Date of this Version
Animal Behaviour 43:3 (March 1992), pp. 443–450.
Previous studies of female choice in sage grouse, Centrocercus urophasianus, have identified two processes that could drive the local clustering of male territories at leks: (1) fidelity of females to previous mating sites (“temporal spillover” hypothesis), and (2) “spatial spillover” of matings from an attractive male to his immediate neighbors (“hotshot” hypothesis). The effects of each process on male territory settlement were investigated using observations of the resettlement of vacant territories and of individual site fidelity during a 7-year field study. The frequency with which vacant territories were resettled both within and between seasons increased with mating success of the site’s previous occupant but not with the success of neighboring males. Territories vacated by the most successful males acted as foci for clusters of territories in the following year. Fidelity of males to their territories within seasons also increased with their previous mating success but was unaffected by the mating success of neighbors. However, between seasons the rate at which males returned to the lek (though not necessarily to the same territory) increased with both their own previous mating success and that of neighbors. Returning neighbors of males that failed to return were at an advantage in competing for the vacant territory. These data support the role of temporal spillover in lek formation and also suggest that territorial males use a “win-stay” rule that should favor the use of established males as cues to settlement by naive individuals. The spatial spillover hypothesis was not supported, perhaps because this process creates conflicts of interest between attractive males and kleptoparasitic neighbors that prevent the formation of stable groups.