My geography is abysmally bad, so don't laugh! Is Kim of Kimlovescats too far away to help you? I know she's not really close to you but do you think she would be willing to take care of the kittens if you scooped them all up and took them to her on the weekend? The chances of them becoming coyote fodder as they start to move away from mom on their own is going to get worse and worse. Mother Nature's way, of course, but not something you want to have happen in your own garden to kittens you've already seen.