This has been quite a long stretch of blog silence but while we have been too distracted by other projects to write about our bees we have not been neglecting them, which is why alarming mite counts shocked us so. One week into August the hives were all below the three(3) mites per hundred bees threshold for treatment. One week into September, Beatrix and Clarissa were unsurprisingly just over with four(4) mites per hundred bees and ready for a treatment. Nae so wee Angharad was still well below threshold. But Dorcas was near ten(10) mites per hundred bees when we disheartenedly stopped counting. At this level she was a danger to the entire apiary.
We consoled ourselves with the knowledge that sudden high mite levels can happen to anyone at any time. The arrival of hitch-hiking mites is out of our control. And it is well known that mite counts rise rapidly in the fall. Bee population declines as brood rearing slows and drones are evicted but the damnable mites carry on. Interestingly this is the first time since we began monitoring mites that we have had one hive so very much more infested than its neighbors.
The evening of our unhappy discovery we applied an oxalic treatment with our Varomorus fogger. We dosed all the hives to be certain. A week later the mite count in Dorcas was half of what it had been. Effective as an oxalic fog is, it only affects the phoretic mites, the ones riding on the bees and not the ones reproducing in capped brood cells. We treated all the hives again and will do so at least twice more at weekly intervals.
We may yet save Dorcas and with more certainty will protect the rest.
The Prospect of Bees 
2020 September 18 at 16:17
I’ve seen some high counts this year as well. Last winter was so warm I had a few high counts in the spring. I like using Formic Pro in the fall as the temperatures are cooler and they can impact mites under cappings as well. That and it only takes one treatment.
I’ll be rooting for Dorcas!
2020 September 18 at 16:36
Thanks for the well-wishing.
We did not have any other treatment at hand and did not want to wait for delivery. We could, now that you mention it, have ordered some formic for the next treatment and still fogged them at once. But in the interest of varying treatments we tend to use formic and/or thymol earlier in the year and lean on oxalic in the fall.
2020 October 08 at 09:26
Been having issues over here with small hive beetles, which I’ve always attributed to varroa weakened colonies. Used checkmite for the first time and was impressed with the beetle kill–not so much impressed with the bee kill! Our warm weather and lack of broodlessness really lessens our treatment options here on the coast. đŸ˜¦ Hoping Dorcas pulls through!!
2020 October 08 at 10:36
Thanks for the well-wishing and hope your SHB issues abate.
We only had a bad outbreak one season which we addressed with homemade boric acid traps. https://theprospectofbees.wordpress.com/2012/08/08/beetles-and-baggies/ That was before we began to take varroa seriously so varroa may have been a factor.
2020 November 10 at 19:40
So I just discovered the conversations tab here on WordPress and went back and read the article. Did the beetles go into the case and die or did they go in the case and then come back out and die? I have boric acid and those little tablets.
2020 November 11 at 12:58
We do not recall much besides their numbers dropping. Borax is not an instant death poison for insects so they probably wandered in, eaten, and wandered back out to die