Colony Clustering… Why Fall Has Been My Bees' Most Dangerous Time of Year

How many bees are needed to maintain optimal temperatures over winter?
This is very hard to estimate for the beekeeper. It varies by length of
confinement and regional temperatures that also vary.

We are learning new facts about bees all the time but this information from past published research on honey bees has served me well. Corrections always welcome:
  
3 Important Autumn Temperatures in Northern New England:

#1 - AIR TEMPERATURE OUTSIDE OF HIVE:

• 64°F: honey bees begin to cluster to keep the queen and themselves warm
• Nighttime temps: 45-57°F - worker bees cast out drones to protect food reserves
• 57°F: honey bee family cluster becomes more compact
• 45°F: Guards may be disabled. Predator insects like wasps are free to assault the hive until the first or second killing frost
• 23°F  bees generate warmth inside by vibrating their thorax in the cluster

#2 - INDIVIDUAL BEE TEMPERATURE:

• 57°F: Too cold to fly from a still start, or “Coma” threshold, however when muscles are “warmed up” can fly in colder temperatures and will try to forage. This can result in great losses in population when as many as 2/3 of a colony's adult bees go out as foragers, flying farther to find food in a barren landscape during short daylight hours with dropping temperatures.
• In clustering temperatures "Heater bees" crawl inside of empty cells, vibrating their thorax muscles to keep the surrounding cells warm. Empty cells serve a purpose.
• One single heater bee is thought to have the ability to keep up to 70 adjoining cells warm.

#3 - CLUSTER TEMPERATURE

• 95°F: optimal core temperature.
• 81°F: average temperature inside of a cluster.
• 48°F: average temperature exterior shell of cluster.
• 100°F: highest recorded temperature of a cluster.

How much honey to leave? 60 to 120, depending
on the colony, is my practice.

Thoughts: Mild outside temperatures in autumn + no forage = robbing behaviors and/or dwindling populations when foragers fly farther to find food in a barren landscape during short daylight hours with dropping temperatures. 

The death of honey bee foragers from cold and mowing practices in the country often leads to failed clustering efforts. This sets colonies up for attack from the high wasp populations - and with low native insect populations becoming the norm, wasps are all the more a threat. (For mowing impacts on colony loss see "Apimondia Istanbul - Promoting Bee Friendly Farming Methods - Walter Haefeker".

In my experience, bees protecting brood may not break clusters to protect food reserves from being robbed. Once the adult population has dwindled out the nurse bees stand little if any chance of compensating for their loss or surviving into winter. Often all that is left of a cluster after such events are the queen and a few attendants. To read more on this pheromone driven phenomenon: See Randy Oliver's "Old Bees, Cold Bees, No Bees" Part 1 and Part II."

What can the beekeeper do?

• Use robbing screens and set up open feeding stations away from hives to discourage robbing. This may also serve to distract wasps. See Guelph University's video of Beekeeper Paul Kelly on feeding bees.
  

• Monitor fall colony populations and food reserves. In cold weather this means paying attention to outside activity. Some beekeepers weigh their hives before & after a flow. Research ways to use a scale without being intrusive:
• Northern healthy honey bees generally consume 10-12 pounds of food a month. 
• Error on the side of southern honey bee appetites and leave or help your bees create 15 to 20 lbs of food per month for overwintering colonies.

• Monitor wasp activity. Destroy nests when necessary. Pollinator gardens may help. I seem to be discovering that a garden attracting a diverse pollinator population all season long, near my colonies, results in animals that prey on wasps and wasps not so intent on assaulting my hives.
  

Ideal temperature-driven behaviors when the nectar and pollen flow are over:

Thermal imaging is great,
but don't rely on these images alone.
Know your colonies.

• The colony population should be sufficient enough to maintain a core temperature of 95°F with an outer layer of population maintaining a temperature of 48°F. If you can take a peak with a thermal camera, fine, but rely on your familiarity with the colony. When in doubt, and we always are, research combining and overwintering strategies for small clusters.
  
