Update To clarify for everybody who suggests that I just give more food and attention, or arrange myself with him going out more:
- He is not 'going out more'. He is not here. After a life spending more time at home than outside, he suddenly went missing for 6 days. I returned him home, locked him up for 4 days, then let him free. He returned for a short daily visit for the next 3 days, on the third I wasn't home. He hasn't returned since (it's been 4 days now since his last appearance) and I don't expect him to come back again of his own accord.
- In the time after I caught and returned him, I did give him more food, snacks and attention than usual. He enjoyed it, but that didn't stop him from moving out again.
- I can't tempt him with food. As soon as he got the opportunity to go out again, he basically stopped eating here even though I offered a variety of food.
- He isn't on a long expedition, he spends some time every day in a garden 100 meters from here, but doesn't bother to come to my home.
About 20 months ago, I adopted a kitten, almost 4 months old, trapped with a feral mother. I neutered him at 6 months old, and let him roam at about 10 months old. He has a cat flap and is free to come and go. He's a very human-friendly cat, letting new people pet him, but quite afraid of other cats, not defending his territory and preferring to hide or run away when he sees another cat.
Up until last month, he was a homeboy and slept the whole day at home. I fed him wet food maybe 3-4 times a day - we didn't have exact hours, he just asked for it when he was hungry. He usually went out at night, and for a couple of hours once per day.
Three weeks ago, the weather turned warm. Suddenly, the cat went missing. I was already starting to mourn him, thinking that he must have been hit by a car, but started searching and on the sixth day, I found him in a garden two streets away, the owner said he has been visiting there a lot.
I kept the cat inside for four days (he was very unhappy about it!) and let him roam again, now with a transponder attached. I live at the edge of a large green area - there is a monastery with a large surrounding land holding, and beyond that, a forest starts - and I saw that while my cat does visit a few gardens, he spends most of the time in the meadows and forest, and walks about 15 km per day. My house is at the very far corner of his territory. I think that it's not the case of other people feeding him, but that he is surviving on his own hunt.
He started returning for a couple of hours per day, sometimes eating, sometimes ignoring the food and just cuddling and sleeping. This lasted about a week, then I had to travel for three days. He only returned the first day, then disappeared again and has not been inside the house. I returned yesterday and called him from my patio, but he didn't return.
I will now go look for him again, and probably be able to catch him, since I know where he goes, and the owner of that other garden can help. But I'm not sure what to do after that.
One person advised me to keep him inside for six weeks. I would hate to do that, since 1) he suffers when he can't go out, and 2) my yearly vacation is upcoming, as well as a couple of weekend trips, and I don't want him to be stuck alone in the small flat. Also, the vet and a couple of experienced cat owners, one of whom knows my cat, advised against it.
Is there something I can do to convince the cat to continue living here? I'd like to see him return at least once per day, ideally also spend some hours here.