Thursday, April 30, 2015

Making Space

(Note: Meant to post this yesterday, but forgot. Oh, the distractions of motherhood!)

Due to some out of town travel, I had to postpone shipment of my packages from April 15 to April 30. In preparation for that, I did a quick check on Austeja on Sunday to see if/what I could pull from it for the packages. At the same time, I made a bit more space for her by adding some empty bars at the front of the hive and after the drone comb. Post-inspection, the comb was arranged a bit like this:
End entrance is to the left of this diagram.
Diagram is not to scale. The brood nest is much wider than it would appear.

I figured that would give them enough space for another week. That's why I was so surprised to open the observation window this morning and see quite a few queen cups (maybe 6-10) on the side of a couple combs. It's always hard to know if the queen cups are just for practice or if they're a sign of getting ready to swarm. However, just in case, I performed a quick inspection this morning.

A couple of queen cups
I didn't see any eggs or larvae in the queen cups, but I'll admit that it's sometimes difficult for my middle-aged eyes to spot them when they're super tiny. All the previously empty bars up to the capped honey were built out already, and the bees were were making more drone comb. Also, it appears that the third bar from the entrance was being filled with honey. I haven't decided if they're backfilling or just backward, but I'm not taking chances. It's always amazing to me, though, just how much work the bees can do in 3 days if they have resources.

Mostly drone comb with some worker brood to the right.

I added a couple more empty bars before and after the brood nest. I also opened the brood nest with a couple of empty bars between bars brood. Hopefully, I've done this in time to suppress swarming. The forecast is predicting that we're going to skip right over spring and rush into summer with temps in the 80's next week, so that helps ease concerns about the brood chilling.

Dandelions are starting to open now. Magnolia in full bloom.

As it turns out, I received a call on Monday to say that due to weather issues in the south, my shipment has been delayed until May 6. I'll be checking the observation window daily over the next few days for any sign that the bees are frosting those queen cups. However, if they do get capped, I suppose that could work out to my favor, too. I've been planning to requeen the packages in June or July. However, if I end up with swarm cells, I could install them with the packages at the outset and wouldn't need to bother ordering any queens. Hey, that gives me an idea...

Tuesday, April 21, 2015

Double-Walled Insulated Horizontal Hives with Extra Deep Frames

5/10 - Corrected spelling of "Liedlich." Sharashkin's wife is the artist, not Lazutin's wife. Added additional details about European bees, timing of honey harvest, and insulation as provided by David Liedlich.

For a long time now, I've been curious about the traditional hives horizontal hives used in Eastern Europe, but I haven't really found much info on them. Most likely, that's my fault since I haven't done much looking. However, I hit a jackpot at my last local beekeeping meeting when a fellow club member, David Liedlich, gave a talk on his newest experiment -- the Russian long hive!

This is going to be an unusual post in that it's going to present the highlights from a talk that featured the highlights of a different talk, but it's all good, right?

For Christmas 2013, David Liedlich mentioned that he gave his wife a copy of the book Keeping Bees with a Smile by Fedor Lazutin. The book, as you may have guessed from the author's name, is by a Russian beekeeper who uses traditional horizontal Russian hives. Originally published in Russian in 2009, it was translated into English in 2013. After reading the book, Liedlich and his wife became fascinated by Lazutin's ideas and traveled to the Ozarks to hear him give a presentation last fall. (Note: Although Lazutin speaks some English, the talk was in Russian, and translated by his editor, Leo Sharashkin.) The presentation Liedlich gave to our club is based on the talk he heard last year.

Traditional Russian hive. Sharashkin's wife is an artist and decorates his hives.

About Fedor Lazutin
Sadly, Lazutin passed away this past February from a brain tumor. However, prior to that, he and his wife, Lena, kept approximately 100 hives in the Kaluga region of Russia (approximately 150 miles outside of Moscow.) The conditions in this region are quite similar in terms of temperature and forage time to Zone 4 in the US (e.g., New Hampshire and Vermont).

Red shows the Kaluga region.

Fedor began his beekeeping career with Caucasian bees in Dadant hives. However, he suffered so many losses that he decided there had to be a better way. As a result, he began researching historical beekeeping to see how things were done in the past. This led him to beekeeping in traditional Russian hives.

