My New Trap vs The Neighbor's Cats

I'm not sure how ethical this is, but I'm to the point I don't much care.

I've added 9 new cats to my family in less than 2 years. Kittens just keep showing up at my barn at 4-8 weeks of age. Three litters so far, all black or tuxedo, all somewhat tame. I asked the neighbor if they were missing some kittens. Nooooooo. According to them, their cats all stay down at their barn. They go deaf when I ask them if they've been altered.

So I bought a new trap, put it in the barn and started baiting it with soft food in the locked open position for a few days. The first night I set it I caught an all black male, maybe 7-8 years old by the vet's estimate. Had him neutered, vaccinated and let him go. Caught him again two nights later. (The dummy) Then I caught a female, kind of a dark siamese with white bib and feet. Vet estimates she's at least three. I think this was the baby factory, but I can't be certain. I guess time will tell.

I know these are the neighbors cats because I've seen them out in front of their house. (with the people) I can't get near them. I wish I knew if it is the mother cat(s) who are bringing the kittens over or if it's the neighbor guy. I would not be opposed to setting a trap for him either. I suppose the neuter thing is out of the question though.

I kind of wonder whether they'll say anything to me, or even notice. I kind of doubt it. But from now on, any of their cats that pay a visit to my barn will be going home with a new haircut.

We live outside the city limits, as do the neighbors. I was actually afraid to push the issue with them because I thought the neighbor might shoot or poison them himself.

Since all my cats are altered and indoors, I know this problem is coming from somewhere else. The first litter I thought was just dumped. The second, which looks exactly like the first, made me go The third was when I bought the trap. Fortunately, the kittens have all been relatively healthy. I didn't test the ones I trapped, but nothing obvious showed up when they were examined. I had them vaccinated, although I don't know the one shot will provide enough protection. Better than nothing, I suppose.

I've seen both of the ones I released at least once since in our barn. I've been putting out a bowl of dry food daily thinking that if the altered ones stick around, they might keep others from coming across. Plus, I wanted them to have something to eat while they recouperated. I don't know if the neighbors even feed them. Does that sound like a good idea, or bad?

It's good to know I'm not the only one who takes liberty with the neighbor's cats.

We've decided to continue feeding. We both go to the barn a couple times a day, so if we see anyone new we'll start putting the trap out again. It's not cheap, but testing, spaying and vaccinating those last nine kittens wasn't either. Our only concern is drawing other animals to the barn. You know, the unwelcome ones that are also black and white. I have a board across the top of one stall that they can either climb to get to, or jump down from the loft. I suppose it's only slightly better than putting it on the floor, but at least they'll have to work for it.