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The best in sanitary practices?

Sunshine made an unexpected appearance yesterday afternoon, so I got my camera and went looking for . . . well, I really didn’t know. Just something. The big-leaf maples were heavy with blossoms, the bees were soaring, and it seemed like an all-around good day for photos. What I found was completely unexpected.

I started photographing a honey bee on a dandelion. Why I do this, I have no clue. I have hundreds—maybe thousands—of photos of bees on dandelions, but I was shooting even more when I saw something I’d never seen before. She pooped . . . right there on the dandelion while I watched.

I think the photos are instructive because they demonstrate how easy it is for diseases—especially those transmitted through feces like Nosema—to move from bee to bee, hive to hive, or even species to species. For some reason we don’t think of bee feces on flowers, we tend to think of it on cars, porches, bee hives, and bee suits. But as these photos demonstrate, they even leave it on flowers—in a place where the next unsuspected bee may land while she’s looking for food.

Rusty
HoneyBeeSuite

Bee on a dandelion, just hanging out.
Bee on a dandelion, just hanging out.
Suddenly, she poops in the flower.
Suddenly, she poops in the flower.
And then more.
And then more.
A sticky mess for an unsuspecting forager.
A sticky mess for an unsuspecting forager.

What is idiopathic brood disease syndrome?

A new research paper by vanEnglesdorp et al. titled “Idiopathic brood disease syndrome and queen events as precursors of colony mortality in migratory beekeeping operations in the eastern United States” is getting a lot of attention. Boiled down to its essence, it states (among other things) that colonies diagnosed with idiopathic brood disease syndrome (IBDS) have a risk of dying in the short term that is 3.2 times greater than average.

So what is IBDS? According to The New Oxford American Dictionary, idiopathic means “relating to or denoting any disease or condition that arises spontaneously or for which the cause is unknown.” We already know what brood is and we know what disease is. That leaves us with “syndrome,” which means “a group of symptoms that consistently occur together or a condition characterized by a set of associated symptoms.”

All put together, it means IBDS is a brood disease with a recognizable set of symptoms for which we don’t know the cause. It’s a fancy way of saying “we don’t know much.”

What we do know is the following:

  • In many ways, IBDS looks similar to American foulbrood, European foulbrood, or even sacbrood, but with some differences.
  • Brood of various ages appears “molten” (meaning liquified) on the bottom of the cells.
  • Parasitic mites may or may not be present.
  • According to Randy Oliver, the dead brood smells very bad but different than American foulbrood.

The syndrome is not necessarily new—it was once known under the name “parasitic mite syndrome.” The name was changed to reflect the fact that parasitic mites may not be present. At this point, it is not known whether mites transmit the disease or not. It is possible the disease is transmitted by mites but is able to persist after the mite population has been eradicated.

Rusty
HoneyBeeSuite

Why did they die?

Why is this year so different? Every day I get messages that say basically the same thing: “I just checked my hive and all the bees are dead. They have plenty of honey and lots of pollen. What did I do wrong?” Some say their bees died in a small cluster; some say their bees were completely gone. Sure, some of this happens every year, but this year seems worse.

I’m just thinking at the keyboard here, so keep in mind this is merely my opinion. But basically, I think two things are converging to kill our bees: healthy mites and unhealthy queens.

Varroa mites first landed in North American in 1987, which is just 26 years ago. It took a number of years before they spread over the entire continent, but during that time they evolved to match North American bees in North American climates. During that period the viruses they carried also evolved to fit the conditions in North America. This is not a stretch; most viruses—as well as many invertebrates—adapt very quickly to changing conditions. Evolution can happen super fast in organisms that have multiple generations per year.

However, some organisms do not evolve quickly and honey bees happen to be one of those. Geneticists have discovered that honey bees have few of the genes that allow for quick adaptation to change. Scientists believe that honey bees use hygienic or defensive behavior—rather than genetic adaptation—to respond to most external threats. In short, you have stodgy adapters being assaulted by a cadre of quick adapters.

The lethal combination of mites and viruses quickly killed off most of the feral colonies in North America, removing a critical part of the honey bee gene pool. No longer able to find sufficient wild bees, beekeepers were forced to import bees from elsewhere. As a result, most of our managed colonies have been raised from production queens that, by definition, have a limited supply of genes. Although beekeepers don’t like to believe it, most of the so-called feral colonies that are discovered today have escaped from managed hives in the recent past. As such, they are only a generation away from their production-queen origins as well.

So while the depth of the gene pool has decreased rapidly due to parasites and pathogens, the need for queens has increased sharply. It makes sense: as more and more hives die, the need for replacement grows. The irony is that the “solution” makes the problem worse.

To meet the demand for replacement colonies, queens are produced in large quantities in the south and shipped all over the country. Through no fault of the producer, these bees have marginal genetics. Why? Because there just aren’t that many genes to pick from anymore. As a result, the exhausted gene pool was spread from sea to shining sea.

