I know Varroa mites are a nasty parasite. They vector diseases, and rob vigor from our bees.
When I first heard about them and checked for them, there they were, easy to see, there seemed to be so many, too. But, of course they had already been in my hives for more than a decade, and hadn't caused any "obvious" problems. I'm not saying they aren't a problem. I know they are. I certainly prefer that my bees didn't have to deal with them.
It's just curious to me how, so often, whenever any survivability issue, with honey bees is being discussed, it almost always comes down to how, no matter what actually did the bees in, Varroa mites are given the credit for the KILL. When, realistically, there is only one thing, and one thing only, that invariably leads to mortality, in honey bees, and all other life forms, we know of -- and that is, being alive in the first place. If honey bees weren't alive, neither Varroa mites, nor anything else would ever bother them.
Seriously, though, I almost expect to read about, how a newbee watched as an irate neighbor sprayed his hive with a bug bomb. Afterwards, the colony struggled to recover, but finally succumbed. Then, I wouldn't be surprised to hear someone suggest that they could have recovered, if they had a lower population of parasitic Varroa mites in the hive. And maybe they could have, but it wasn't the Varroa that "killed" the hive, it was the neighbors insecticide. Varroa were just a possible facilitator, weakening the struggling bees, not the direct cause.
Even when an impaired driver strikes a pedestrian, we don't usually blame the vehicle, or even whatever impaired the driver. We blame the driver, if driving while impaired was his/her choice. If Varroa didn't vector diseases, but just ate hemolymph, they might not then be the scourge that they are. But maybe they are, I'm just not so sure that they are the immediate and direct result of nearly every lost colony, for the past two decades, or so. I remember, before Varroa, when a colony ran out of stores and starved, they starved. Now, when a colony starves, I hear how the Varroa were responsible for the colony starving. That, without the interference of Varroa, that colony would likely have done just fine.
And maybe all that is true. So what were we blaming all our losses on, before we had Varroa?
Every so often, I lose a hive, usually, every late summer, early autumn, some of my smaller/weaker nucs get robbed out by the larger/stronger colonies, before I can make other arrangements for them, but not too many. I don't blame that on Varroa. Sometimes a colony loses their queen, or their virgin fails to return from a mating flight, I give them another ripe queen cell. I don't blame that on Varroa. And, rarely a colony becomes laying-worker, where I either work to get them right again, or spread them out to other colonies, giving up on saving them. I don't blame that on Varroa.
Sure, Varroa are disease vectors, and blood suckers. But are they the "driver" or just the vehicle?
Many of my nucleus colonies are taken away by customers, similarly my queens. I don't blame that on Varroa, either.