He says that he never uses any kind of treatments for diseases or pests. Rather, he relies on good forage away from farms that use pesticides, not feeding, and vigorous bees as well as his extra-deep hives for success.

The Bees
Lazutin's book describes how, prior to the Soviet era, Russian beekeepers used European black bees. The European black bee is the native bee of much of northern Europe (England, Ireland, France, Poland, Germany, Russia, etc.). Over the years, it has been replaced by the huge infusion of southern races of bees. Places with wild European dark bees are much more rare these days. When we think of Russian bees, we primarily imagine the "Russian" bee from the Primorsky region, which is likely derived from Carniolan bees that were imported there long ago. The "Russian" bee from Primorsky is not a black bee or even a separate race of bee. It is simply a European bee that has been exposed to Varroa mites for much longer.

In any case, the black bees were known for being highly defensive, so when beekeeping became a government-regulated activity, gentle grey Caucasian bees were shipped to apiaries all over Russia. In fact, this is the bee that Lazutin started with as well. However, over time, Lazutin began to feel that the Caucasian bee is not as well adapted to the colder climates and shorter foraging seasons outside of the Caucasus. As a result, he switched to the native European black bee.

Lazutin's spring starts around March, and his bees can build up from a population low of about 15,000 in spring to about 80,000 during the peak of his summer in late June/early July. The colony's peak population corresponds with the maximum bloom for his area.

According to Lazutin, beekeepers should maintain and improve their local strains of bees. If one can't obtain local stock, then he says beeks should improve what stock they have by installing swarms.

Historical Perspective on Hives
Observing hives in their natural environment can provide beekeepers with insight. However, local conditions should also be factored into the observations. For example, we know that bees live in hollows. However, the further south one goes (i.e., the warmer the climate), the less important a hollow is to the bees. For example, bees like Apis dorsata and Apis cerana make their nests directly on tree branches.

In the 19th century, books started making recommendations for hive size based on observation of feral hives. Hollows with a 10" diameter were recommended. However, Lazutin purports that this conclusion was faulty. Observations were skewed by logging activities that had destroyed trees with larger hollows. In other words, bees were simply making the best of what was available. According to Lazutin, modern beekeepers are continuing to use hives that are too small based on erroneous centuries-old conclusions.

Horizontal hives vs. Vertical hives
It's rare to find live tree hives, log hives, gum hives, or skeps anymore. For reasons related to convenience and practicality, these have been replaced by moveable frame hives. Commercial beekeepers that need to move hives around frequently will certainly want vertical hives. Horizontal hives with extra deep frames are extremely difficult, if not nearly impossible, to move, so they are well-suited for hobbyists and stationary apiaries.

A horizontal hive with 25 extra deep frames (each frame is the size of 2 Lang deeps) has the equivalent volume of 5 Lang deeps. The enormous volume of this hive reduces swarming and provides enough space to store all of the honey produced in a single season.

Horizontal hives with deep frames in various cultures
Horizontal hives are not a new invention. Records of them go back to the 1500's, though they were comprised of bars on tubs. In the 1800's, Georges de Layens designed a popular deep horizontal hive with movable frames. Variations of this design have been used in a number of European countries, including:
  • Spain's colmena Layens hive
  • France's ruche de Layens
  • Trough hives in Sweden (tragupka) and Denmark (trugstade) (Note: traditional Danish hives are available for purchase from Swienty.)
  • Poland
  • Ukraine (Note: the Ukrainian hive is taller than wide. It holds 36 frames in 2 18-frame rows. Although it winters well and can be used with standard extractors, Lazutin says that it tends to encourage more swarms.
Constructing a horizontal hive with extra deep frames
Lazutin recommends building the hive with double walls. For the inner lining, he says solid wood is best, though plywood is adequate. An interesting sidenote is that L.L. Langstroth also recommended double-walled hives to provide insulation, but he correctly predicted that "Such is the passion of the American people for cheapness in the first cost of an article, even at the evident expense of dearness in the end, that many, I doubt not, will continue to lodge their bees in thin hives in spite of their conviction of the folly of doing..."

