I live in a coastal New England town and while reading a local history I noticed frequent mention of the "partridge" as being a commonplace bird in the area. Now, however, this bird which is more specifically the ruffed grouse, Bonasa umbellus, is completely absent in our community and not to be seen at all. There are many turkeys, however. I am trying to understand what happened to them.
I read that apparently the critical ecological prerequisite for the grouse is "young stands of forest". For example, from one report: "Though grouse use all age classes of forests, they cannot do without thick stands of young forests 5 to 25 years old for cover, food, brood rearing and courting."
Our community used to be gentleman farming town and was mostly cleared for agriculture, except for a town forest, before 1950. Since that time it has evolved into quasi suburban town with a mix of conservation land, large 3 acre residential lots, and a few farms left over from the old days.
I don't quite understand how there could have been lots of grouse in the farming days, but none now. First of all, in the farming days, more or less the whole town was agricultural fields, so that hardly seems like grouse habitat. Secondly, how could grouse even exist in the pre-colonial times, because the habitat at that time would be primordial forest. When the first settlers came here in the 17th century the whole area was covered in 100 foot eastern pine trees, which were farmed for masts for the English navy.
So, should I presume that the grouse first came into the area when the farmers started cutting down all the trees, thus allowing "young stands" to arise; then the grouse population collapsed when most farming ceased in the 1950s?
If the grouse need "young stands", how do grouse even exist in areas without humans where no clear cutting occurs? I have read claims that "forest fires" clear areas naturally, but that is not the case in New England where it is too wet for forest fires to occur. For example, in Maine the ruffed grouse is abundant, but only in the "transitional zone" between unoccupied forest lands and abandoned agricultural lands where humans have cut down the trees and then left the land unoccupied. There are no "forest fires" to speak of in Maine, so the grouse apparently live only in areas modified by humans. However, this raises the question of how the grouse lived before there were farmers with axes.