I will say I have no experience with possums, but I have a lot of experience with the other predators, and they will come back. Once I had a coon leave me a note: "Please bring BBQ sauce, tired of them plain!" When I finally got him trapped, the trapper said it was the biggest coon he had ever...
I agree the possum will be back. I have certainly fed my share of the wild life, so aggravating. I agree with sword spider. Chickens hate change.
Best get the possum.
Mrs K