We have flocks (is that the correct word?) of wallabies living wild in the UK. They escaped over the years and bred. Marsupials can breed, and then some! They have a much more efficient system of successive controlled gestation from a single fertilization than placental mammals.
The probability is that if one has been seen, there are lots of them around and about, owned by nobody. The Pennsylvania authorities had better hop to it!!
If you find something you cannot do, start doing it. Pretty soon you will find how you are doing some of it wrong and put that right. After a while, you will find you are doing it all right. Advice given to me by Lynn L. Augspurger in 1978, who sadly died January 2013.
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