ScienceDaily (May 26, 2011) — Researchers (and some cat-owners) wanted to know: What do feral and free-roaming house cats do when they’re out of sight? A two-year study offers a first look at the daily lives of these feline paupers and princes, whose territories overlap on the urban, suburban, rural and agricultural edges of many towns.
Jeff Horn, a former graduate student in the department of natural resources and environmental sciences, and colleagues collaborated on a two-year study of owned and un-owned cats outdoors.
The study used radio telemetry and a sophisticated activity-tracking device to capture the haunts and habits of dozens of owned and un-owned cats living at the southern edge of Champaign and Urbana, neighboring cities in Central Illinois. Together, the 42 adult cats originally radio-tracked for the study.
“There’s no (other) data set like this for cats,” said Horn. He conducted the study for his master’s thesis at the University of Illinois.
As expected, in most cases the un-owned cats had larger territories than the pet cats and were more active throughout the year. But the size of some of the feral cats’ home ranges surprised even the researchers.
One of the feral cats, a mixed breed male, had a home range of 1,351 acres, the largest range of those tracked.
Like most of the feral cats, this lone ranger was seen in both urban and rural sites, from residential and campus lawns to agricultural fields, forests and a restored prairie.
One of the feral cats in the study, a mixed breed male, had a home range of 1,351 acres.
“That particular male cat was not getting food from humans, to my knowledge, but somehow it survived out there amidst coyotes and foxes,” Horn said.
The owned cats had significantly smaller territories and tended to stay close to home. The mean home range for pet cats in the study was less than five acres.
“Still, some of the cat owners were very surprised to learn that their cats were going that far,” Horn said. “That’s a lot of backyards.”
The pet cats managed this despite being asleep or in low activity 97 percent of the time. On average, they spent only 3 percent of their time engaged in highly active pursuits, such as running or stalking prey, the researchers reported. The un-owned cats were highly active 14 percent of the time.
“The un-owned cats have to find food to survive, and their activity is significantly greater than the owned cats throughout the day and throughout the year, especially in winter,” Horn said. “These un-owned cats have to search harder to find food to create the (body) heat that they need to survive.”
The overlap of feral and pet cat territories outdoors spells trouble for the environment, the cats and potentially also for the cat owners, the researchers said.
In an earlier study, co-author Richard Warner, an emeritus professor of natural resources and environmental sciences at Illinois, followed the cats of about two-dozen rural residences over several years.
“Two of the leading causes of cat deaths in that study were other cats and disease,” Warner said. “And both of these leading causes of death are sitting here waiting for these owned cats outdoors.”
Even though pet cats have relatively small ranges and are active only in short bursts, Warner said, their impact on wildlife in the immediate vicinity of their homes is likely much more intense than that of a feral cat that wanders over a larger territory.
