The bees... maybe bees are just making the noise themselves? Like, you know, for sonar navigation/IFF stand-in?
It seems plausible that they would deliberately make the noise to ward off predators in the same way as their colouration. I believe they mostly use the sun, and possibly pheromones to navigate, though.
To ward off predators? Whenever I hear a bluebottle buzzing around near me my initial reaction is invariably "kill it with fire" just to get rid of the annoying noise. Although I have a low sound-tolerance so that might just be a personal thing.
According to latest research, they apparently use mostly pheromones and suchlike. Bee's, when abducted and taken several miles away from their hives, can find their way back amazingly well. One was reported to even take a train as a short cut, but that might have just been an accident coming from curiosity. Hehe, kind of like curiosity killed the cat. Would make for an odd saying at the least.
In relation to pheromones, don't keep dead bees in your house. When they die they tend to send out one of two pheromones, either one which says "dangerous here, avoid" or "rivals here, AVENGE ME!". The second one gets really annoying whenever you find a week old bee carcass on a windowsill behind the plant pot, then open the window to find a swarm of angry bees assuming that your house is a rival hive.
On the subject of insects and their aggravating buzzing;
Regarding dwarves' current dislike of certain vermin, will they eventually take measures to get rid of any vermin they see? If so, will this also have correlations with thoughts: i.e. 'Urist McEukaryota was disgusted by a horrid creature lately', but 'Urist McEukaryota is happy to have squished said disgusting vermin recently'.I, for one, would love to see some sort of dwarven Pest Control officer. Maybe just a dwarf to take over the role of cats somehow. Would be rather nasty is he also ate the vermin but...meh, stuff happens.