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Saturday, September 24, 2016

First Fall Casualty...


Today I conducted a routine inspection of two colonies in my bee yard and the news was not good.
Less than twelve hours into the autumnal equinox and already one colony is certain to be a mite casualty. Just two short weeks ago an inspection of the hive presented a healthy population of bees and was queen-rite with two or three deep frames full of eggs and newly hatched larvae.
That was two weeks ago, but today the story was much different. I had been monitoring the hive (photo: Hive B) carefully for the last month and knew there was an issue with Varroa mites, several of which I observed clinging to adult bees, sign of a serious infestation. When I removed the lid, I should have seen a healthy, flourishing population (photo: Hive A). Instead of a mass of bees covering the frames, only a smattering remained. For nearly sixty decades bees have been a part of my life and with this mite thing, I'm at my wit's end.


In the late 1980s mites came into our Valley and changed the entire dynamics of beekeeping. Consensus has it that Varroa is now a permanent part of the beekeeping landscape, a fact of life in one's backyard apiary...certainly the case with mine. Just last week I stopped by the Beez Neez Apiary Supply to purchase containers for this year's honey crop.While waiting for Ben to fill my order, two men, father and son, came in carrying two Langstroth deep frames for inspection. The frames, one from each of two hives, had spotty pockets of capped brood, all dead. Both frames had normal honey arches with capped honey. One look at the frames and I knew mites were to blame. "There were no bees in either hive," they said. "Don't know where they went...they just disappeared." Their plight was now mine: my hive, to all appearances thriving two weeks ago, was now destined to extinction.


The frustration for us beekeepers is this late summer dwindling (as if "spring" dwindling wasn't challenge enough). Hives that survive the winter, experience the normal spring build up, and are booming during the summer months, seem to hit the wall in early to mid-August. This stands to reason when you think about it: as colony population builds, so do the Varroa...more brood for them to feast upon, which the voracious critters do until at last they overpower the hive.

(Note photo below: newly emerged adult bee with wings chewed by mites, attacked while in its incubation stage.)


This observation has led me to be diligent with mite management; you know the little varmints are and will be ever present in the beeyard and the latest literature and research suggest the beekeeper use IPM (Integrated Pest Management) to keep mites at a manageable level to ensure a colony successfully overwinters. This balance of mite vs. colony population swings in the way of the mites in mid-August, so I began treatment with the organic miticide Hop Guard (HG) the second week of August. The hive at issue not only had two treatments of HG in August but also the drone comb frame application (although with less dedication, I have to admit). When I noted the clinging mites and the drone larvae infestation, I treated the colony with a formic acid pad. All to no avail. The mites have prevailed and the colony is doomed:  I'm at a loss at what to do at this point, which will prove to be too late anyway. What is staggering to me is just how fast mites can dispatch a colony. It's like the "Zero to 60" vehicle ads. Two and a half weeks ago the second brood chamber was full of bees and at least two full frames of eggs and larvae. When I removed the lid today only a few bees were clinging to the frames and just small portion of one comb had eggs and larvae present. My guess is the decline in nurse and attendant bees caused the brood to die. "Aggravatin,' ain't it?"

Hive #2  seems in peril, also. As to the cause, I'm not certain. This colony went queenless over a month ago. An inspection showed a number of queen cells, enough to be swarm cells, although in early August swarm possibility seemed a non issue. Two of the queen cells were capless and I spotted a virgin queen milling about on one of the combs. Today I fully expected to see a nice brood pattern with brood in all stages of development. No such luck. I inspected a number of combs in both brood chambers. All I saw were the smooth, shiny bases of the cells; no sign of brood rearing whatsoever. The population seems to be holding steady, sign that mite population for the present must be at a manageable level. I decided to give the hive one last chance to raise a queen, removed a frame of eggs and larvae from another hive, and inserted it in the center of the second brood box. If the hive does raise a queen, fall weather will most likely prevent her from taking her mating flight. My prognosis is this hive will go the way of  hive #1.

The latest weapon I've added to my IPM's arsenal is oxalic acid (OA) which is applied by means of a flashpan tool inserted into the hive. A twelve volt battery powers the flash pan and in three minutes the measured dosage of OA powder vaporizes, filling the brood chambers with the fumes. The fumes coat the bees and mites with a patina of OA crystals which the bees tolerate but is lethal to the mites. OA fumigation purports to be the cutting edge of Varroa control. We'll see. However, each new trend in mite management could prove to be the panacea and sustains my hope. These days it's essential a beekeeper be an optimist.

