letting urban mice may destroy city properties as well as control them from causing other problems is impossible for scientists. But now, there is a new method proposed, which is a trick to track rodents through the use of other mice. The scientists found that the rats could be lured, baited or pushed out of their positions with the help of pheromones in the smell of other mice, according to publishing from Oxford University Press in The Journal of Urban Ecology.

In a year-long experiment, urban rats were trapped and implanted microchips into a waste recycling center in Brooklyn, New York. To prevent the GPS signal from being easily lost when the rats move in a chaotic urban environment, the scientists also applied additional radio frequency identification sensors to them. 

The scientists also placed male and female pheromones on the sensors and near the sensors. They would replace the sensors every two weeks. In addition, they placed these devices in safe areas such as sheltered areas that rats are frequent to appear, and even more open and dangerous areas such as places where the rats can easily catch prey. All conditions and potential risks would be considered by scientists.

Results showed that the rats responded differently to male and female scents. In conditions where the risk was negligible, the mice responded to sensors that smelled male instead of female. They quickly passed through safe and dangerous areas that have male scents, then exited immediately. Despite this, they were more attracted to the female scents, expressed by a higher number of visits per day (0.2 visits/day compared to 5.02 visits/day). 

As such, attractants near sheltered areas will be useful in attracting the rats, while deterrent scent will be useful in visible areas. This helps increase the understanding of the preferred scents in mice, and pave the way for the development of future urban wildlife management solutions, in addition to normal trapping or immuno-contraceptives methods.