As long as the weather is nice, you have time to continue making "friends" with them via feeding. Put the food out, then sit a short distance away. Get them used to your presence. Maybe you have a small enclosed porch that you can lure them into, rather than a trap? the trap seems to scare strays. I have taken in 5 foundlings in all; but never had to use a trap so I can't really help on that part of it. With the healthier ones, I just kept making friends with no attempts at capturing. When I felt they were letting me get close enough, I went out with an old sweatshirt (to protect me from scratches) and caught them first try. With the sickly ones, it is just so easy to pick them up. But also, each time I have done this, it has been ONE cat. I am sure other PTers will have more helpf ro you. Good luck.