• “heater bees” vibrate thorax muscles to raise body temperature 16° higher than normal 111°F. Bees along the outer shell of the cluster remain motionless, conserving energy and acting as a layer of insulation. Don't let motionless fool you into assuming they are dead. Many hives have been dismantled into the snow and cold that may have otherwise survived if the beekeeper only understood the girls' talents and dedication to colony survival.
• Warmer bees (95F) from the inside of the cluster, tucked into comb cells, continually change places with the colder bees (48°F) along the outer edge of the cluster to allow the colder bees, who have been eating, to warm up and “burn” off respiration. So the girls do not necessarily have their little legs crossed all winter waiting to void. See this very dry but fascinating YouTube from the UK's National Honey Show: Ben Harden. Excellent Bee Culture article: Winter Management
  

Thank you for caring enough about your bees to spend time reading such information as your fellow beekeepers can share in blogs. Despite the abundance of information on the web, it has always been the tradition of beekeepers to teach this craft by carefully sharing what they think they've learned when interacting with, and especially keeping alive in our climate, these brilliant and ancient, productive animals.

Honoring The Wildness

Saturday's CABA Bee School instructors were impressive, the class filled with engaged & practiced newbees & not-so-newbees. Always thought-provoking to interact with other beekeepers.

Missy from a Troy Hall nuc, 7am on a bright, spring day
and already back with the goods.

When asked many curious questions, I must have appeared vague about my so-called "treatment-free" practices, but there should be a round table about that subject sometime at bee schools because, like most management plans, it is usually unique to the beekeeper, their bees & their environment.

Someday, I hope very soon, we can stop talking about - and arguing about - varroa and celebrate instead the amazing honey bee and all the wonderful gifts evolution has brought about in her.

I wanted to be a beekeeper to take advantage of a colony's willingness to let us lean in close and interact with their wild natures. All I've ever sought to do is honor that wildness and enjoy the privilege. 12 seasons in, continually fascinated, never bored, and truly love being a part of beekeeping culture.

Common Honey Bee Pheromones

by Athena Contus, Athena’s Bees – April 2017
This is dealt with in many places on the web, but I'm just hoping to simplify it here for my students with some important links.

There are two types of pheromones: releaser and primer pheromones.

Releaser pheromones are odors that are fast-acting and behavior-changing, like the smell a bee leaves as a mark on a threat when it is alarmed.

Primer pheromones function much differently: they induce delayed, behavioral or psychological responses. Female worker bees do not lay eggs because they are under the spell of a primer pheromone released by the queen.

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Alarm pheromone – Smells like bananas

The alarm pheromone emitted when a bee stings another animal smells like bananas. Smoke can mask the bees' alarm pheromone.

The other alarm pheromone is released by the mandibular glands and consists of 2-heptanone, which is also a highly volatile substance. This compound has been found to anesthetize some intruding insects for about nine minutes.

Nasonov pheromone – Smells like lemongrass

Nasonov pheromone is emitted by the worker bees and used for orientation and recruitment.

Brood recognition pheromone

Prevents worker bees from bearing offspring in a colony that still has developing young. Both larvae and pupae emit a "brood recognition" pheromone. This inhibits ovarian development in worker bees and helps nurse bees distinguish worker larvae from drone larvae and pupae.

Drone pheromone

Drones produce a pheromone that attracts other flying drones to promote drone aggregations at sites suitable for mating with virgin queens.

Footprint pheromone

This pheromone is left by bees when they walk and is useful in enhancing Nasonov pheromones in searching for nectar.

In the queen, it is an oily secretion of the queen's tarsal glands that is deposited on the comb as she walks across it. This inhibits queen cell construction (thereby inhibiting swarming), and its production diminishes as the queen ages.

