I would go over there and say, the next time your birds are on my property I am going to shoot them, just like you'd shoot my dog if it got on your property. This is your last warning. And if they come back, just coop them up and keep them.
If you just take them, I'd be afraid he'd accuse you of stealing. Warn him first, like he rudely warned you when you moved in about your dogs. They get what they gave so heres your chance.
If you just take them, I'd be afraid he'd accuse you of stealing. Warn him first, like he rudely warned you when you moved in about your dogs. They get what they gave so heres your chance.