Bees are Foraging Propolis

Honey bees and beekeepers are preparing hives for winter. One of the bees’ hive preparations involves collecting propolis. Bees gather resins and gums from trees to produce propolis, the antimicrobial “bee glue” that they use to varnish their hives. The bees seal all unwanted openings in the hive with propolis to block entrance of unwanted insect intruders. Cracks inside the hive, smaller than a bee space of three eights of an inch, are filled with propolis. This includes the seams between the several boxes that make up a modern bee hive as well as the space along the edges of hive frames. A sturdy beekeeper’s hive tool is required to break the propolis bonds of individual boxes and frames. Propolis is sticky in warm weather and brittle when cold. The bees in today’s photo are foraging propolis warmed by the sun. Bees use the propolis to control unwanted drafts inside their hive, even building propolis plenums in the hive to block chilling winter air flows. Guard bees drive small hive beetles into sticky propolis “jails” to help control these hive pests. The antibacterial and antifungal propolis is an important element in the honey bee colony’s health. If a hive invader, such as a mouse, cannot be removed by the bees, they will encapsulate the dead body in propolis to prevent the spread of bacteria in the hive.

 

Inside the hive, worker bees are concentrating the honey from cells high in the hive to cells closer to the brood nest. While the bees continue to forage for fall nectar, beekeepers need to ensure that every hive has adequate honey stored for the winter. The essence of beekeeping is to tend to healthy colonies and not get too greedy when robbing the hives. If a beekeeper takes too much honey from a hive, the colony will starve over winter. How much honey should one leave on the hives? The answer comes from the shared experience of beekeepers in the local area.

--Richard

The First Frost

The first frost of the year came two weeks earlier than normal, but the cold night didn’t bother the honey bees in their warm, dry hives. Their hives are already set-up for winter with the brood nests centered low in the hives and plenty of frames of honey above and to the sides. Ventilation ports are open to draw off damp air from the top of the hives to prevent a build-up of condensation. Screened bottom boards are open. Ensuring that the hives have enough stored honey located where the bees can access it and providing ventilation are the only requirements for wintering bees in Arkansas. Whenever the temperature drops to 57 degrees Fahrenheit, the bees draw into a cluster for warmth. They consume their stored honey and generate heat in their flight muscles to warm the cluster. The hives have plenty of food in storage.

With clear skies, the afternoon sun brought the temperature up rapidly. As the air temperature rose above 50, the bees poured out of their hives for cleansing flights and foraging. Many bees were bringing in pollen from bitterweed, goldenrod, and fall asters. The sight of bees foraging for pollen usually indicates that the queens are still laying eggs and the nurse bees are feeding larvae. Other workers were bringing in fall nectar, producing strong flavored honey for the winter. A few bees could be found on lily pads foraging for water, and a some were gathering wood sap and gums for propolis. The bee in today’s photo is struggling to forage some propolis. She will use this bee glue to seal off any hive cracks. The bees will even build barriers of propolis inside their hives to reduce entrances or to block cold drafts. Only a few drones were seen at the hive entrance. Most have been excluded from the hives. Only queen-less hives will keep their drones into the winter. It is too late in the year for the mating of queens.

--Richard

Propolis for Bee Health

Propolis is one of four substances, along with nectar pollen, and water, that foraging honey bees bring into their hive. The collection of propolis is an important colony protection behavior. Bees collect propolis from the sap, gums, and resins of trees, often evergreens. The sticky substance is used to seal cracks and small openings in the honey bee colony’s hive. It is the “bee glue” that attaches beeswax combs to the hive. When a swarm of bees moves into a hollow tree cavity, or when a beekeeper hives a colony in a new hive, the bees varnish the inside walls of their new home with propolis. Not only does the propolis provide a protective barrier against drafts and moisture, it also provides antimicrobial protections. Foraging bees returning to their hive walk across an antibacterial and antifungal “door mat” of propolis deposited at the hive entrance. Honey bees use propolis to help protect the colony from invaders. Bees entomb with propolis dead mice or intruding insects too large to drag from the hive, preventing the spread through the hive of bacteria from decaying pests. Bees also trap Small Hive Beetles in propolis “jails” within the hive.