A layer of insulation should go between the inner and outer walls. Lazutin recommends 1 1/2" to 2" of foam polystyrene. He says 2" is equivalent to 5"-6" of wood. However one could also use natural materials like flax fiber mats.

The entrance, which is positioned about 14"-16" down from the tops of the frames, should be 1/2" high to allow bees to come and go without getting blocking the entrance. The entrance is nearly the entire length of the hive, but it can be reduced to whatever length is needed at the time. 

A division board is used much like in a KTBH. However, rather than fitting snugly against the sides of the hive, Lazutin recommends that there be a gap at the bottom of the division board. This allows bees to travel the entire length of the hive and see how much available space they have.

One can use a flat roof, but Lazutin recommends an insulated peaked roof, particularly for snowy climates and a steel hive stand about 16" high.

The hive uses extra deep frames that sit tightly together just like in a TBH. The frames are equal in depth to 2 Lang deeps. The frames can be built as a single frame (though it's difficult & expensive to find an extractor that will accept the frames), or two deep frames can be bracketed together. Note, if using commercially available frames, which have a bit of space between them, a burlap cloth should be laid over the frames to close them off. A bit of extra space is left beneath the frames. Unlike with a TBH, Lazutin recommends using foundation, though he makes his own from treatment-free wax. However, he also recommends that the foundation size match the size that is natural for one's particular strain of bee.

Liedlich modified some standard Lang frames to sit side by side and make a "ceiling" for the bees.
Interior view of Liedlich's hive. Instead of using large frames, he's bracketed two Langs together.
Note: the bottom of the hive has not yet been added.
Clustering in the hive
In his book, Lazutin discusses how a cluster moves upward at a pace of approximately 1 mm every 24 hours during the winter. After doing a bit of math, he concludes that the cluster needs a certain amount of space overhead in the frame so that it can move unhindered to new honey. (I can't recall exactly, but I think it translates to a minimum of 16" tall frames for his climate For other climates, the required number of inches will vary. For example, in France, where the Dadant hive was developed for a much shorter, warmer winter, 12" is just enough, though it's pushing it, too.)

Page from the book comparing clusters in various hive designs

Harvesting honey
Just as with a TBH, honey is harvested from the edges of the hive. One interesting note is that Lazutin recommends harvesting just once per year, about 3 weeks after the last brood has emerged in the fall. He says this makes harvesting easier because they are not as defensive. Also, the brood must must be out of their cells so that they can rearrange their stores as they see fit. Of course, not all honeys have the same nutritional/medicinal value to the bees. By taking only surplus honey from the edges of the nest after the stores have been rearranged, beekeepers ensure that they are leaving the bees what they need to stay healthy through winter.

Advantages of a horizontal hive with extra deep frames
For all you TBH beeks, these advantages are going to sound really familiar, but I'll list them anyway.

  • Minimal interference with the brood nest since it doesn't get exposed during inspections. The brood nest is inspected and disturbed once in the spring in a Lazutin hive. The rest of the management through the year need not disturb the brood nest.
  • Easy inspections since the brood nest remains largely undisturbed
  • Easy to expand/decrease the hive size without disrupting the brood nest's microclimate. This is in stark contrast to vertical hives, especially in cold climates where adding supers too early can chill brood or removing supers can cause swarming if done too late.
  • Lazutin is very much against feeding sugar, so the colony prepares for winter on it's own. It also overwinters without any human assistance.
  • Honey is harvested at a time when the bees are beginning to cluster, so they are not as defensive.
  • The colony can winter outdoors instead of in sheds, which is common in Lazutin's climate.
  • Easy to strengthen weak colonies by combining them with stronger ones. The long entrance allows beeks to create entrances where needed.
  • The long entrance also allows for making easy splits.
  • No heavy lifting of supers or brood chambers. (Note: 1 extra deep frame of honey can weigh up to 20 pounds.)
  • Bees consume less honey in winter in an insulated hive because they aren't working as hard to stay warm.
Disadvantages of a horizontal hive with extra deep frames
  • One has to either modify an extractor to take the extra deep frames. Or if one is using two frames bracketed together, they have to be separated before inserting them into an extractor.
  • Difficult to move the hive. Virtually impossible to move in the summer when full of honey. Even an empty hive requires more than one person to move it.
Tweaking the hive
  • Since writing his book, Lazutin has stopped making a raised screened-off chamber under the frames.
  • He also doesn't leave screened bottoms open during the winter because the bees were using more honey.
Lazutin's Observations
When inspecting, Lazutin insists that disturbances be kept at a minimum. Beeks should look for brood and not queens. He believes that constant disturbances lead to more swarming. He also says his hives rarely swarm. He credits this to the hive's large volume and to his practice of removing surplus honey and old comb from the brood nest. His queens stay productive 2-3 years, and he actually has to induce swarming. 

