DOMINANCE AND PATCH DISTRIBUTION OF GREAT TITS FARUS MAJOR: A PRELIMINARY TEST OF THEORETICAL PREDICTIONS

1. Prediclions from existing models on ʹideal free distribution of unequal competitorsʹ were tested by comparing the intake rates of the birds in relation to their bowl preferences. 2. Three types of distributiuns across two patches (1 and 2, where 1 provides higher food prodLiction rate than 2) were tested: truncated (H1 > L1 > H2 > L2), semitruncated (H1 > H2 > L1 ~ L2), mixed (H1 ~ H2 > L1 ~ L2). Hi indicates highest individual inlake rate in patch i, Li indicates lowest individual intake rate in patch i. 3. The birds were studied in groups of six. They were fed by presenting two bowls containing mealworms, one howl had twice the food-input rate of the other. 4. Four birds visited the high-density bowl more often than the low-density bowl, whereas the other two birds showed no or opposite preferences. 5. The semi-truncated distribution was the only disinbution that could not be rejected by any criteria. 6. When members of the experimental group were exchanged, the changes in individual intake rates suggest that the intake rate is related to each individualʹs quantitative competitive ability rather than to the individualʹs rank.