A recent study on domestic cats revealed the secret life of the feline when not around with humans.

Researchers at the University of Georgia strapped small and light-weighted video cameras on 60 domestic cats in Athens, Georgia to find out their lifestyle when not around with humans. Experts tracked the feline movements from November 2010 to October 2011 for their project 'Kitty Cams' in collaboration with National Geographic.

The camera was also fitted with a small LED light to take videos in the dark. The cats were allowed to roam outdoors freely for some time both during the day and night.

Based on the footage collected, researchers found that the cats were indulged in killing more wildlife than previously thought. While 41 percent of the prey consumed was reptiles, 25 percent was mammals. Birds made up for nearly 12 percent of their prey, a report in Daily News said.

"The most surprising finding was that cats were actually killing more reptiles and amphibians than what's talked about in the literature, which focuses on birds," Dr. Sonia M. Hernandez, one of the study's researchers from the University of Georgia, told the Daily News.

Besides their eating habits, experts also found that more than 85 percent of the cats were involved in taking risks such as crossing the street, eating unknown substances, entering small spaces where they might get trapped and facing other cats. While male cats were largely involved in taking such risks, the old feline were the least risk takers.

Researchers said that if the data is used to calculate the cats' prey across the nation, the overall kill will be more than four billion animals per year, including at least 500 million birds. Interestingly, it was also noticed that four of the sixty cats had another family which they had adopted. They found that the four entered another owner's house for their food and care.

Kerrie Anne Loyd, lead researcher of the project, has posted a set of photos and videos of the cats on her website. To take a look at the photos and videos, click here.