He hives primary and secondary swarms individually, but weak afterswarms are combined. Feeding weak swarms seems to be his one exception when it comes to feeding. Initially, he didn't feed them either, but in the end, he relented. He felt that he was losing a lot of perfectly good bees who would have survived and done well if they'd had just a little boost in the beginning.

He's also had good results by combining weak swarms with weak, older colonies. If he has a shortage of swarms, he'll also fix a weak colony with queen cells from a colony preparing to swarm. 

Wintering and moisture control
Lazutin recommends a couple of options for wintering. One method uses a special frame containing 10 lbs of silica gel dessicant placed behind the divider. No top vents are used.

Liedlich plans to experiment with a 5" thick peat moss pillow on top of the frames under vents -- very much like a super filled with wood shavings above a Langstroth hive in winter (or like the quilt in a Warre). He indicates that he is trying to mimic an approach that is used in the attics of houses -- vents in the attic with insulation on the attic floor. 

More Info
I took a number of notes on Lazutin's beekeeping year. However, I'll never finish this post if I don't stop somewhere. Maybe, if I get enough interest in the comments, I'll write up a Part 2. In any case, I highly recommend reading his book, which has detailed notes on his yearly maintenance activities. If you're unsure whether you want it, you can check out the contents of the book and see some sample pages online. One last thing I wanted to mention -- you can get plans for a Russian horizontal hive on Sharashkin's site, Horizontal Hives. The plans have lots of measurements and photos, so they look pretty easy to follow.

If you happen to speak Russian, Lazutin also has a number of talks on YouTube. I minored in Russian and even lived in Moscow for about 6 months, but I've forgotten way too much. This may give me the motivation to brush up on old skills so that I can listen in. :-)

Sunday, April 19, 2015

Drone Comb & Wax

Austeja was not a particularly strong hive going into winter, and although it made it through, it's pretty small still. That's why I was surprised today to see it starting to make swarm preparations. I guess it feels good because it has a lot of capped stores left over from winter, and it had already drawn the empty bars I'd inserted last week. It also had a nearly full bar of pollen and a bar of drone comb. The other bars were full of capped worker brood. No queen cups yet, though.

I decided to add an empty bar to both ends of the brood nest. I also opened the brood nest with a couple of empty bars. Hopefully, that will suppress their urge to swarm, but I'll definitely check them again soon.

Plenty of things are starting to bloom now, though. Crocuses are still available, though I think the swamp cabbage bloom is about over since I can see their green leaves from the road. However, bulbs like squill and daffodils are in full bloom now (not that the bees like the daffodils much). Magnolia and forsythia are starting to bloom, too, so I'll need to be diligent about making sure the brood nest stays open.

There were way too many combs left from my dead-outs to store in the freezer, so I moved them all to the nucs. My thinking was to install the packages that are coming in the full-size hives, and I'd rather let Austeja rob the nucs than train her to rob the other hives. Today, I noticed that there weren't any more robbers coming and going, which was a good indication that the honey was gone.

I won't go into all the details of why, but I now have two sizes of bars -- 18 1/2" and 20". Unfortunately, the sides of the observation hive have bowed outward, which means that the smaller bars are really hard to fit into that hive. They keep wanting to fall inside. As a result, I've made the decision to phase the short bars out. As Austeja empties out the old honey or fills them with brood, I'm moving the shorter bars to the back of the hive so they can be filled with honey and harvested.

