Scientists conducted large-scale observations of animal behavior in the city and concluded that, contrary to popular belief, cats are not very good at catching rats.
This was the first study in which scientists have documented interactions between street cats and rats. Researchers chipped rats living in areas with large numbers of stray cats and observed their behavior for 79 days. During all this time, the rodents managed to avoid the “hunters”: they were captured only twice during the entire observation period. The results of the work were published in the journal Frontiers in Ecology and Evolution.
Synanthropic, meaning living next to humans, rats really do a lot of harm to humans. They eat and damage various goods, sometimes damage electrical networks and can spread infectious diseases through bites. So, in the United States, for example, about 14,000 people suffer from rat bites each year. Authorities around the world are taking action to reduce the rat population in cities. Basically, animals are poisoned or frightened with the help of special devices. Another method that city authorities sometimes consider is to breed cats in cities that would catch rats and promote their breeding.
However, scientists now argue that this is an ineffective method. In addition, it also has unpleasant consequences – the growth in the number of homeless cats in cities is not doing the city dwellers any good either. Instead of rats, say the researchers, cats are more likely to catch smaller, more helpless prey, such as birds. Their uncontrolled extermination can shake up the city’s ecosystem. As one of the study’s authors, Michael A. Deutsch says, so far no one has provided complete data on the number of rats killed by cats in cities. Therefore, scientists decided to fill in the gaps.
The team of researchers has been observing for some time a group of rats living in one of the districts of New York, at the city’s waste disposal center. Microchips were implanted in 100 individuals, with the help of which the scientists observed their behavior. After the cats were brought to the center to control the parasites, researchers set up cameras and monitored recordings to track how cats perform their function and how rats change behavior when they are present. During 79 days, 306 videos were shot. Despite the fact that 60 cats were active in the rat colony, only 20 cases of harassment, three attempted murders and two successful murders were recorded.
Recordings of video cameras installed at the New York waste disposal center during the experiment / © Frontiers in Ecology and Evolution
The rats, in turn, changed their behavioral tactics and began spending less time in open spaces and generally hid in shelters. Scientists say the study doesn’t downplay cats’ ability to catch rats at all, but clarifies some aspects of interactions with animals. To successfully catch a rodent, a cat must be hungry and have no other easier food source. Thus, the feasibility of using cats to reduce the rat population in cities is questioned, as predators can find other foods in such places.
Source: Frontiers