The behavior of collecting propolis is a heritable trait. Some beekeepers in the past considered manipulating heavily propolized hives unnecessarily messy, and therefore selected for bees that collected little propolis. However, colony health benefits of having plenty of propolis in the hives makes it advantageous to encourage propolis collection. An article published in the Journal of Economic Entomology, https://entomologytoday.org/2018/11/28/propolis-how-beekeepers-encourage-better-hive-health/, describes how researchers tested several means of roughening the interior of bee hives to encourage bees to fill small openings with propolis. I regularly roughen new hive boxes with a steel brush and a jagged flint rock from Arkansas’ Boston Mountains. Researcher Dr. Keith Delaplane, entomology professor at the University of Georgia, describes encouraging bees to deposit extra propolis as partnering with biology. In today’s photo bees eagerly gather and reuse propolis from a recently opened hive.

--Richard

A Bee Hive Cut-out

Beekeepers Jim Metrailer, Jeremy Bemis, and I removed a colony of honey bees from the wall of a building and transferred the combs and bees into a Kenyan Top Bar Hive. Bees often find the empty space between the inner and outer walls of buildings as suitable cavities for nesting. Indeed, wall spaces are quite similar to cavities in hollow trees, the natural home of honey bees. We exposed the combs of the colony’s nest by removing the building’s weather boards as shown in today’s photo. The entrance into the bees’ hive, a small opening between the removed boards and the remaining boards on the right, was coated with propolis. This sticky substance, with antibacterial and antifungal properties, helps protect the hive from harmful pathogens. One can often identify a bee tree, a damaged tree with a hollow cavity housing a feral honey bee colony, by a dark, shiny propolis stain surrounding a knot hole where the bees enter the tree. The same shiny stain can also be found where bees enter the walls of a building. Honey bees varnish their hive with propolis, a substance that they gather from the gums and saps of trees. The layer of propolis is particularly evident on the rough-hewn weather boards. When we build bee hives, rough interior surfaces encourage the bees to build-up propolis on the wood to protect the hive. The somewhat pungent odor of propolis surely adds to each hive’s distinct odor.

When we cut the combs out of the wall of the building, we sorted the combs according to their use by the bees. Some held brood; some pollen and bee bread; some held stores of honey. Using strings, we tied the combs onto hive top bars and placed them in the new hive. The Top Bar Hives was arranged as a natural bee hive with the brood near the entrance surrounded by pollen and bee bread. Combs of stored honey were placed in the rear of the hive.

--Richard

Products of the Bee Hive

Honey bees are managed for pollination service and for production of honey. The honey bee hive also produces a number of other valuable products. The Tennessee Beekeepers Association conducts a series of workshops across the state to train beekeepers in techniques for harvesting other bee hive resources and for making useful products from them. The beekeepers examine various pollen traps used to collect pollen. The traps work by brushing some of the pollen pellets from the pollen baskets on the legs of worker pollen-foraging bees. The collected bee pollen is a complete protein containing all of the necessary amino acids as well as all known vitamins and 25 trace elements necessary for mammals. In North America, the majority of collected bee pollen is fed to livestock. Some trainers feed large quantities of pollen to race horses. The beekeepers also discuss various methods of collecting propolis, the antiseptic, antimicrobial, and detoxifying bee glue that has been used for at least 2000 years. Propolis, the material that honey bees use to varnish their hive to inhibit wood-rotting fungi, disinfect cells before the queen lays eggs, and reduce the growth of numerous strains of pathogenic bacteria, is collected and sold for use in the production of medications.

