We have a fox problem too, which is the reason I became interested in PCP rifles and joined this excellent forum.
We lost one of our guinea fowl last month to a fox that was bold enough to come out in broad daylight mid-day, less than 30 minutes after my husband had just been down at the barn, and proceed to get one of our three guineas. We started out with ten guineas 12 years ago, now down to just 2
. We weren't sure if it was a hawk or fox, had a fox get one also mid-day in Jan 2023, but this time we had video evidence of the attack. Kinda amazed that the fox wasn't able to get the first guinea he attempted to grab. Especially since the guinea missed flying up on the barn roof and did all that maneuvering to evade Mr. Fox. They're good runners, but they are also nearly 13 years old!! Here's the video from our Reolink camera -
Red fox after 12 year old guinea fowl In all those years we haven't had fox problems, they stayed out of the guinea's field. Most of our fencing is 48in Keystone horse no-climb with 2x4in squares and we have a top electric wire. We do have a section back by a creek fenced with only high tensile wire and our game cameras pick up various critters passing through (deer, fox, etc.). All was well when they stayed in their own lane. Only in the past couple of years we've noticed them digging under the Keystone fencing at night, so we'd run some electric down across the dig spot which in the past had done the trick. Evidently they're determined to go after the guineas which I'm determined to stop.
For those that think a red fox won't climb a fence, I saw one in the guinea field after the Jan 2023 loss, ran down there and that fox didn't hesitate to go up and over the Keystone fence, hopefully getting a taste of the electric top wire in the process.
Good luck with dispatching your chicken killing fox.