The ten currently recognized species of grouse in North America have played an important role in America's history, from the famous but ill-fated heath hen, a primary source of meat for the earliest New England immigrants, to the ruffed grouse, currently one of the most abundant and soughtafter upland game birds in more than 40 states and provinces. This book summarizes the ecology, reproductive biology, and social behavior of all ten of the extant North American grouse species. It also describes the current status of grouse populations, some of which are perilously close to extinction. The social behavior of grouse is of special biological interest because among these ten species there is a complete mating system spectrum, from seasonally monogamous pair-bonding to highly promiscuous mating patterns. The latter group illustrates the strong structural and behavioral effects of sexual selection resulting from nonmonogamous mating. These influences reach a peak in the development by some grouse species of engaging in mating "leks," arena-like competitions performed by males while attempting to attract fertile females, and also provide opportunities for females to select optimum mating partners. These sexual competitions also promote strong differences evolving in sexual signaling behaviors ("displays") among closely related species. Nevertheless, a relatively high incidence of mating errors and resulting hybridization often occurs in spite of these marked behavioral differences. In addition to a text of 101,000 words, the book includes 16 range maps, 37 line drawings, and 38 photographs by the author, as well as nearly 1,400 literature citations.