The text that the beekeepers use in the sessions on producing value-added bee hive products, Health and Healing with Bee Products by C. Leigh Broadhurst, also lists health benefits of honey. The author, a USDA research scientist, explains that honey is a broad-spectrum antibiotic; it is antifungal and antimicrobial; and it is sometimes mixed with propolis for wound treatments. Broadhurst also reveals that the vitamins, minerals, and enzymes present in honey aid in metabolism. The beekeepers also use beeswax to make candles and skin-care products. In today’s picture beekeepers pour beeswax into candle molds. The training sessions are funded by a grant from the Tennessee Department of Agriculture which recognizes the importance of increasing beekeeper income to ensure continued honey bee availability for crop pollination.

--Richard

Bees Make Cleansing Flights

The winds changed directions today. A southerly wind brought warmer conditions, and the bees were able to break out of their cold-weather cluster and fly from their hives. As soon as the air warmed, bees poured from the hives for cleansing flights. Honey bees generally don’t fly until the air temperature rises to 50 degrees. Cold weather for the past few days has held the bees in their hives. After several days of confinement, the bees were ready to make a cleansing flight to eliminate their body wastes. Honey bees never defecate inside their hive. This is one of their behavioral traits that serve to help prevent disease from spreading through the colony. Honey bees maintain a clean nest as a healthy place to raise their brood and store honey. Worker bees varnish the hive and seal cracks and openings with a coating of antibacterial and antifungal propolis bee glue. Worker bees clean debris from the hive and guard bees attack and kill intruding wasps, hornets, yellow jackets, and honey bees from foreign hives. Workers remove these dead insects as well as honey bees that die within the hive. Sick bees leave the hive to die, and diseased bees are turned away at the hive entrance by guards. Strong colonies remove the eggs and larvae of wax moths and small hive beetles from cells and out of the way corners of the hive. If a mouse finds its way inside the hive, guard bees sting and kill it; then, workers entomb the mouse in propolis.

One of the unexpected findings resulting from the analysis of the honey bee’s genome was the lack of complexity of the honey bee immune system. It was generally expected that an organism that has existed for millions of years would be protected by a complex immune system. It seems that the honey bee’s evolutionary path instead relied upon a number of behavioral traits to protect the colony from disease.
--Richard

Honey Bees Cluster

One of the reasons that honey bees have been so successful at occupying diverse territories is that they maintain the environment within their nest. Swarming bees begin by selecting a cavity of the appropriate size, about 40 liters. The bees varnish the new cavity with a thin coating of bee glue, called propolis, to seal cracks and make the nest somewhat waterproof. Next, the worker bees begin building sheets of beeswax comb in the cavity. The colony raises brood and stores food in the cells of the comb. The worker bees control the internal environment of the hive. Anytime during the year that brood is being produced, they maintain a hive temperature of about 95 degrees.

When outside temperatures drop in the fall, the bees form a cluster inside the hive to maintain heat. The cluster generally maintains a temperature of about 68 degrees. The queen bee stops laying eggs and rests in the center of the cluster. Clustered bees actually generate heat by eating their high-energy food, honey, and then vibrating their flight muscles to raise their body temperature, a unique feat for an insect. The cluster also adjusts its internal temperature by expanding or contracting as needed. However, if the outside air temperature is very cold, the bees must consume greater amounts of honey to warm the cluster. The bees are not wasteful; they don’t attempt to warm the hive space outside the cluster of bees. The structure of the honey bee nest is itself very favorable for winter survival. The sheets of comb make good insulation. As the honey is eaten from the cells, the cells of dead air become an exceptionally effective barrier from the cold. However, during very cold weather, honey bees often cannot break away from their tight cluster to feed. The colony may starve, even when honey is available nearby. Click the picture. Opening the hive on a cold morning, I disturbed a late fall cluster of bees.
--Richard

Honey Bees Guard Jails

Honey bees are resilient creatures. In the short time that the small hive beetle has been in the United States, the adaptable honey bee has learned to live with this invasive species. The small hive beetle entered this country in about 1999, probably as a stow-away in a shipment of cargo from Africa. Many invasive plants and animals are inadvertently carried around the world through trade. We first detected the small hive beetle in the Arkansas Delta around 2004. At first, the hard-shelled beetles seemed to have free roam of the bee hives. However, within a few months, I noticed that the honey bees’ behavior was changing toward the small hive beetle. The bees aggressively sought out the beetles, chasing them into distant corners of the hive. Whenever a honey bee could catch a beetle, she would hold it and fly out of the hive with it.

