We have not had this problem before. They are birman cats so they used to be indoor cats, but 5 years ago we moved to a house that's rural and I started letting them out in the evenings and they would usually be back within the hour. In the summer months they ask (loudly and persistently) to go out in the mornings too and if I'm home I let them out then.
Anyway, this summer is different to the other 4 because in the last 2-3 weeks they have been bringing home dead and live mice. It is horrible. The live ones are completely terrified (understandably) and it takes ages to get them out.
They both wear collars with bells when they go out and always have. Does anyone have any advice on other ways I could stop this?
To be honest I'm thinking of keeping them in for a while.