I'm tired of messing with these short bars, though, so my younger son and I harvested the wax from the short bars in the nucs today. We kept the wax on the longer bars for the packages, though.

My packages were originally scheduled to ship April 15, but due to some unexpected complications, I postponed shipment until the 30th. Things are getting very exciting around here very quickly. 

Sunday, April 12, 2015

A Different Approach to Overwintering Honey Bee Colonies in NorthernClimates

At our local beekeeping club meeting, Alex Papp presented his approach to overwintering bees. I feel like I should preface this post by saying that from a personal perspective, I disagree with much of what he said, and I'm not going to repeat it. I don't think he's wrong or bad. Actually, I think he has a very kind heart for his bees and is doing what he feels is best. We just have widely different perspectives. By his own admission, he views his bees as pets, and I want mine to remain wild creatures. He believes in a regimented approach that is strictly timed to the calendar. I believe in watching nature and taking cues from what I see happening. He treats and feeds on a schedule whether the bees need it or not. I don't. He said his primary focus is honey. Mine is not. However, he shared a unique and novel way to keep his hives warm over the winter. As we come out of a grueling winter, that seems to be the thing on everyone's mind, so I thought I'd share.

Alex's method is really meant to be used in a Langstroth hive. Basically, his setup uses the following components:

  • Screened bottom board with a solid bottom.  The screened bottom board has a removable tray that can be greased and used for varroa counts. It's deeper than a normal screened bottom board so that it can accommodate a lightbulb in winter. The back of the screened board has a door in back that uses a screened cover in summer and a solid one in winter. The solid door is notched so that the cord for the bulb can slip through. The dimensions of the waterproofed solid bottom are bigger than the hive so that a foam insulator can fit on top, but more about that in a minute.
  • Lightbulb. During the winter, Alex inserts a 25-watt lightbulb with a ceramic socket into the tray for the screened bottom. He says one could also use a 15- or 40-watt bulb depending on factors like wind or temperatures, but 25 watts work for him.) The lightbulb and socket are attached to a piece of metal that is sort of C-shaped. He puts it into the hive lightbulb down. This way the bulb doesn't get dirty with cappings and whatnot that fall. Also, he covers the metal with aluminum foil for easy spring cleanup. Additionally, the metal radiates heat from the bulb. The lightbulb is painted red because bees don't see red. He turns the light on whenever temperatures drop below 40 degrees F. 
  • Entrance and 2 Deep Brood Boxes. These go on the bottom just like normal. The entrance is reduced to 2".
  • 1 1/2" shim. The shim provides space for 5 large fondant patties/pollen patties.
  • Homosote board with 2" hole in the center. The homosote board absorbs moisture. The hole provides ventilation.
  • Screened board. This enables him to look down the hole to check on the patties and bees. He says that he checks his bees in in -10F weather.
  • Newspaper. A layer of newspaper covers the center of the screen, but he leaves 1" uncovered around the corners of the screen.
  • Homosote board. Another homosote board goes on top.
  • Foam insulation. A box made of foam insulation goes all around the hive. It sits on top of the solid bottom board so that it never touches the ground. It has two holes that allow for ventilation. The bottom hole is near the entrance so that bees can come and go. Alex also uses this hole to check the lightbulb (in case it needs to be changed). The top hole sits just below the top of the hive. Sometime he uses a square plug made of foam. The square does not completely fill the circle, so it slows down warm air loss rather than stopping it completely.
  • Board and Plastic. The whole thing is topped by a board and a plastic sheet. The board keeps it from flying away, and the plastic keeps everything dry.
Screened and solid bottom. You can see how the solid bottom is larger.

Foam insulator. You can see the plug in the top hole.

He claims that his bees never cluster during the winter. As a result, they never slow down, and the queen doesn't stop laying. By the time spring arrives, he has a massive population. When the black locust blooms in May, his hives are bringing in 30 lbs of honey per week. He harvests 3 times per year, and he gets about 120 lbs per hive.

He says that by keeping their bees alive, northern beeks take the pressure off the package industry to produce low quality bees. Additionally, it reduces the importation of pests that travel with packages.

He provided a lot of other info on his feeding and treatment practices, but I'm going to skip that. 

