National Geographic's Carrie Arnold notes a recent environmental-impact study of feral cats suggesting that they tend to hunt relatively small animals lower on the food chain.
Interview at the site.
Cats, already the overlords of the Internet, also reign over Jekyll Island, a small barrier island off the coast of Georgia.
The island is home to 150 free-ranging cats, which is about one cat for every five people. While the feral felines can help control the numbers of rats, mice, and other animals considered pests, they can also prey on other local wildlife—including, most controversially, birds.
A 2013 study, for instance, estimated that free-ranging cats are responsible for killing billions of birds and mammals in the continental U.S. every year, including possibly up to 3.7 billion birds. The study sparked major debate among both bird and cat groups. The American Bird Conservancy has said "the carnage that outdoor cats inflict is staggering."
Since Jekyll Island is a popular stopover for many migrating tropical birds, wildlife biologist Sonia Hernandez at the University of Georgia wanted to see whether the island’s feral cats were preying on birds.
Enter the KittyCam: A small, collar-mounted video camera that records life from a cat's point of view. By putting KittyCam on 31 feral cats for a year, Hernandez and her team gathered many hours of footage that let them see exactly what the island’s felines did—and didn’t—catch.
Interview at the site.