I don't think there is any of the kind of habitat pheasants like in Little John, between the mature forest and the deep snows of winter, but Happy Valley has lots of cattail marsh where they can get under something and not freeze to the ground, and there is a lot of cropping going on, so they can find grains. Altmar State Forest is not far from Parish either, and has some of that edge cover common in Happy Valley.
IF they were meant to be here the pheasants would be thriving. Another exotic species introduction that fails with a change in agricultural practice, or a slight shift in climate.