I was told that Al Avitable did a write-up of this approach for the January issue of The American Bee Journal, so if you subscribe, you could read that article. 

I'm not sure that I would ever use this approach. However, I'm always impressed by the creative problem-solving skills demonstrated by beekeepers in the face of adversity.

Saturday, April 11, 2015

A Photographic Journey to Experience Beekeeping Abroad

Renee Ricciardi gave a delightful presentation at my local bee club today. She is a Boston-based beekeeper and a photographer. She was also the recipient of the 2013 Morton Godine Travel Fellowship. Her project involved traveling 6 months (over the course of 2 years) and photographing bees, beekeepers, and apiaries all over Italy.

Her presentation was primarily a showing of photos and talking about each one. It's difficult to capture the things she said because they require the context of the photos. However, I particularly liked her stories related to Il Pungiglione -- The Big Sting. Basically, The Big Sting is a social cooperative that takes in people who are either serving prison sentences or who are on parole and teaches them to keep bees. Most of these people have offenses related to drugs, alcohol, and prostitution, and they find that beekeeping is a wonderful tool to heal these people and help them grow skills and behaviors they will need to function successfully in the real world.

Another favorite story was about how one of the inmates in Il Pungiglione showed her how to blow smoke rings with a hive smoker. I wish the photo was available for viewing online. I was really impressed!

Her stories about beekeeping in Italy were so interesting, especially the ones pointing out differences in beekeeping practices. One of these differences has to do with how they take notes -- they write directly on the hive. Another interesting difference is how they go about trapping wasps. Over there, wasps are a huge problem. To get rid of them, beeks cover boards or even cardboard with sticky glue used for trapping rats. Then they place pieces of fresh prosciutto, which is such a delicacy, on the board to attract these carnivorous pests. As wasps come to feast, they're trapped in the glue.

Renee conscientiously pointed out that her project is an art project and not a documentary. At least one photo was carefully compose and directed. One of the reasons she was inspired to do this project was Italy's temporary (2-year) ban on the use of neonics in corn. She goal was not to point out how bees are dying, but rather something idealistic about bees and beekeeping, to show how bees and people can live together.

You can view some of her photos (she showed us way many more) on her website. She also has Twitter, Instagram, and FaceBook accounts that your can follow. I neglected to get the account names, but you can look them up if you search for her name.

Friday, April 10, 2015

Post-Mortem & Spring Managment

Sorry for the lack of photos in this post. I forgot to take a camera/phone when I went out to the hives last Thursday.

Temps were in the sunny, calm 60's that day, so it seemed like a good time to dig in and see what was going on. Looking through the three dead hives, there was black mildew on the walls and follower board -- a definite sign of moisture. The bees looked wet and slick, too, another sign that condensation had killed most of them.

A number of bees were also buried head first in the cells like they had starved. I'm thinking that condensation probably killed most of them, and there weren't enough bees remaining to stay warm enough to move to new honey.

There was also a some poop in the hives. Not crazy poo like I'd expect with nosema, but a little bit. I did some research on the subject and found that contrary to popular opinion, bees will go #2 in the hive during extended cold weather. According to Dr. Milbraith, extended cold weather in combination with a digestive issue will cause dysentery.

Nosema can be diagnosed/ruled out only via lab test, but instinct tells me that this was a digestive issue. There wasn't any poo on the outside of the hives and very little inside. However, I believe I made a mistake last fall. It was starting to get chilly last November when I closed up my hives. I figured it would get too cold for syrup, soon, so I put straight up sugar in the hives. But it didn't get really cold -- not until January. Meanwhile, they were filling up their little guts with difficult-to-digest sugar. Then the relentless cold hit cold didn't allow them to evacuate for months on end. I didn't really realize until recently that straight up sugar should only given during the early spring when it's too cold for syrup, but warm enough for cleansing flights.

Another interesting thing I noticed is that Peach, the colony that I felt was the strongest had a supercedure cell. It wasn't capped, but it did have a frozen larval occupant.

I know the colonies went into winter on the small side, but none of them (including the one that survived) went through more than 3 bars. I guess I shouldn't have worried so much about feeding them last year. They had collected more than enough honey on their own.

