Exam Notes 2: The Three Horsemen

the-four-horsemen-of-the-apocalypse-1937I am not entirely joking when I say there are Three Horsemen of the Bee Apocalypse. I think honey bee populations worldwide are balanced on a knife’s edge. Here in Canada, there appear to be no more truly feral colonies, ie. colonies that survive in the wild, without any help from a beekeeper, and which overwinter successfully. This means if managed (kept) colonies of bees fail, there will be NO honey bees in Canada. Period.

And the main reason kept colonies may fail are the Three Horsemen:

  1. Varroa destructor mites
  2. Vanishing and degraded forage opportunities
  3. Pesticides and other field sprays

Varroa destructor Mites

Varroa are alas, fiendishly successful at parasitizing honey bees. Not only do they suck the hemolymph (insect blood), of both adults and larvae, weakening the adults and damaging the pupating baby bees, Varroa vector (carry to) the bees a host of serious viruses, and our twin nemeses the foulbroods AFB and EFB. There just isn’t any good news for bees once the Varroa arrive.

Worse, they breed up much more rapidly than the honey bees and can evolve quickly, thanks to their biology and reproductive strategies, to become resistant to whatever selective pressures we place upon them. They quickly evolved resistance to the first few miticides used, and in spite of aggressive treatment programs, mite infestation is a universal experience of honey bees. We just can’t seem to get rid of them no matter what we do.

Even small mite loads have a big negative effect on the bees’ ability to generate a honey crop, or overwinter successfully. And because mites reproduce exponentially, they will, over time, completely overwhelm a colony. Brood fail to hatch, viruses (most notably Deformed Wing Virus) abound, EFB and AFB appear, and the colony collapses and dies.

There are many ways to attack the Varroa mites, from the use of “hard” chemicals in the hive, in the form of the medications fluvalinate, coumaphos, amitraz. In the form of the “soft” treatments: essential oils, formic acid, oxalic acid, hopguard, thymol. And on to the various Integrated Pest Management tricks like screened bottom boards, sacrificial drone brood, icing sugar dusts, grease patties, feed additives (like Honey B Healthy), small cell foundation (on the theory that small cells force bees to hatch faster, reducing or eliminating the reproductive power of Varroa mites), unusual hive types, and breeding up survivor stock.

So far, we can only reduce the impact of Varroa infestation. We cannot eliminate the Varroa. There is a Nobel Prize waiting for the biogengineer who can eradicate Varroa mites.

A large part of the beekeeping year is understanding when to apply mite treatments, allowing a maximum number of healthy bees to hatch out and take their place in the colony.

Principally, we treat (using whatever methods we find comfortable and effective):

  1. in early spring, to ensure the first critical rounds of brood are not infested by overwintering Varroa
  2. after the honey harvest, to ensure the critical winter bees are able to develop Varroa free
  3. in midwinter, when brood is absent or nearly absent from the hives, meaning all the Varroa are out on bees, not hidden under brood cappings, where they are very vulnerable to treatment; which at this time of year is via oxalic acid vapour or dribble.

So successful beekeeping demands that the beekeeper become expert in foiling the mites. Read all you can on the Varroa destructor.

Degraded Forage

The second challenge to honey bee survival is the increasing degradation of quantity and quality of bee forage. We are losing our wild places, we are aggressively managing our roadway verges, parks, home gardens, forests and even our farm fields. There is little tolerance for weedy, flowery pastures or empty lots, and as urban land becomes increasingly expensive, cities are densifying, which means little or no open land on which to grow anything.

Ditto in the farm fields! Now fields are ploughed and managed margin-to-margin, planted with monocultures and aggressively treated with herbicides, fungicides, pesticides and fertilizers. There is no tolerance for weeds or non-productive areas.

Because we are denying Mother Nature any place in which wildflowers can bloom in meaningful quantities, it will take a shift in our culture to make the world a better place for honey bees and all the other pollinators. We have to plant mindfully, creating pollinator pasture out of every possible nook and cranny. We have to encourage homeowners and municipalities to purpose-plant for pollinators: if every garden had one spring flowering heather, one maple tree, dandelions, a catmint plant, mints, dills or borage, sedum, asters, some clovers (so amenable to succession sowing) and Rose of Sharon (hibiscus syriacus) shrubs, there would be a season long abundance for all urban pollinators. And if we could take pride in a front yard planted in a bee pasture mix, pretty unmown grasses spangled with pollinator friendly flowers, entire cities would be pollinator paradises.

Think of all the space you see taken up with lawn grass or field grasses, replanted with an enduring bee pasture mix!

Bees are little more than flying guts. They need season long, varied pollen and nectar sources to fuel all the activities of the hive. Hungry bees, or bees forced (as pollination bees are) to eat a severely limited diet, are stunted, stressed and prone to disease and parasitization. Poor nutrition makes them vulnerable.

Poor or scarce feed also put enormous pressure on the honey bee to fly vast distances (for a bee) and in the process out-compete the many and valuable native pollinators (many of whom have short flight ranges). If we plant more forage, we help all pollinators.

The beekeeper can, if s/he is fortunate, purpose plant for their bees. Failing that, you can seek apiary locations that are favourable…acres of blackberries being one option. You can enrich your local community by “donating” bee pasture seed and bee plants to all unclaimed/idle lands, lobbying for more pollinator patches in your community.

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Pesticides and Field Sprays

All field sprays, and pesticides in particular, have effects on bees. Even sprays applied to non-bee forage crops drift onto nearby hedgerows, blanketing the wildflowers there with things that harm the bees. Field sprays can out and out kill the bees that feed upon sprayed nectar plants, or have devastating, long lasting, sublethal effects ie. deformed or weak brood, reduced drone fertility, or memory impairment in foragers, who then cannot find existing forage or their way home.

Herbicides kill all plants: check the margins of sprayed fields and you often see the blackberries or hedgerow plants killed by herbicide drift, depleting an already scarce bee forage resource.

Farmers use these sprays to reduce the labour cost of bringing a crop to market. We need to shift our agricultural practices toward the organic, coming up with innovative ways to garden and farm efficiently and organically.

The beekeeper can educate both farmers and consumers to go organic (if people don’t buy what they spray, they won’t spray it any more!!!), and plant pollinator strips in all fields, and bee pasture in all fallow fields.

Be aware that biofuel is largely corn based. Large swathes of corn monoculture are very bad for bees! The corn seed is neonicotinoid coated, causing lethal and sublethal issues in colonies near fields. And the land is being occupied by a plant of little use to bees (they will gather some corn pollen but it is not a preferred pollen due to its low nutritional profile). And the large tracts sown in corn, like the almond orchards, mean there is no season long forage within a reasonable flight range for honey bees or other pollinators, driving down their numbers and diversity. The remedy here would be requiring all biofuel fields to be organic, and to include strips of pollinator pasture.

Ditto the other killer monoculture in our world, soybeans. Soybeans are a major component of animal feed, so limiting meat consumption is also one way to help honey bees and pollinators.

 

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