How not to trap a feral cat

Every year this same feral cat decides to use our backyard to have her babies. So as soon as I heard her moan all day and all night (she was in heat and she was so loud we couldn't sleep--even with the windows closed) I decided it was time to call Animal Control.

After learning the trapping rules I decided to do a test run and set it up with no food or water. The next morning I woke up to this pleasant creature:

It must have been an adolescent opossum. And it was quite the cozy home for him, cause it took about 5 minutes to coax him out of there. The rest of the week I tried to persuade the cat with tuna fish and water, but I just couldn't catch anything. Oh well. Hopefully someone else caught the feral cat. Either that, or she figured she just couldn't have her kittens with a curious little opossum nearby.