I ended up dumping out the bees that were lying on the hive floor. The new packages will have to clean out bees in comb. I also consolidated the combs from the dead hives into two hives. My freezer is stuffed to the gills, so I left the comb outside. If they get robbed, they get robbed (and I have seen robbers). In the event that they aren't looted, I may scrape the caps off and give them to the new bees.

Finally, after dealing with the dead hives, I followed the diagrams in Les Crowder's book and reversed the comb in Austeja. (Full bars of stores go next to the end entrance followed by brood nest and empty bars.) I don't know if I used the right timing. His book just says to do it in spring. Well, I saw bees bringing in pollen (actually, they look like little yellow ghosts from swamp cabbage pollen), so I figured it would be ok.

As I pulled the comb out, I didn't look for the queen, but I also didn't see any brood. Carniolan/Russians are known for not laying much until the nectar flow starts, but I hadn't expected to see nothing either.

Next Tuesday is supposed to be in (gasp!) 70's, so I'll take another look at it then. Fingers crossed.

Wednesday, April 8, 2015

What stimulates swarming, and what does it mean for keeping your bees? Another Talk by Dr. David Gilley

I apologize that I've put off sharing my notes on Dr. David Gilley's second lecture at my last beekeeping club meeting. (You can check out my notes on his first lecture, which was about pheromones and waggle-dancing, if you like.) The truth is that I started this post ages ago, but then Blogger glitched, and I lost everything I'd written. Then I got so distracted by getting my tax stuff together and whatnot. Things are back on track, though, so I figured I'd give this one more try, especially since Dr. Gilley, who is a behavioral scientist at William Paterson University gave such an interesting talk on a subject that concerns us all this time of year -- SWARMING!

Without further ado, here are my notes.

Review of Swarming as Part of Reproduction

Four Stages of Reproductive Fission in the Honey Bee Colony

Stage 1: Preparation for Fission
  • Queen rearing. Queens are reared so that the remaining colony (and/or any after-swarms) will have a queen.
  • Worker population increases. The worker population increases. There need to be enough workers for both the swarm and the remaining colony.
  • Nectar hoarding commences to ensure a ready supply of resources for the new queen and her colony.
  • Physiological changes in mother queen. The mother queen undergoes physiological changes such as slimming down so that she can fly with the swarm and vision changes so that her eyes get a workout
Stage 2: Swarming
  • Nest departure. Just before the new queens are capped, the mother queen and a large portion of the colony depart from the nest and fly off. They become the daughter colony.
  • Bivouac clustering. The swarm has no home, so they cluster somewhere until scouts can find an acceptable new home for the swarm.
Stage 3. Daughter Colony Established
  • Scouting. Scouts are dispatched from the swarm to find a home for the new swarm. 
  • Decision-making. Scouts report their findings to the swarm. Collectively, the bees decide which home they want.
  • Bivouac departure. Once the swarm has made a decision, they depart en masse to their new home, and set up shop their.
Stage 4. Parent Colony Reconstituted
  • Queen Elimination. The first virgin queen to emerge kills the other queens in their queen cells to eliminate competition.
  • (Secondary Swarming). If the colony is very large, secondary swarming may occur. In this step, additional swarms may be cast. Virgin queens will fly with them. Secondary swarms help speed up queen elimination.
  •  Queen mating. Once she has eliminated her rivals, the virgin queen will take a series of mating flights and begin laying eggs.

Proximate Causes of Swarming

  • In order to better understand why bees swarm, we need to identify proximate and ultimate causes of swarming.
  • Proximate causation is a mechanistic kind of causation. It is the event that is immediately responsible for causing something to happen. Ultimate causation is an evolutionary question that addresses fitness adaptive arguments.
  • Example: Male stickleback fish have very red bellies. The male stickleback is also highly territorial and will attack all other males entering his territory. Why does the male attack? There are both proximal and ultimate causes for this aggression.

    Proximal cause:
     A male sees the red belly of an intruding male and attacks. The red belly of the intruding male is a sign stimulus that causes releases aggression in the male defending its territory.

