What's with the dead possums??

I have found another dead possum in the yard this morning. This is the 2nd one in the last week and a half I have found. We have been here for 18 years and I have never had a dead possum, and now 2 in 2 weeks??? I don't know what's going on. This one had been dead for a little while.... it was not pleasant...they have definitely been poisoned, with ratsak I would say... you can tell when they have been poisoned, as they always have a little hole in their tummy..... the poor little things...they are so cute.... we have ratsak in our shed, but it is in a sealed rat trap and wildlife and dogs, cats etc can't access it, so I think a neighbour has had some ratsak around. I just wonder why I always find them when Damian isn't home to be the one who has to pick them up and wrap them up in paper....just my luck.... I know people get annoyed when they have a possum in their roof, I just wish they would build them a possum nest in a tree, instead of poisoning them....so sad.....