And it gets worse. You and fifty other beekeepers in your county have bees with nearly identical genetics simply because everyone in your local bee club bought bees from the same producer. They all arrived in one truck, so in addition to having the same genes, they have the same diseases. It means the drones hanging out in your local drone congregation area have the same genes as well. So if you are trying to raise your own queens to overcome a shallow gene pool, the odds are stacked against you from the start. It’s one heck of a mess.

Now, back to the original question: why is it worse this year? In short, I think it has taken a number of years for Varroa mites and their viruses to adapt and spread across the country. It has also taken a number of years for most of the feral bees to die off and for production queens to replace local queens. What we are seeing now is a crescendo of bad outcomes—a perfect storm. In other words, I think it will get worse before it gets better.

Beekeepers are a creative lot, and I truly believe that many of those colonies were lost in spite of the best beekeeping practices we know. If we are lucky, we will make a discovery that saves the honey bee. But for now, we are stuck with what we have and we don’t know from where the answer will come. Or when. Or if.

Rusty
HoneyBeeSuite

Airtime for bees

Last night was great for TV bees. Quite by accident I stumbled across two pieces, one right after the other. The first, on Oregon Field Guide, was about the loss of the western bumble bee and how farmers are beginning to plant for wild pollinators to take over for the ravaged honey bee. Scott Black of the Xerces Society and an Oregon blueberry farmer are interviewed.

The second piece, on Quest, originally appeared in November 2011. “New research into disappearing bees” is about CCD, mites, and bee pathogens. Randy Oliver, Joseph DeRisi, Eric Mussen, and Michelle Flenniken chime in on these complex topics.

It’s hard to keep up with all the bee news these days so, if you haven’t seen these pieces, you’ll find them below. Each is between seven and eight minutes long.

First, from Oregon Field Guide:

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And, from, Quest:

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Rusty
HoneyBeeSuite

Avoid a honey drip free-for-all

One of the worst parts of honey extraction is the accumulation of sticky, gooey frames that remains after the process. These frames of uncapped comb, known as “wet” frames, are a storage nightmare until they are cleaned of all traces of honey.

Fortunately, honey bees are more than happy to do the job. They lick and clean every nook and cranny and put the remaining honey back in storage. This is a great system that conserves honey and makes the beekeeper’s life easier. But how you deliver wet frames to the bees is important.

It is popular to pile the frames into a great heap on the edge of the bee yard and let the bees do their thing. I have seen frames piled in wheel barrows or stacked like wood in a bonfire. This will get your frames clean in no time, but it is not good practice. In my opinion it is just plain irresponsible.

This system, very similar to open feeding of sugar syrup, has several negative consequences:

  • Open feeding draws bees from all over. Conflicts over the food source may develop into a robbing frenzy, replete with fighting and dying.
  • Shared food sources are perfect for the transmission of parasites such as mites. Even if you have worked hard to keep your mites under control, you may unwittingly bring new mite stock in from somewhere else. During a nectar dearth (a popular time for extracting) bees will travel long distances to get to your honey drips—perhaps five miles or more.
  • Honey bee pathogens, including bacteria, fungi, and viruses, can also be transmitted during open feeding. It’s sort of like eating your dinner from a community trough. You could easily bring a new disease into your apiary.
  • Open feeding also draws other insects, including wild bees, hover flies, wasps, and hornets. Some of these insects, such as wasps and hornets, may go for your bees as well as the honey.
  • Open feeding may draw other animals as well, including raccoons, opossums, and dogs into your neighborhood. If rewarded with a sweet treat, these animals may add your apiary to their regular rounds.
  • There is a real possibility that wild bees may pick up diseases or parasites from honey bees at an open feeding station. Wild bumble bees have already contracted diseases from greenhouse bumble bees, and it appears that some wild bees may have already picked up honey bee diseases such as chalkbrood. Cross-species disease transmission may be the single biggest risk to open feeding . . . and it’s just not worth it.

So what do you do with all those sticky frames? When they come out of the extractor, put them back in a super and put the supers back on the hive. Sure, there is still some risk of transferring disease, but it is much smaller than at an open feeder. And all the other problems of open feeding are basically solved.

If you are concerned about starting a robbing frenzy at your hives, there are several things you can do to reduce the chances:

  • Clean any honey drips from the outside of the supers.
  • Reduce the hive entrances to a size commensurate with the colony size.
  • Select only strong hives for cleaning supers as they are more able to defend against robbers.
  • Add the supers in the evening, near nightfall, when bees are not flying. By morning, a strong hive will have the situation pretty much under control.

With a little care, you can get your frames cleaned and still have healthy, happy bees when you are done.

Rusty
HoneyBeeSuite