Personally I think the critters are there all ready,you just dont notice them as much till you have chickens and are protecting them..Since Ive always been aware of the wild life ard us,we had fox,coyotes,oppossums,raccons,hawks,owls,copper heads,timber rattlers and black n garden snakes and deer a plenty long before my girls.I do agree that your coop being secure makes alot of difference.We had a garden shed and it was a "play house for the kids" then back to a shed and now..."our coop" Prior to the girls we had a wood chiuck that had made a home under the shed,we totally forgot abt that and when DH converted the shed to the coop he also put the heavy guage wire under the ground and nailed it to the base of the shed and 8 ft privacy fence that goes ard from the back right corner to the front left corner of the shed.This is the "run"..aka"play yard...It is also all along the top.Nailed to the top/inside of the privacy fence,so nothing can swoop in..I lock the girls up at night ard 7 pm in the fall and 8;15 pm in the summer and let them out ard 6 ish in the am.I do check on the during the day and we go out and sit w/them and feed them treats.Even though we have over 1 1/2 acres we cant let them free range. One night I went in to do "lock down" I picked up the board for the trap door and there was a opossum in there behind the wood used for the trap door...Thought I was gonna....p...my pants..Of course that was the night I had no kids home,no phone w/me and no gun w/me...Yikes!! I used the boared n scurried him out ...when my son got home a hr later we went on a possum hunt w/no luck...Next day,we filled in the hole from the wood chuck,put big bolders ard the base of the shed and added more heavy duty guage wire ard the base.Did find the spot he entered and it wasnt nailed secure in a few places..My neighbor spotted a coyote w/mange last week n gave me heads up,there is also a mama fox w/babies in the field across the road.So I do believe there is already the wild life ard,but they can smell "chicken" for miles..Just make sure your coop is secure,keep a eye on things and do the best you can.I love my girls and am so very happy we have them,they are great and very spoiled..We are planning on more in the spring.Good luck to you.Hope that helps.Chickon baby.