But in the meantime the aggravation continues.... Print this post

9 comments:

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    1. Interesting you should bring up the chemical issue. The first miticides left a residual buildup in the comb and subsequent brood were contaminated by the chemical,thus proved toxic to the bees: unintended consequences again. In fact there are still traces of the chemical in foundation wax sold to beekeepers. Some have gone to plastic foundation for this reason. (No plastic yet for this beekeeper.) On the biological front, some beekeepers are raising queens from overwintered colonies, hoping to pass along mite-resistant traits to new generations. Some colonies, also, seem do more grooming of each other, removing the mites in this manner. Not sure any research yet into a predator mite that targets Varroa but numerous biologists and entomologists are working on the mite problem. Then there's the middle of the road organic approach. The miticide Hop Guard uses a derivative from the hop plant. It's a contact miticide: bee movement spreads it throughout the hive thus spreading it to the mites. I've used this for three years and believe the product is ineffective. Oxalic acid derived from wood sorrels is also an organic treatment. (Oxalis,of course, is found in rhubarb and many other edible plants.) I have done the first fumigation treatment and one colony presented over a thousand dead mites on the bottom board. That hive had been medicated with HG twice and had one heavy dusting with powered sugar (makes the bees slippery and mites fall through the screened bottom boards to their deaths). Varroa mites are here to stay. The beekeeper can only hope to assist his colonies keep them at a manageable level. Good to hear from those Beebes. TMJ

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  2. As if keeping bees didn't already have its challenges. I'm curious to find out about the colony on the Frohning Farm. Keep me posted. (I'd type more, but I have a stiff finger). Buzz buzz!

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    1. Beekeeping has always had its "challenges," but these were minor irritations (swarm abatement, brood diseases, laying workers, pesticide kills, bee dysentery [nosema], etc.). Mites are an entirely different level of frustration as there seems to be no effective way to combat them. In the meantime the colonies die and we replace them every spring. Thanks for reading, kiddo. TMJ

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  3. Wow that is crazy! And after treating with Hop Guard in August? Did you get much mite drop from that treatment? I plan on doing another oxalic treatment in winter to be safe. Even with 3 treatments, I'm sure there's still a lot of little buggers in the caps that are able avoid the treatments.

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  4. Yeah, no wonder the bees can't make it past fall each year. I was astounded by that mite load. I checked the tray the day after the photo and the drop appeared to be only a couple dozen. Yes, I treated that hive with HG in August and also did one heavy dosing of powdered sugar. I didn't have trays to check on mite drop during the HG treatments so have no idea how effective they were. Hope to do another OA treatment before the end of the week. I'm planning on bringing the Frohning hive back to the property before the wkend also and will treat it as well. Should be interesting to see what's going on mite-wise in that hive. Thanks for the comment. TMJ

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  5. My neighbor, Ben, yes, Ben from Beez Neez (sp?) is a bee keeper. His hive is in the corner of his backyard, which border mine. In the late summer I kept noticing dead bees on my cement patio in the mornings. I eventually figured out that every night a select few would swarm around the light instead of returning to their hive. After more research I learned there is some strange phenomenon where they can become entranced by the light, almost hypnotized, and will die while in this state. I felt terrible. I started leaving the light off until complete darkness. Still didn't work. Such a strange phenomenon. Great to see you blogging again, Mr. J.

    - Carrie (Whitney) Milburn, a.k.a. "Muffy". I think you were my teacher right about about 30 years ago. ;)

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    1. That's right neighborly of you, Muffy, killing off your neighbor's bees. So much for "Save the Pollinators,"right? What a coincidence main minion Ben is your neighbor. He's almost single handedly running the Beez Neez these days. I just hope the BN can stay in business.

      I doubt you did much damage to Ben's bees. Summertime colonies are at their peak population and a dozen or two here or there won't do much harm. I have set up a moth sheet in our backyard at night to see what moths lurk out there in the Valley and the sheet attracts a half dozen or so honeybees every night. Most insects are "like moths to the flame" and honeybees are no exception.

      Say it it ain't so: thirty years ago? Seems like just yesterday I was asking you to stand and deliver your memory work. You have always been my Muffy #1 and I've yet to find a Muffy #2. Good to hear from you, Ms. Muffy. Thanks for reading The Ripple and the ramblings of this old man. TMJ

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