I agree it is not a problem to be minimized.
As for the sudden onset of this particular problem, I have no answer. I’ve lost hives to wax moth in ten days. I left on vacation and the hives were fine or so I thought. Upon my return, they were severely weakened by the wax moth. I was a new beekeeper at the time and had not taken all the available preventive steps to ward off such infestations so it was partly my fault. Still, it is sickening to lose even one hive to those critters.
With regard to CCD, or colony collapse disorder, it is my understanding that the bees leave the hive and cannot find their way back. Why this is so, I haven’t a clue. Apparently this leave the hive in a greatly weakened state and it become susceptible to the diseases I mentioned previously. I don’t know if the queen leave the hive or not in CCD.
Since I live in a city, I don’t think pesticides are too much of a problem for my bees, but out in the rural areas, it can be, even though pesticide use is down from what it was. What is used is probably more powerful.
Then, if it is a “navigation” problem (for those bees who have LEFT the hive during the day, then don’t return, then the symptom (of the ones left in the hive) is starvation, right?
drones don’t go out, the queen doesn’t go out, but the rest (almost all right?) do leave for many trips every day. Some are left to tend the eggs, feed the young in the combs, and clean/defend, but those aren’t a “fixed” caste. Or even if those are a fixed group, then they starve to death also.
How many trips do the workers make a day? 10? 50? 150?
The magnetic poles (both in intensity and location!) are shifting DRASTICALLY in the past few years: since about 1983 as a matter of fact. (Notice anything else that has changed since about 1983? Hmmmmn.)
So, what if the thresh hold of intensity is being reached: below today’s level of magnetic intensity, the bees are beginning to NOT detect their position and direction magnetically (since the poles are moving slowly from a day-day period the movement shouldn’t matter as much. North Canada or North Siberia wouldn’t matter to a bee in Texas, even if the direction were a bit off from ten years before. The bee has nothing to compare to ten years before.
But, if now 5 or 10% are at the threshhol, then 5% every 20 flights “misses” home. It dies. If every bee makes 20 flights a day x only 95% getting home each flight, then you’d kill your hive quickly.
In act, even a 99 percent chance of getting home would threaten a hive if they made 50 flights a day = 60% losses every day.
So see if the ones left are dying of starvation, or of a "disease" or toxin.
See if anybody knows exactly how much influence a magnetic field has on local (hive to flower to hive to flower ...) navigation.