You can try make a go of it as is, but if there actually is anything out there, finding out could be at the cost of a chicken or chickens.
Happen to have deer cams? You could monitor the area at night to see if anything comes lurking.
Hiya, and welcome to BYC! :frow
I agree with the electric fencing ideas from @sourland and also 1/2” hardware cloth buried down about a foot prevents diggers.
If you’ll be moving that around, you can bend it at the bottom to come out about 18” and then pin it down with heavy duty tent...