Does anyone know if varoa die when the bee dies

Well, they are flightess, obligate parasites so they won't survive long w/o honey bees to parasitize. I asked a similar question here last winter about how long mites might live off of a bee and I believe I was told that 15 days was the max.

But one thing, for sure, is that they wouldn't be going off some where to "mate and lay eggs" since that can only happen in a bees' cell where there is already a bee larva just about to be capped. At that point the foundress mite goes in just before capping and begins to lay eggs of both sexes. The males hatch first and then when their sisters hatch they mate with each of them in succession - eeeeww! - while the whole happy family sups off one wound on the developing pupa's body. (Double eeeew!)

This is why drone trapping works: foundress mites have a preference for the larger, longer-pupating drones-to-be, and it's the basis (at least as I understand it) of the MDA splitter/varroa control method which relies on a brood break and then desperate-to-lay foundress mites crowding into the first round of larva about to be capped which results in the crowding-deaths of the baby mites and the foundress-mamas when there are too many in each cell for survival. Of course, it probably also results in the deaths of the over-parasitized first brood hatch, as well.

The rapid spread across the country of Varroa destructor is entirely due to humans moving their parasitized bees around either as the part of the migratory business model or the production and sale of live bee colonies (nucs and packages). Locally it can spread from robbing bees either catching or depositing mites to a an uninfested colony, or more more rarely from mites that detach at forage points and are picked up by subsequent foragers and then flown home to the new hive.

Enj.

Well, then, I stand corrected it's not 15 days, it's 5 days, which is still 4.99 days too long for my preference.

But the comment about drones being able to enter any hive interests me a lot.

My three hives are literally stacked against each other. One hive (the middle one) is teetering on needing treatment according to the seasonal NYBeeWellness and the OTTT thresholds. It is a huge hive (3 deeps plus 3 mediums) running at full bore. In the circs., I felt my routine mite drops could overestimate the mite status due to the huge bee population (since mite drops don't count mites/bee, only the number of hapless dropees/day), so I sucked it up and did a roll. The roll numbers showed a lower but still high-side range so I'm practising watchful waiting, and doing more testing.

The other two are completely different though. One is clearly lowish 3-4 mites/day drops, and the other one often has no mites/24 hours, though usually has one, sometimes two.

If drones can move among such closely-placed hives freely why wouldn't my mite levels even out among the hives? Especially because the almost-no-mite-hive has an attractive drone club-house as its upper story. The next-to-top box (now above the feeding rim, but below the quilt box) is basically empty except for a tray of old honey comb being tidied up. During the warm months it is chock full of drones just hangin' out together. My husband dubbed this box, "the Man Cave". I was such a clueless noob last summer that for awhile I thought the "Drone Concentration Area" was something similar to what I had just cobbed together to handle the honey-mess left-over from the cut-out. I thought I was pretty clever to have "re"-invented such an established piece of bee equipment all on my own. (If you want to know how truly clueless I was, know this: for at least a week I thought I had a whole hive full of enormous fat "queens" only to discover they were actually drones. Who knew? Obviously, not me because it took me 47 weeks and 3 days to finally find all three of my "real" queens. It must have been a running joke among my bees about how easy it was to conceal them from me.)

What keeps one colony practically free of mites and the neighbor in the next apartment over under constant threat from them if the boys can bring their mites in whenever they visit? Of course, my bees are all unknown origin swarm-mutts, but still.

Enj.

If you start seeing mites on live bees in your colony, you have a huge mite population. The preferred place the mites attach themselves on the bee is on the bottom of the abdomen, on the left side, between the 2nd and 3rd segments. The mite's body is shaped so that the mite fits and the segments of the abdomen covers it, this is one reason they are so hard for the bee to remove by grooming. The other preferred area is on the thorax behind the head. In most photos this is where the mite is shown, but most of the mite photos are staged by the photographer.

There was a case in New Zealand where 200 adult bees were put into jars of alcohol for a study. They were caught by hand from the brood frames. The study needed at least 3 mites in each jar of 200 bees. The bees did not appear to have many varroa, so to get the needed 3 mites the researchers made sure they put 3 bees with a mite visible on it in each jar. The number of jars was a total of 150 for the study. Remember, they only needed 3 mites in each jar, but when they checked the jars by straining the alcohol in the lab they found 120 to 150 mites in each jar. Three visible mite became 120 in the alcohol wash. Don't rely on seeing mites to give you an idea of the mite load your colony is carrying.

It is almost impossible to kill all of the mites in a colony, so when you treat there will always be mites remaining. Even if your bees are treated before you receive them, you will still have mites. There is no location so distant from other bees that a colony will not be exposed to varroa from other colonies. Some colonies carry a mite load that would kill another colony, and they are not damaged. Other colonies have small mite loads and they die. It is the viruses the mites pass to the bees that actually kill the colony. Some bees adapt to the viruses, some don't. It is up to the beekeeper to observe and select resistant bees.

Yes, it is easy but very wasteful of bees. Last year one of my colonies that had not been treated for 3 years began dropping over 100 mites a day natural fall. It also started showing many deformed wing bees. I had the choice of not treating and perhaps allowing it to die or to treat and save it. I chose to treat. This year the colony is booming, very few deformed wing bees, and mite falls in the 30's per day. If a colony has good qualities, and some that could be improved by mating virgins from it's queen with drones from VSH queens, why let it die? I have 7 queens from a Bond Yard that have survived 8 years with no treatments, but in the last 2 years I lost 3 that may have been as good or better had I chose to treat. I now regret not removing them from the yard, but I wanted to see if bees bought from commercial stock (not the much touted feral stock we see on the forums) would last at least as long as the ones described in the French studies. Their survival was an average of over 7 years.