Ever wondered what your cat gets up to when you're not keeping an eye on him?
Scientists have come up with a way to keep tabs on pet cats when they're out and about to find out what they get up to.
Leah's been finding out more...
"I'm a big dog lover. Growing up we always had dogs as pets and recently I've been looking after a Yorkshire Terrier called Belle, for my cousin.
So when I found out I'd be spending the day with some tabby cats I was looking forward to being close to cats for once.
Thomas and Anna's cats bring them unwanted gifts, like dead mice and birds!
When we arrived, Fuzzy and Poppy seemed happy to see me because they purred loads and hung around my legs. I helped serve up their tuna and chicken lunch, which looked pretty yucky but they tucked in right away.
Fuzzy and Poppy's owners Anna and Thomas told me the moggies often bring home nasty surprises, like dead mice and small birds, which can be pretty horrible.
It's a natural reaction for your cat to catch its dinner, but it could be bad news for the wildlife in your back garden.
It's hoped the tags will help experts learn more about cats' behaviour
Now for the first time scientists have fitted some cats with logging devices to track where cats go on the prowl.
The researchers from the University of Reading say they can even detect where and when they go in for the kill.
There are about nine million cats in the UK and it turns out an average cat kills about 10 bits of prey a year.
Experts are now waiting to find out what information they get from the cat tracking kits.
It's early days, but it's hoped they'll be able to find out for definite whether cats are having a big impact on our wildlife."