The present study investigated a dominance hierarchy and its stability in a group of pigeons under a food competing situation. When a trial started, a feeder lamp was lit and one food pellet was delivered into a cone-shaped tray where a pair of pigeons (dyad) competed against each other. A pigeon that ate the food pellet was a winner of that trial. Each pair of pigeons competed in 30 trials. Thirty-five weeks after the first determination of the social ranking, it was re-determined to assess its stability. The results showed that in the first determination, except one pair of pigeons, a linear hierarchy was formed among the group of pigeons. In the second determination, the highest- and lowest-ranking subjects were the same as the first determination, however, the subjects whose social orders were moderate changed their ranking. Nevertheless, the correlation between the first and the second determination was relatively high. In conclusion, the social ranking of the group of pigeons was stable over the period of time. Moreover, the social ranking predicted by the BBS (Batchelder, Bershad, & Simpson) method highly correlated with actual dominance observations. Overall, the BBS method was a suitable procedure to identify an appropriate ranking of a group of pigeons.
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