I dont know were they come from. I have had 2 so far this year. A little gray cat (dunno age) and an orange stripped one. I set a havahart trap for a groundhog I had under the barn and next day I see this little gray cat in it. I figure it is a feral cat and when I open the cage it will latch onto my leg like a lion. So I back way off and lift the door open staying as far away from the opening as possible. Instead of bolting for the woods it slowly walks out turns and starts rubbing on my leg purring lol. I say "Welp guess I got a new mouse killer". Then one day it just disapeared. Last month I saw the orange one out by our pond. I put food and water out for it and it hung around for a week then gone. Cats are great for rodent control around the farm and the cost of cat food far exceeds thier mouse control. Wish I could get them to stay. If I had to guess I would say the coyotes are getting them.