Friday, February 19, 2021

Winter Tests Bee Colonies

 


Winter weather tests honey bee colonies and the beekeepers who set up the hives last fall. This year’s cold temperatures and heavy snow contrasted with recent years which saw mild temperatures and very little snowfall. Winds that normally swirl around the arctic, known as the polar vortex, took a dip deep into the South. Southern states recorded the coldest temperatures in years, and Arkansas and much of the South was blanketed with snow. Honey bees have the same requirements as humans: a warm, dry house, food, water, and an environment free of toxins. When beekeepers set up their hives for the winter, they make sure that the bees have plenty of food, placed where the bees can access it. Especially in the winter, bee hives must have adequate ventilation; hives must be able to vent considerable amounts of water vapor. Honey bee respiration produces water vapor, and water from condensation dripping in the hive can kill bees. With air entering bee hives through screened bottom boards or hive entrances, a small vent in the inner cover allows moist air to escape. Snow covering the entrances is porous and should allow air to enter the hives; however, bees must wait for a snow melt or the beekeeper’s clearing of hive entrances to make cleansing flights.

 

Bee hives are by design resistant to winter weather. Cold winds are dampened by parallel sheets of honeycomb, and empty comb cells hold dead air, providing natural insulation. In the South, wrapping of hives and closing screened bottom boards is generally unnecessary. New beekeepers learn the necessary hive preparation techniques from seasoned beekeepers in their area. Regardless of the beekeeper’s care in setting up hives for winter, there are often some colony losses. The majority of these losses are due to starvation. Bees are capable at regulating temperatures in the hive, but starvation often results from small wintertime bee clusters not being able to move about the hive in extended cold weather to access stored honey.

--Richard

Friday, February 5, 2021

Winter Hive Walk Around

 


Beekeeping involves observing hives from the outside as much as on the inside. Beekeepers can’t risk opening hives for a thorough examination during cold weather, but we should occasionally visit the hives during cold and inclement weather. Much can be told of the condition of the colonies inside the bee hives by observing from the outside. Bees do not venture outside the hives when temperatures are below 50 degrees Fahrenheit. They remain inside, clustered together to retain warmth. Honey bees eat their high-energy food, honey, and generate heat in their flight muscles. Only on warm days, bees venture from their hive to make cleansing flights to eliminate their body waste. You will see forager bees that are collecting water, nectar, and pollen. Observing foragers returning to a hive carrying pollen on their pollen baskets of their hind legs usually indicates that their queen is laying eggs. Finding some dead bees on the ground in front of the hives is normal, as a number of bees die inside the hive every day, and they are removed from the hive. A foul odor at a hive may indicate a dead colony with a large number of bees decaying on the hive’s bottom board. If the air temperature is close to 50 degrees, the beekeeper may briefly open a hive’s cover to see if the bees are alive. If the colony has died, the beekeeper needs to protect the combs so that they will not be destroyed by hive scavengers.

 

On my hive visit today, I observed bee pupae on the landing board at the entrance to one hive as seen here. Likely, the workers are aborting brood infested with parasitic Varroa mites. A genetic trait, called hygienic behavior, allows workers to detect Varroa developing with the bee pupae and abort the bee and mites. When the weather warms enough for me to open the hives, I will measure the mite loads and apply an appropriate treatment if the mites exceed prescribed thresholds.

--Richard

Thursday, December 24, 2020

Pax Vobiscum


The year 2020 has been dominated by the Covid-19 virus. Viruses are infectious agents, smaller than bacteria, that infect all types of life forms, from animals and plants, even microorganisms. Millions of viruses exist; some infect a narrow group of hosts, and others infect a wide group of hosts. Viruses are carried, or vectored, from one host to another by a number of means. For example, viruses are passed between plants by chewing insects, and viruses causing the common cold are passed airborne between humans when infected people cough or sneeze. Humans and honey bees are affected by a number of viral diseases. Beekeepers fight the ill-effects of viral diseases of honey bees to maintain healthy colonies, aware of sacbrood disease and bee paralysis, caused by viruses, as well as Kashmir virus, black queen cell virus, and deformed wing virus. At least 50 viruses vectored by parasitic Varroa mites have been identified.

Humans are affected by a number of viral diseases including chicken pox and the common cold. A number of viruses exist in both honey bees and humans without doing harm to their host. However, a new virus, known as Covid-19, entered the human population and spread rapidly around the world this year. The highly contagious virus killed 300,000 people in the U.S. and sickened many more. Persons are susceptible to becoming ill after exposure to the Covid-19 virus unless they have developed an immunity either by having the disease and recovering or by receiving a vaccine. Vaccines for Covid-19 are being developed and distributed. Currently there are no vaccines to protect honey bees from the many viruses that are vectored by Varroa mites. The only effective means of protecting either humans or bees from viruses is to maintain a distance from the vector. With humans, that means wearing masks, maintaining separation, and isolation. With bees, it means controlling Varroa populations. Mindful and saddened by our losses to Covid-19, the Underhills of Peace Bee Farm wish peace be with you.

