Sampling Varroa Mites

Varroa mites are the greatest pest killer of honey bees. If left unchecked, these parasites will kill a colony of bees in about 18 months. It is, therefore, necessary for beekeepers to be aware of the mite load that a hive carries and to take corrective action when mite numbers exceed critical levels. Varroa mites live in bee hives, and they reproduce in the sealed brood cells of the pupal stage of honey bee brood. Mite levels typically peak in late summer at the time that queen bees slow their rate of egg laying. Excessive numbers of Varroa mites in the hive often lead to colony death. Mites weaken individual bees by sucking the bee’s blood, known as hemolymph. When a mite pierces the exoskeleton of a honey bee, it passes numerous viruses to the bee. At least 15 Varroa-vectored viruses have been identified. Varroa mites and the viruses that they transmit lessen the life span of the bees, leading to smaller winter colony clusters. These smaller clusters are often unable to generate enough heat to survive the winter.

Some individuals ignore the threat of parasitic mites and lose their bee. Others attempt to kill the mites with harsh chemical treatments. They are usually successful in reducing the colony mite loads, however, repeated use of harsh chemicals leads to populations of mites that are resistant to the chemicals. Beekeepers who take a judicious approach to controlling parasitic mites develop their own Integrated Pest Management program that involves mite sampling and treatments as necessary. The Honey Bee Health Coalition offers Tools for Varroa Management: A Guide to Effective Varroa Sampling & Control as a free document. The guide and video demonstrations of Varroa control techniques may be downloaded from http://honeybeehealthcoalition.org/varroa/. There are several methods of sampling a bee hive’s mite levels, including powdered sugar rolls and alcohol rolls. In today’s photo, Rita is counting the number of Varroa mites on 300 bees using a simple alcohol roll test.

--Richard

The Sun's Corona

Photographer, Mike Worthy, captured this picture of the sun at total eclipse showing the sun’s corona, the atmosphere of the sun. See NASA’s website: https://eclipse2017.nasa.gov/sun. The photo was taken August 21, 2017 at Marshall County, Kentucky. Thank you, Mike!

--Richard

Beekeepers Observe an Eclipse

An eclipse of the sun is a rare event. A total eclipse passed across the entire United States on August 21, 2017, the first such occurrence in nearly 100 years. Rita and I travelled to Marshall County, Kentucky to meet beekeeping friends, Shirley Murphy and Mike Worthy along the path of the moon’s totally shadowing the earth. The trip was worthwhile. The experience of observing a total eclipse is significantly different from witnessing the same event a short distance away in the much wider area of partial eclipse. The 70-mile-wide area of total coverage of the moon’s shadow affords researchers and photographers an opportunity to observe the sun’s structure in rare detail. It also provides a rare and awe-inspiring spectacle of nature for anyone in place. Mike Worthy, an accomplished photographer and amateur astronomer, photographed the eclipse. Here is Mike’s photo of the sun at total eclipse, showing solar prominences, red streams of hot gasses looping hundreds of thousands of miles out into the sun’s outer atmosphere. See NASA’s website for a description of solar prominences: https://www.nasa.gov/content/goddard/what-is-a-solar-prominence.

As the moon crossed in front of the sun, the sky slowly darkened. Within a few minutes of total eclipse the air cooled and colors shifted. August lawns turned a brighter green; Mike’s white car turned silvery gray. When the moon finally covered the sun, the sky abruptly darkened. The only light showing was an orange glow in the horizons. Planets and mosquitoes appeared. Song birds called, and crickets chirped. Beekeepers questioned how honey bees would react to light conditions darkening to nighttime at mid-day. Alert beekeeper, Brent Ferguson, along with three others in his bee yard in central Arkansas in the area of partial eclipse, watched the bee hives for any change in the bees’ behavior. There was no observed change in behavior. Did the foraging bees change their navigation from solar guidance to ultraviolet, magnetic, or odors? Eclipses are rare; honey bees are resilient and capable of operating in rapidly changing conditions.

--Richard

Water for the Bee Hive

Honey bee workers forage for four things that they bring into the bee hive: nectar, pollen, propolis, and water. Nectar is the sugary secretion of flowers that bees convert into honey. Pollen, also a product of flowers, is a necessary component of bee food that contains protein, fats, vitamins, and minerals. Propolis is a sticky substance that bees gather from the saps and gums of trees. It is the “bee glue” that honey bees use to seal cracks and openings in the bee hive, and, due to its antimicrobial properties, protect the hive from pathogens. Water is an important part of the life of a honey bee colony. Bees require water for metabolic processes; they use water to dilute stored honey for consumption in the hive; and they use water to help cool the hive. Honey bees are quite adept at regulating the environment inside the bee hive. Whenever there is brood in the hive, which is most of the year, the bees regulate the hive temperature to 95 degrees Fahrenheit. Bees must cool the hive in the summer. They do this in part by fanning their wings across droplets of water. With July temperatures above 95 degrees, the bees are foraging heavily for water.

A bee hive consumes lots of water. It is important for the beekeeper to ensure a reliable source of water for all bee yards. Unless an apiary is located near a natural body of water, like a lake or stream, artificial water sources should be provided. Because scout bees share the flavor of water that they find, bees prefer water with a taste. Bees will readily forage from pet or livestock watering containers.  Bees also like to collect water from swimming pools; and, for this reason, beekeepers need to provide an attractive water source close to urban hives as part of their Good Neighbor efforts. In today’s photo, honey bees float on duckweed and water lilies in my goldfish ponds to collect water.

