You can buy sonic fox repellants but I have no idea if they work (although the adverts all claim they do ). Alternatively could you invest in an electric fence?
There are old fashioned ideas of male urine being sprinkled around the border to your property or bundles of human hair (if you know any hairdressers they may be able to provide some for you) but again I do not know if they really work.
Foxes are very hungry at the moment so will risk a lot of things in order to get food and now they know you have some easy pickings it may be best to keep them in their run for a while .
So sorry you lost your girls. Really upsetting. My sister lost her first hens to the blasted fox.
Urine and hair don't work. Sprinkling chilli powder very thickly works for a while but if you forget to keep it up or it rains it wears off. Not sure if it would work at all if the foxes are really hungry. Sonic option sounds a bit of a gamble to me.
We tried prikka strips on the tops of our 6 foot fences and the b.....ds still scramble over, strips and all!
So far keeping our ladies behind an electric fence has kept them safe during the day and at night they are locked up safely in their eglu cube. We have watched quite happily at the foxes who have had experiences of the shocking kind!! Wonder if hubby could up the power for a couple of days, fried fox?
Did hear of an electrician who had his girls taken and he rigged up one of his dead chickens to the electricity supply and waited for the fox to come back and zap!
We have had to do stop letting our ladies free range as the fox was a metre away from our hens one Sunday lunch time. I only left the kitchen, where I could see them, for a couple of minutes to collect a cook book and when I came back my husband was hurtling down the garden brandishing the spade. Since then we keep them behind the electric fence in a generous sized part of the garden.
It was terribly upsetting watching the girls come running up in expectation of being let out and then waiting at the gate willing me to let them out. They would do this everytime I went out into the garden. I felt so damn guilty. We couldn't risk letting them out when we were in the garden either because if the doorbell went and i had to answer the door, it only takes a few minutes for a fox to strike.
Also the girls get used to coming out in the garden and expect it. If it doesn't happen they create a fuss and make me feel guilty again.
AM a bit twitchy at the moment as my sister has had her electric fence breached by the fox and her last chicken taken.
I know of someone who had one of her hens taken and she bought a fox trap and then took the fox on a long holiday and let him go. This could be an option although I believe it is illegal to let the fox go once it has been caught and it should be shot. That is what I was told when I made inquiries into buying a fox trap.
I also believe that there are pest control companies who will deal with the fox problem for yo but you have to pay and some charge you a lot of money for trapping the fox then letting it go again. Then you can have the creature finding its way back home.
Hope you find a solution that is right for you and the family. Always incredibly upsetting for the children.