--Richard

Saturday, November 21, 2020

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

Monday, October 19, 2020

Bees Identify Nest Mates

 


Drones are the male reproductive members of the honey bee hive. Drones perform no work in the hive and have but one duty: They mate with queen bees. In the Mid-South, colonies produce queens from April through August, and these queens mate a few days after queens emerge as adults. Since drones serve no purpose to the bees during the winter, colonies drive all drones from the hive in the fall. Removing non-working drones from the hive helps conserve winter food stores and ensure colony survival. There is one instance, though, when drones are not removed from the hive. Queenless colonies often retain their drones through the winter. While making a recent inspection of my hives, I found that most of the drones had been driven from the hives. However, one hive held a number of drones, a situation that calls for further investigation. Normally, beekeepers don’t need to find a queen, only evidence that the colony has one and that she is laying eggs. In today’s photo, we see the queen, a healthy, young queen, marked in blue. This queen was introduced into the hive in late summer, and she is laying plenty of eggs. A number of drones, bees larger than the workers, are visible in the photo.

 

An important part of our fall hive set-up for winter involves determining that every hive has enough honey to sustain the colony through the winter. With decreasing forage available for the bees to make honey, bees will readily rob honey from any hive if its colony is too weak to defend itself. Every hive is protected by guard bees that check bees attempting to enter. Bees not belonging to the colony are rejected by the guards. Researchers at Washington University in St. Louis found a mechanism for bees identifying hive mates. See https://phys.org/news/2020-10-gut-bacteria-key-bee-id.html?. They found that bacteria in the bees’ gut affects the odor of the bees’ exoskeletons. Guard bees identify bees belonging in their hive by their distinct odor.

--Richard

Saturday, September 19, 2020

Donkey Days of Summer


I met Elvis Opris, the owner of Brothers Honey Company, https://www.facebook.com/brothershoneyco, in his bee yard, and we started our day early with a breakfast of coffee and graham crackers on the tailgate of my truck. As I lit the smoker, a pair of donkeys, guardians of the farm’s livestock, invited themselves to join in on eating our graham crackers. After the harvest of the summer’s honey, it was time to perform a thorough inspection of the bee hives and start any needed treatments for parasitic mites. As with all hive inspections, we checked for obvious hive diseases and evidence that each hive had a prolific egg-laying queen. In the late summer and early fall seasons, queens lay fewer eggs, and bee populations begin a slight decline. Parasitic varroa mite populations, however, reach their annual maximum. It is important that beekeepers determine the number of mites in the hives and treat the hives if their mite loads exceed recommended thresholds. Information on testing methods, treatment thresholds, and appropriate mite treatments are found on the Honey Bee Health Coalition’s website, https://honeybeehealthcoalition.org/varroa/. Many of the available mite treatments have restrictions on their use. For example, to prevent contamination of honey by chemical treatments, most cannot be used when honey supers are on the hives. Some treatments have temperature restrictions, and need to be applied in the fall with cooler temperatures.

 

We measured the mite loads on hives that had stayed on the farm throughout the year using an alcohol-wash test and found varroa at close to the treatment threshold. Other hives that had been moved to another location for honey production returned in weakened conditions with a large percentage of colonies dead. We measured these surviving hives and found mite loads above the treatment thresholds, so we applied a treatment to all hives. We will measure the mite loads again during the fall to see if the treatments brought the mites below recommended thresholds. I suspect that the donkeys will expect graham crackers.

--Richard

Saturday, August 22, 2020

Dog Days of Summer


The hot, droughty mid-summer period is often called the Dog Days of Summer, and a significant dearth of nectar often exists from July through September. At this time, locations that produce spring honey see a dramatic reduction in honey production. Bee hives located near agricultural crops continue to produce honey, especially if the crops are irrigated. Summer’s dearth is a time for harvesting spring and summer honey before fall wildflowers come into bloom. Typically, honey produced from flowers early in the year are mild in flavor and aroma, while honey produced in the fall is          quite more pronounced. Honey bees do not bring into the hives as much nectar and pollen during the summer’s dearth, however, they forage a considerable amount of water. In today’s photo, honey bees are foraging water from moss-covered rocks and duckweed in the bee yard’s water source. A short high speed video shows how the honey bee uses its tongue to take in water either by lapping or by sucking: https://www.nytimes.com/2020/08/11/science/honeybees-drink-video.html. Beekeepers should make sure that their hives have a reliable source of water throughout the year, and this is especially important in the heat of summer when bees use water to help cool their hives.

The Dog Days of Summer are a good time to take care of other bee hive issues. Small hive beetle populations often expand during the heat of summer. If unchecked, the beetles can overwhelm bee colonies. Integrated pest management approaches to beetle control include hive placement in the sun, beetle trapping, and minimal hive manipulations. Beekeepers should try to prevent multiple generations of beetles from existing in the hives before wintertime. Late summer is a good time to provide pollen substitute feeding to stimulate the queens to continue to lay eggs. It’s important that beekeepers plan for controlling varroa mites as soon as the honey is harvested and temperatures cool to within treatment limits. Consult the Honey Bee Health Coalition’s Varroa Management Decision Tool: https://honeybeehealthcoalition.org/varroa/.
--Richard