the bird preying on a swarm, 9.4-84.1 %(between birds) of items in food boluses in this study may have come from swarms (diptera or hymenoptera), depending on the species (unpubl. data). The nature of swarms, being variable in both space and time, add a high degree of variability when attempting to characterize the diet preferences of a species. However our ten replicate analyses for each speciedhabitat do show consistent differences, within a single season. This suggests that there is some degree of resource partitioning related to the foraging strategies of the species.