Understood,...

...but I don't share your doubts (i.e. your very reasonable skepticism) in: "...but I have my doubts that they will thrive in sizeable numbers."

From what I know first-hand about the Western Coyote, they are clever, resourceful survivors, and just as happy with mankind's cast-offs (garbage dumps) as bears, racoons, seagulls, etc., as they are with their normal prey, and most "carrion-of opportunity" (like the thriving local crows and vultures are); and I suspect the Eastern Coyote will be just as tenacious.

I believe that, rather than questioning their thriving in sizable numbers in the state, you should be anticipating a PA Game Commission bounty on them in maybe the next decade.

DTW