[eszed]

Fun fact: queen bees can be artificially inseminated, and most commercial queens are. Beekeepers prefer naturally-inseminated queens, because they're stronger, but "nature" can't keep up with commercial demand.

You're correct about "breeding more" not being trivial, but they do it on an industrial scale. In really broad strokes: in late winter, in preparation for pollination season, they feed their hives intensively (with sugar syrup) and add extra brood boxes for the queens to fill with eggs. Then they split the hives, leaving the old queen in one box, and adding new queens to the box(es) they take off. Voila! Double (or more) the hives.

Pollination is where commercial beekeepers earn their living, by renting out hives of bees to farmers. Honey production is not necessarily an afterthought, even though it doesn't really turn a profit - it's worth doing because you'll be putting the bees on nectar flows for the summer, anyway, so you won't have to feed them, and extracting (some of) the honey covers transportation costs - but all the money's in pollination.

I could keep going and going - queen production and hive splitting are fascinating topics on their own - but I'll stop before I risk boring people with an over-long comment. I have commercial beekeepers in my family, and I've worked (summer / vacation jobs, when I was a kid) every part of the process.

(This is all in a USA-ag context. Beekeeping is - very! - different in other parts of the world.)

[chasil]

Does the pollination vastly increase the disease vector exposure, both for the contracted hive and all the insects near it?

[eszed]

It certainly does for the bees. All of the hives are in very close proximity, traveling thousands of miles on trucks, for days at a time. The bees are under a lot of stress, mites and diseases spread among them, and some hives don't make it.

Transmission to other insects? I don't know, but I kinda doubt it. Verroa mites were introduced and spread by commercial bees back in the '60s or '70s, but they're entirely endemic at this point. Some native bees are / were harmed by them, and others - based mostly on grooming behavior, actually - aren't much, or even at all, at risk. As someone above pointed out, native and honey bees mostly have different food sources, so they aren't generally in close proximity to each other. Furthermore, the bee diseases of which I'm aware are really, really specific to bees, so I doubt that, say, butterflies or ladybugs or something would be harmed by anything bees carry. I could be wrong about that, though: I'm no expert.

By far the worst threat to native insects, however, is the destruction of native plants and natural habitats. Urban encroachment and landscaping are minor factors (and please plant native plants in your yard: it's great to do), but what's harmed native plants the most has been the farming practice that comes with Roundup Ready™ and similar crops. Previously, fields grew (native) weeds, and had margins where native plants took advantage of irrigation runoff and fertilizer overspill to run wild. Now, farmers broadcast spray weed killer over everything; their genetically-modified crops are immune, but every other plant in the vicinity is destroyed.

While I'm on the subject of bees, my beekeeper uncle doesn't believe Colony Collapse Disorder is a thing. Or, rather, that it happens, but has thoroughly mundane explanations, and any kind of mystery about it has been ginned up by the media, or by beekeepers looking for compensation from the Ag Department. His explanation is that bees are fed, split, and trucked more than they ever have been. (New pesticides maybe, too, but he doesn't think they're much of a factor, since they're not sprayed during pollination times, when bees are in the fields.) All those things stress the bees, and weaken hives; weak hives (as they always have been) get taken out by wax moths and diseases.

His opinion is that old-time beekeepers haven't changed their practice, despite putting their bees under greater stress, and that young (and most amateur) beekeepers don't understand bee behavior well enough to minimize stressors or notice the signs of distressed hives. He innoculates for disease waaay more than he did forty years ago, minimizes feeding (honey is much more nutritious than sugar), and I've rolled up to bee yards ready to load the trucks, only to have him - based on his sense of the weather, and how the bees behaved when he cracked open a few hives - wave us off because the bees wouldn't cope well with moving just then. I don't know enough to evaluate his theory, but I give it credence, because his hive yields aren't any different than they have been for the last fifty years. CCD just isn't an issue for his hives.

Anyway, there's my over-long comment, and I've only got started. Bees are fascinating creatures.