Cats are surprisingly bad at killing rats | Smart News

Cats are contradictory creatures. A 2017 study found that domestic felines – considered one of the most pervasive and environmentally damaging predators on the planet – have contributed to the extinction of at least 63 species vertebrates worldwide, but new research has been published in Borders in ecology and evolution suggests that wildcats are extremely inefficient at catching the prey most commonly associated with their urban escapades: rats.

Researchers led by Fordham UniversityMichael Parsons spent five months observing a rat colony housed in a Brooklyn waste facility, reports Matthew Taub. Atlas Obscura. Although the team started by studying pheromones, or airborne chemicals that can influence animal behavior, they quickly turned to interactions between the rat and the cat. The results were surprising to say the least: during the 79-day trial period, local cats only ambushed three of the 150 or so rats in the establishment – killing only two.

according to Science NewsSusan Milius, the researchers tracked the dead with motion-activated cameras that recorded 306 "active animal" videos. Based on these clips, scientists recorded 20 harassment events and three attempted murders (only two of which were successful). The murders took place in conditions close to those of an ambush, while the unsuccessful attempt was an open chase.

"[It was a] a very hesitant pursuit, like a stop-dance that they do, "tells Parsons to Milius. "When the rat stops, the cat stops too."

The size and ferocity of city rats may explain the incredibly low mortality rate of felines. Cosmos. The famous brown rats in New York usually weigh about 330 grams, about 10 times the average mouse weight. Given the choice between attacking a monstrous rat, a 15 gram bird and a 30 gram mouse, cats tend to opt for less difficult prey.

Atlas ObscuraTaub notes that rats sensing a growing feline presence also change their behavior, rushing in and keeping largely out of sight. As the researchers report in their study, a 1% increase in the number of cats on a given day makes it 100 times less likely that a rat will trigger camera-sensitive cameras.

New discoveries contradict popular conceptions of predation by felines. As Angus Chen notes for American scientistCats have a reputation so widespread as rodent killers that organizations ranging from Washington, DC Blue collar in Chicago Cats at work regularly release wild felines in the hope of fighting rodent infestations in urban areas.

But University of Florida disease ecologist Gregory Glass, who did not participate in the study, told Chen that cats and rats are more likely to ignore or avoid each other. .

"Once this rat reaches puberty, [it’s] far too big and nasty for the cat to treat, "he says. "You can see a lot of cats and rats getting along with each other, lying down on each other, eating in the same garbage bag."

As Sarah Zhang writes for L & # 39; AtlanticThe introduction of wild cats in urban environments can spawn a multitude of unexpected side effects. Feline feces spread a disease called toxoplasmosis, which can cause serious brain damage or even death, when it is transmitted from a pregnant woman to a fetus. Cats are also notorious bird killers – a 2013 study It is suggested that animals are responsible for the death of 2.4 billion birds a year, and this only in the United States.

Parsons tells Taub that waste management, not wild cats, is key to managing rodent populations in urban areas. The waste attracts the rats, so if less waste littered the streets of New York and other cities, the rats would moderate themselves.

"People see fewer rats and assume that it's because cats have killed them – whereas it's actually due to the fact that rats are changing their behavior," Parsons said in a statement. declaration. "The results of our study suggest that the benefits for the release of cats are largely outweighed by the risks to wildlife."

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