--Richard

GMO Crops and Bees

New technologies are, rightfully, viewed with skepticism. One of our blog readers asks, “Is there any effect of transgenic crops on bees?” The use of genetic engineering involves transgenic material, a portion of one plant or animal, being inserted into another organism. The resulting plant or animal is described as being a “genetically modified organism,” or GMO. In the case of crops, the purpose of the transfer of genetic material is to produce a new crop with desired traits. A number of crops are regularly produced using transgenic technologies include corn, rice, soybean, cotton, and rapeseed. Some GMO crops, especially soybean, cotton, and canola (rapeseed), are regularly foraged by honey bees. Careful study continues to determine any effect that the planting of GMO crops that are food sources for honey bees will have on the health of the bees and the safety of the honey that the bees produce.

Currently, there are two principal uses of GMO technology used to produce agricultural crops. The first employs Bt (Bacillus thuringiensis) genes to produce a toxin in crop plants as a means of controlling insect pests. The second GMO technology in common usage is designed to control crop weeds. The herbicide glyphosate, known as Roundup, is in widespread use to control broad-leaf weeds and grasses. Genetically modified corn, canola, alfalfa, sugar beets, and cotton are resistant to glyphosate. The herbicide can be sprayed over the genetically modified, glyphosate-resistant crop plants and weeds, killing only the weeds. Neither Bt toxin nor glyphosate-resistant GMO technologies appear to be harmful to honey bees and other pollinators, nor do they contaminate honey. The use of glyphosate-resistant technology does have a negative effect on bees and insect pollinators when it destroys the weedy field margins that previously provided food and habitat for these insects. Today’s photo shows a GMO soybean field. Glyphosate herbicide killed the weeds and grass in the crop area and along the field margin, leaving soybean plants growing without competition.

--Richard

Reversing the Bee Hive

Throughout the spring, healthy honey bee colonies rapidly increase in population. This occurs as flowering plants are making nectar and pollen significantly more abundant. Both are collected by foraging worker bees and welcomed into the hive. The pollen is stored in close proximity to the brood nest where the queen is laying eggs and the workers are feeding and tending to the developing brood. The nectar, which will be converted into honey, is stored in the hive area outside the brood nest beyond the surrounding pollen. However, if there is not enough free honeycomb cells available, the bees will store the nectar in the brood nest. When this happens, beekeepers describe the hive as being “honey bound.” A serious hive problem results because the queen is left with no place to lay eggs. Prolific queens need at least 1500 empty cells per day to lay the eqqs necessary to sustain the colony’s population. As the brood nest becomes congested with nectar and honey, the colony starts making preparations for swarming. It is important for beekeepers to check for brood nest congestion and to take corrective action.

Honey bees cluster together and generate heat during cold weather. It is common for the cluster of bees to gradually move upward in the hive over the winter months. In the spring, beekeepers need to determine the position of the brood nest and the cluster of bees. Some colonies will move back down into the lower portion of the hive during the spring, but it is common for bees to remain in the upper half of the hive. This has the effect of the bees living in a hive of one-half its normal volume. Reversing the position of the hive bodies gives the colony greater capacity in the brood nest, providing cells for the queen to lay eggs. This is an important beekeeping measure in swarm suppression. Today’s photo: a queen bee on a honey-bound frame with capped honey, liquid honey, and pupa-stage brood.

--Richard

Swarm Season

Healthy honey bee colonies swarm. Swarming is the honey bee’s way of reproducing on a colony-wide basis. Honey bees typically swarm in the spring, and this season has been exceptionally “swarmy.” The Mid-South experienced a warm winter, and springtime weather arrived early. Warm weather and frequent rains brought plenty of wildflowers into bloom. Mild weather allowed the bees to take advantage of red maple and other early-blooming plants. Early-season pollen flows stimulated the queens to rapidly increase egg-laying in late winter and spring. Unless beekeepers expand the capacity of their hives in the spring by rearranging hive bodies and adding extra boxes of frames, hives tend to get congested with honey. Brood nest congestion, where the queen doesn’t have adequate numbers of cells to lay eggs, leads to swarming.

Beekeepers don’t like for their hives to swarm. The smaller resulting colonies don’t have enough bees to produce a surplus of honey. The effect of a hive’s swarming is that this year’s honey crop just flew away! However, beekeepers are often able to capture swarms of bees where they rest, often on a tree limb or structure like the wall of a house, before they fly away to a permanent nesting location. These captured bee colonies make for good replacements of winter hive losses. Captured swarms are particularly useful because the bees are especially capable of drawing out beeswax honeycombs. If the beekeeper feeds sugar syrup to a newly hived swarm, it will rapidly fill the hive with honeycombs. Captured bee swarms are a source of genetic diversity, and they may bring in desirable traits. Beekeepers should evaluate their swarm colonies and replace the queen if the bees show undesirable traits, such as excessive defensiveness. Today’s photo: young workers make orientation flights at the entrance to a hive of swarming bees captured in early April. Swarm catching can be quite exciting. A beekeeping friend, an avid outdoorsman, proclaims that he would rather catch a swarm of bees than a five-pound bass!

--Richard