This showed up on Google News this morning:
The subjects of this study are various species of South American stingless bees. Some of these do store harvestable honey, although in small quantities. It is pricy stuff. The summary of this paper is that these bees will often advertise the location of prime forage "loudly," so that competitors can "hear" (actually, this seems to have more to do with pheromone marking than sounds). The competitors know the prime forage is there, but also expect a strong presence of the claimants, and expect a fight if they go there.
By contrast, if bees communicate the forage in "whispers", eavesdroppers will likely crash the party.
I don't know how much this applies to honeybees and native bees in the US. I have noticed honeybees sharing forage with three types of bumblebees, carpenter bees, and assorted other pollinators, with little sign of conflict. Even in close proximity to our two hives, I'll typically see three bumbles for every foraging honeybee. The honeybees do concentrate on dense patches of specific flowers.
Two flower feeders I have seen run each other off: hummingbirds and hummingbird clearwing moths. The degree to which clearwings mimic hummingbirds is extraordinary. They'll chase competitors off and body-bump when necessary. I have not seen bees doing this.