We moved into a new house in April. Next door (who are lovely friendly people) have 2 neutered male cats, one of which seems to have taken a dislike to my neutered female cat.
This boy cat is an ex-farm cat and very territorial. He sees our garden as his own. My girl is quite territorial herself and although she doesn't stray far she defends our garden as her own. There's been quite a few bust-ups between them in our garden (always instigated by him, she defends herself with a great deal of noise). Although it hasn't progressed beyond the usual cat posturing and screaming, I've had to step in several times and chase him off. I've seen him run the full length of our garden to have a go at her. He also has a habit of trying to get into our house to eat her food (we're not allowed a cat flap so I have to keep the back door open for her).
Are they just figuring out the hierarchy? Should I actually be stepping in at all? My cat doesn't seem stressed but being a soft mum I hate seeing these fights.