    Ultimate cause:
     By chasing away intruding males, a male decreases the chances that eggs laid in his nesting territory will be fertilized by another male.
  • With regard to bees and swarming, beekeepers need to be able to identify Stage 1, the preparation for reproductive fission if they want to prevent swarming. The ultimate causes associated with the events of this stage are pretty obvious. If beekeepers want to get ahead of the game, they need to understand the proximal causes associated with the events of preparing for reproductive fission.
Ultimate causes for Stage 1 of Reproductive Fission

Seasonal Physiological Changes

  • During the spring, many animals experience seasonal physiological changes as a result of changes in day length and temperature. These environmental cues (in the form of longer dyas and warmer temperatures) cause gene expression changes in neurosecretory cells of the brain. These changes cause hormonal changes in the production of various hormones, which leads to physiologic changes. For example, as days grow longer in spring, the physiognomy of male birds changes as their testes begin to grown and produce more sperm. These physiologic changes lead to behavioral changes. Again taking the example of birds, in spring, they start defending their territory, attracting mates, and building nests. Nest building and egg laying are the end result in a chain reaction of events that began with a change in day length. If you wanted to prevent birds from reproducing, you could simply manipulate the amount of light they receive.
  • The advent of spring also causes seasonal physiological changes in bee colonies. The image below shows this sequence cues and events. 

In the chart above, 7 hypotheses have been identified as proximal causes for swarming. Note that these causes are not exclusive (i.e., rather than being stand-alone causes, they likely work in tandem to cause swarming). These proximal causes are: 
  1. Photoperiod (longer days)
  2. Warmer temperatures
  3. Nectar availability
  4. Increased worker density as a result of more eggs having been laid over time
  5. Increased comb congestion due to increased worker density
  6. A younger population as a result of increased egg laying
  7. Decreased queen pheromone distribution. As the population gets larger, the queen is not able to disperse her pheromone as effectively.

Review of Literature

The evidence for causal links between colony-level cues and swarm preparation has been summarized by Grozinger et al. (2014) in a review of literature. The review indicated that a number of cues can be correlated with swarming events. However, no one single cue causes swarming. Highlights of this review are as follows:

Increased Worker Density

  • Colonies began constructing queen cells when the population density exceeded 2.3 workers/ml
  • The number of queen cell that were constructed correlated with worker density. So the greater worker density resulted in greater numbers of queen cells.

Increased Comb Congestion
  • When more than 90% of the brood comb was occupied, workers began queen rearing.
  • Colonies with congested brood comb swarmed earlier than colonies with less congested brood comb.
  • Even though colonies with congested brood comb swarmed earlier, colonies with uncongested brood comb will sometimes swarm. So congestion is not necessary for swarming. 
Younger Population
  • Colonies that swarm have younger bees overall.
  • However, simply shaking a lot of younger bees into a hive will not trigger swarming.
Decreased Queen Pheromone
  • When the colony is congested, the queen does not spend as much time in the outer edges of the brood nest.
  • It's possible to reduce queen cell construction by applying QMP (queen mandibular pheromone) on the edges of combs.
  • In large colonies, fewer workers have detectable levels of QMP.
  • In congested colonies, swarming can be delayed by applying QMP.
Swarm Control through Nectar Management

Note, at this point, I'm going to stop sharing notes and simply share what happened along with my own musings.

Dr. Seeley passed out copies of an article written by Walt Wright on the subject of nectar management (i.e., checkerboarding), which we all read and discussed. You can read a number of articles by Mr. Wright online. These articles include a description of checkerboarding, including what it is and how it is done.

Checkerboarding is a technique that prevents swarming in Langstroth hives by providing empty space above the brood nest. This is done by alternating empty frames with full frames of honey in boxes above the brood nest. The timing of checkerboarding is also critical since it needs to be done before the first hardwood blooms. Here is an easy-to-read synopsis of it.

Since checkerboarding is a practice that's really designed for Langs, I won't go into it in much detail here. However, I do think it's interesting to think about how it might be applied in a TBH. I've seen TBH management diagrams that recommend alternating full and empty bars in the honey area of a TBH during a strong flow. However, don't think that this encourages the kind of massive comb-building that checkerboarding does.

What do you think about it? Have any thoughts about how it could be applied in a TBH setting?