The Sylvester and Tweety myth

New research shows that Sylvester may have been much more of a threat to Tweety than Looney Tunes ever let on. Domestic cats are now believed to be one of the biggest imminent dangers to resident bird populations, and even possibly other nearby wildlife.

“America’s cats, including housecats that adventure outdoors and feral cats, kill between 1.4 and 3.7 billion birds in a year,” according to research leader Peter Marra of the Smithsonian Conservation Biology Institute in Washington, D.C., quoted in ScienceNews magazine. Due to a large research study that analyzed hunting habits of cats from around the world, scientists are reconsidering their previous estimates.

The cat is out of the bag and ready to strike. Graphic by Kate McHugh.
The cat is out of the bag and ready to strike. Graphic by Kate McHugh.

To conduct this study, researchers had to consider how many cats are currently living in each location. It all comes down to a relatively simple math problem.

“Roughly 114 million cats live in the contiguous United States, 84 million of which share people’s houses. Forty to 70 percent of those household cats do at least some roaming outside. Between half and 80 percent of those outdoor cats hunt,” said Marra and his colleagues.

Estimating the number of land birds is a bit more challenging, but Marra believes the number to be “between 10 billion and 20 billion adults.”

Putting a stop to this hunting and the rising cat population sounds like it would be a simple enough solution, but it’s much easier said than done. Catching and neutering stray cats to prevent population increase is, “simply too difficult, time consuming and expensive,” said Stanley Temple, a conservation biologist at the University of Wisconsin-Madison.

Rounding up and killing stray cat populations is also pretty ineffective, and it doesn’t sit well with animal rights activist groups. So how are we supposed to control the problem before some bird species find themselves on the endangered animal list?

Marra suggests that the answer lies with “responsible pet ownership.”

“Even though full-time outdoor cats may be the bigger problem, cats with indoor homes still catch some 1.9 billion wild animals a year,” he said.

Marra and his colleagues hope that these new findings will help to increase the conversation about conservation efforts, which haven’t been taken very seriously in the past. Cats aren’t often seen as powerful predators, given all the other factors wildlife has to deal with on a daily basis. But that conversation might be starting to change.