Science Says Cats & Dogs Need Each Other to Scare Off Rodents

A recently published study suggests that it takes both dogs and cats
to keep rodents away.
Photo by Michael Pettigrew, via Adobe Stock.

Most of us think that having a cat around will keep mice and other vermin-style critters under control. But is that true? Until recently, no one could say for sure, as all we had to go on was anecdotal evidence—people say that having a cat will keep mice away, so we tend to believe it. Well, a study recently published in PLOS ONE concludes that cats alone have only a small effect on rodents. If you want mice and rats to avoid your homestead, the study says, you’d better have cats and dogs.

Hunting styles of cats and dogs

I know, it’s distressing, right? Cats have owned the trophy for vermin-killing for centuries, and now suddenly we might have to share it? Almost unthinkable!

But the study authors point out that cats and dogs have different hunting styles. Cats are solitary, ambush-style predators, whereas dogs hunt in packs in the wild and chase prey over long distances. Both cats and dogs are known to eat small mammals such as mice and rats, but dogs are more likely to feed on trash than on those tasty little creatures. (And here I shall refrain from making a rude comment about dirty, trash-eating dogs. Oops! That just slipped out. Sorry, dogs.)

Cats, dogs, and rodents on rural homesteads

That little dot inside the circle is where
Swaziland is. The study was carried
out on 40 rural homesteads there.
Map by Alvaro1984 18
[Public domain], via Wikimedia Commons.

The study was conducted in four villages in Swaziland (that’s in southeast Africa). Forty rural homesteads were selected: 10 homesteads with cats, 10 with dogs, 10 with both cats and dogs, and 10 with neither. Homesteads with domestic cats and/or dogs typically had one or two cats and between one and four dogs, all of which were free to roam around the buildings and fields.

The researchers needed a way to measure rodent activity at the different homesteads. They decided on white ceramic tiles that were blackened with soot. These tiles were set out at night, and when rodents walked on them, they left little footprints behind. The more footprints on a site’s tiles, the more rodent activity at that site.

White ceramic tiles were blackened with soot and
set on the ground overnight to measure rodent activity.

(a) tile blackened with soot; (b) marked with rodent footprints.

The more footprints, the more rodent activity.

Photo via PLOS ONE.

The results showed that homesteads with just cats or just dogs had less rodent activity compared to homesteads without cats or dogs. But—and this was shocking to me—the difference was not really significant. The places with greatly reduced rodent activity were homesteads with both cats and dogs. Perhaps, the authors suggest, when rodents come across a homestead with two different kinds of predator, they decide that place is just too dangerous. They would rather leave behind whatever food is there because there’s too great a chance that they will be eaten while they are eating. The cats and dogs together create a “landscape of fear” for the rodents.

We wonder if a similar study would produce the same results in, say, Nebraska. As a cat, it is embarrassing to think that we might need the help of dogs to give rodents a really good scare. One can only hope that future studies will show that it’s the cats who are doing all the real work, right?

  

Source

Mahlaba TAM, Monadjem A, McCleery R, Belmain SR (2017) Domestic cats and dogs create a landscape of fear for pest rodents around rural homesteads. PLoS ONE 12(2): e0171593. doi:10.1371/journal.pone.0171593