The honey bees quickly learned how to help control these insects that are protected by a shell tough enough to resist the bees’ bites and stings. They began to build jails in corners of the bee hive to house the beetles. These jails were actually small compartments constructed of bee glue, called propolis. A common location for a jail is the space between the end of each hive frame and the edge of the hive body. Click on the picture to see guard bees tending to their captured small hive beetles trapped in one of these spaces. On the right side of the photo, a small hive beetle tries to escape. You can see the head and thorax of the dark brown colored beetle. Its antennae look like they have balls at the ends. These balls are actually sensitive feather-like structures. Since the bees cannot kill the invading small hive beetles, they resort to containing them in the hive, preventing their reproduction in the cells of stored pollen. The honey bees will even feed their captive small hive beetles.
--Richard

Bee Hive Products

The honey bee hive produces a number of products that are useful to man. The first is, of course, honey. We know from cave paintings that men have been taking honey from bees for at least seven thousand years. Rita gave a presentation on the products of the bee hive to an interested group at the Collierville, Tennessee library. The next product of the bee hive is beeswax, which is the material from which the comb is made. Beeswax is secreted by glands on the underside of the young bees’ abdomens. Beeswax has been used extensively by man. High quality beeswax candles have always been a church tradition. Beeswax strengthens thread for sewing and bowstrings for archery. Beeswax was used extensively aboard ships, especially as a lubricant. Mixed with other waxes and oils, beeswax can be converted into many products from furniture polish, to boot and saddle conditioner, to lip gloss and hand lotions. Bee pollen is a high-protein hive product eaten as a food that contains vitamins and minerals. Propolis is the antibacterial and antifungal bee glue that honey bees make from the saps and gums of trees. It is harvested from the bee hive to produce medicines for man. Antonio Stradivari used propolis in the late 1600s when he built violins. Royal jelly is collected from the queen bee cells and is eaten by humans. This food of the queen bee is collected in tiny amounts, mostly in China. Almost none is collected in the United States. The products of the bee hive are sources of hundreds of items used by man.

Today’s picture is button bush, a shrub which thrives in the Arkansas Delta at the water’s edge. Button bush has an open, unprotected flower, which attracts a number of insect species. Click on the picture to see a honey bee sharing a button bush flower with a butterfly. A tiny solitary bee rests nearby.
--Richard

Honey Bees Collect Propolis

Honey bees bring four things into the hive: nectar, pollen, water, and propolis. Propolis is sometimes called bee glue. Honey bees collect the saps and gums of trees to make propolis. Propolis is a sticky substance with the texture of chewing gum found on the sole of your shoe. The bees use it to glue together everything in the bee hive. It is the reason that beekeepers use a hive tool to open the hive and remove the frames. The bees use propolis to seal every crack in the hive. When they first move into a hive or cavity, they varnish the inside surfaces with propolis, which has antibacterial and antifungal properties. As well as sealing cracks, the bees build structures with propolis to direct the flow of air through their nest. If a mouse gets into the bee hive, the bees will often sting it to death and then encase the dead body in propolis, thus protecting the hive from bacteria and odor.

Propolis has a number of human uses as well. A number of medications are made from propolis. It is also applied to the surface of certain musical instruments. It is thought that Antonio Stradivari used propolis in making his violins in the late 1600s. Click on the photo to see the honey bee collecting propolis. It is a difficult task, taking considerable time. The bee gnaws at the sticky tree sap with her mandibles to free flakes which she carries in her pollen baskets. The propolis is the yellow flakes on the bee’s hind legs. Once she returns to the hive, she will need the assistance of another bee to remove the sticky propolis from her pollen baskets. Even for the bees, propolis is almost as sticky as chewing gum.
--Richard