Spacial organization among male sharp-tailed grouse on arenas

Abstract

Spacial organization among lekking sharp-tailed grouse was investigated, in the spring of 1969, near Wainwright, Alberta, by sequentially removing territorial males from the centers of two arenas and recording the responses shown by remaining territory holders. Vacancies created on each arena were filled by an adjacent male or shared by two or three birds in contiguous territories. Central vacancies were filled in an orderly and predictable manner: first by males in a central group of territories, then by males in territories surrounding die central group, and finally by peripheral males. As the number of males on arenas was reduced, the area occupied by the system of territories also shrank. Thus, territory size remained constant as did density of males on the arena. The means by which the spacial configuration of territories was attained and maintained are discussed.