Lek Social Organization and Reproductive Success in the Greater Prairie Chicken

Abstract

Between 1964 and 1969, studies were made of Prairie Chicken reproductive behavior on a lek with a stable social organization. The social organization of this lek was altered by the removal of dominant males; three in 1970 and two in 1971. Social organization and reproductive behavior were observed on this lek prior to and following removal of the dominant males. Removal of dominant males disrupted the stable social organization on the lek. Total number of aggressive interactions between males increased following removal of dominant males. No change was noted in the total number of females visiting the lek in 1970 compared with the previous 6-year period. Likewise, no change was noted in the number of attempted copulations observed in 1970 compared with previous years. However, the number of successful copulations was drastically reduced (90% fewer) during 1970 because of increased male-male aggressive interactions on the lek. During 1971, fewer territorial males were on the lek compared to previous years, and fewer females visited the lek and fewer successful copulations were recorded than in previous years. Late nests of Prairie Chickens are less successful and contain fewer eggs compared with nests begun earlier. In some instances, the female social hierarchy may serve to delay onset of nesting, therefore reducing total reproduction for the year.