Forager pheromone

Ethyl oleate is released by older forager bees to slow the maturing of nurse bees. This primer pheromone acts as a distributed regulator to keep the ratio of nurse bees to forager bees in the balance that is most beneficial to the hive. For my beekeeping this has proven to have a great deal of impact on colonies going into winter. If fields are mowed when possibly two-thirds of my bees are out there foraging, they will be mowed down, returning to the hive in such small numbers a domino effect causes the dwindling phenomenon. See Randy Oliver's "Old Bees, Cold Bees, No Bees". Randy oddly does not mention mowing as a reason for foragers not making it home, but this is what I see and it was addressed at the Apimondia International Beekeeping Conference in Istanbul, 2017, Promoting Bee Friendly Farming Methods - Walter Haefeker

Movement & Honey Bees

By Athena Contus, Athena’s Bees – April 2017
photos: Creative Commons
 
A common sight on a hive landing board is a little bee or several with their little bee butts in the air.

This is where the nasonov gland is located. As the bees fan it with their wings, it gives off a smell similar to lemongrass. 

It says to the homeward bound bee:

“Here we are – don’t bee lost”.

Another common site is a small battalion of young bees hovering & flying in short spirts, while facing the hive. The guard bees hustle them out to practice these “orientation flights” whenever a safe window of opportunity presents itself.

Honey Bees are excellent navigators – even on a cloudy day they utilize the polarized light of the sun to get around; many colony dynamics come into play for success.

Navigating serves two purposes for the honey bee: Do the job – Get home.

The beekeeper needs to appreciate the following facts about honey bees & movement:

•    Moving a hive is very problematic because honey bees are very location specific. The landing board they leave from is in the only place they know to return to whether it is still there or not.

•    If during the day a beekeeper moves a beehive that has flying foragers, those foragers will come back to the base the hive sat on. It is the only location for “home” they have oriented to. Methods for moving hives must be carefully thought out by the beekeeper. Many are discussed in online beekeeper venues.

•    Bees cannot navigate without the polarized light of the sun so, unlike bumble bees, do not do well in a greenhouse or any house but their own.

•    The honey bee’s day is done at dusk. They cannot navigate in the dark. Night lights confuse them.

•    If trapped in a house or a car they will go immediately to a window toward the outside light trying to get home.

•    Bees may drift to other hives by mistake if they can’t recognize the home hive from the others in the apiary. If they have food with them they are welcome; if not, they are expelled & unless they can smell the difference between their home and the neighboring hive, they are lost.

•    In winter honey bees can be confused by a wrapped up hive when coming back from voiding waste. They often try and find their way under winter wrappings in vain. They can become exhausted, dying in the snow while looking for home.

•    There are no nasonov fanners on the landing board in winter. Some beekeepers do not wrap the front of the hive to avoid confusing the bees or concealing its uniqueness in the apiary.

We didn't get to this subject in our last club Bee School. This subject is often seldom addressed in books and lectures as well. 

Newbees In Club Bee School

Another winter and new beekeepers in Bee School 2019... Here are some things worth mentioning with a link to a past article or two...

Slatted racks were designed with great insights into northern honey bee behaviors. The book we are using for bee school this season reveals some confusion about what Slatted Racks are most useful for:

1. Giving the girls a place to hang out in increment spring cold & rain instead of crowding up into the brood box.
2. Buffering the brood box from any forager traffic as well as air breezing up through the screened bottom board.

Painting a beehive is fairly straight forward:
How To Paint:

• ONLY THE OUTSIDE OF THE HIVE!
• ONLY THE PARTS THAT DON'T TOUCH!
• That's basically it.

The hive parts that touch each other must be paint free. Paint only the outside surfaces for weather proofing the wood. The bees will propolis the insides. The landing board may be completely painted as it does not touch the bees nor need to be removed during an inspection.

Read more detail at this link.

What to use:  Exterior Paint, Latex. The photos above are with a weatherproofing stain, VOC less than 100. Drying time well over a few weeks before installing bees.

In our northern climate I make sure I can use it in cold weather. 

• Bees see only in the ultra violet range.

we see	bees see	add in UV
red	black	uv purple
orange	yellow/green*
yellow	yellow/green*	uv purple
green	green
blue	blue	uv violet
violet	blue	uv blue
purple	blue
white	blue green
black	black

What does this mean? Colors look different and they are attracted to our Purple, Violet, then Blue in that order. Red doesn't work for them. White looks bluish-green to them.