Mating Behavior and the Social Hierarchy in Small Flocks of White Leghorns

Abstract

Approx. 1630 treadings of domestic fowl were observed, and rank correlations were detd. between number of matings, associated behavior, and social status of given individuals. The social rank of individuals within each flock was ascertained by the usual method of noting which birds pecked which without being pecked in return. Hens of high rank in the social hierarchy usually were not courted as often by the cocks as were hens of lower social status (r= [long dash]0.68; P<0.01); they tended not to "invite" the cocks to mate as often[long dash]a tendency that was not statistically significant[long dash](r= [long dash]0.32; P<0.1), and the cocks did not tread them as often (r= [long dash]0.64; P<0.01). In 4 out of 5 flocks the hens highest in the peck order either failed to mate or to "invite" the cock to mate, or did so less frequently than most of their penmates. There was a high, positive correlation in all flocks (0.77 to 0.97) between number of matings by individual hens and the number of times they crouched near a cock as if inviting him to tread. There was no statistically significant relationship between the social rank of the cocks in their unisexual group and their sexual activities when placed singly into a flock of hens. However, when 4 cocks were introduced together into a relatively small but uncrowded pen containing hens, the dominant cock usually attacked subordinate cocks whenever the latter approached the hens. This aggression practically inhibited sexual behavior by some of the low ranking cocks. The hens also began to avoid these suppressed cocks more often. Even when tested with other flocks of hens these o" did very little mating in contrast to the dominant cock. Curiously enough, some [male][male] were tolerated and even allowed to interfere with mating by the dominant cock.