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....