The "prairie grouse" of North America present an interesting example of the effects of human activities on breeding distribution patterns of birds, with resulting changes in geographic distribution and spacial isolation. Thus, the Heath Hen (Tympanuchus cupido cupido) was one of the most familiar birds to the early colonists, who relied heavily on it for food. Ultimately, loss of habitat caused the Heath Hen's extinction. When the vast tall-grass prairies west of the Appalachians were settled, Greater Prairie Chickens (T. c. pinnatus) were probably more plentiful, and greatly increased as woods were cleared and grain crops supplemented native grasses. With the further advance of settlers to the more northerly and westerly portions of the prairies, the Sharp-tailed Grouse (Pedioecetes phasianellus) was encountered. Unlike the Prairie Chicken, which "followed the plow," the Sharp-tailed Grouse quickly retreated before it, and thus the Prairie Chicken soon spread over a wide range that previously had been occupied by Sharp-tailed Grouse. In some areas both species found adequate habitat for survival, and their similar niche requirements resulted in increased contact between the species. The new area of contact was probably most extensive in Nebraska, the Dakotas, and the Lake States, and later spread to the Prairie Provinces of Canada. The resulting interactions between the two species in the form of ecological overlap and degree of hybridization have yet to be fully documented, but a short review of the available information would appear to be warranted. Emphasis will be placed on the situation in Nebraska, which is probably fairly representative of the Midwest as a whole.
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