Honey bees, like all other living things, have varying individual traits such as temperament, disease resistance, and productivity. The environment has a large effect on differences among honey bee colonies (for example, plants in different areas yield different honey crops), but the genetic makeup of a colony can also impact the characteristics that define a particular group. Beekeepers have long known that different genetic stocks have distinctive characteristics, so they utilize different strains to suit their particular purpose, whether it be pollination, a honey crop, or bee production.

The term “stock” is defined as a loose combination of traits that characterize a particular group of bees. Such groups can be divided by species, race, region, population, or breeding line in a commercial operation. Many of the current stocks in the United States can be grouped at one or more of these levels of biological organization, so the terms will be used interchangeably, depending on the particular strain of bees in question.

Wide variation exists within stocks as well as between separate stocks. Any generalities about a particular stock should be treated with caution because there are always exceptions to the rule. Nonetheless, the long and vast experience of beekeepers allows some oversimplifications to be made to better understand the different types of honey bees available. This publication provides a brief overview and comparison of some of the more common commercially available honey bee stocks in the United States (Table 1).

¹Disease resistance key: + = More inclined to have resistant qualities; - = Less inclined to be resistant or are more susceptible; 0 = Comparable susceptibility (neither better nor worse) ↲

*AFB = America foulbrood ↲

**EFB = European foulbrood ↲

Italian honey bees, of the subspecies Apis mellifera ligustica, were brought to the United States in 1859. They quickly became the favored honey bee stock in this country and remain so to this day. Known for their extended periods of brood rearing, Italian honey bees can build colony populations in the spring and maintain them for the entire summer. They are less defensive and less prone to disease than their German counterparts, and they are excellent honey producers. They also are very lightly colored, ranging from a light leather hue to an almost lemon yellow, a trait that is highly coveted by many beekeepers for its aesthetic appeal.

Despite their popularity, Italian honey bees have some drawbacks. First, because of their prolonged brood rearing, they may consume surplus honey in the hive if supers (removable upper sections where honey is stored) are not removed immediately after the honey flow stops. Second, they are notorious kleptoparasites and frequently rob the honey stores of weaker or dead neighboring colonies. This behavior may pose problems for beekeepers who work their colonies during times of nectar dearth, and it may cause the rapid spread of transmittable diseases among hives.

Honey bees are not native to the New World, although North America has about 4,000 native species of bees. Honey bees were brought to America in the seventeenth century by the early European settlers. These bees were most likely of the subspecies A. m. mellifera, otherwise known as the German or “black” honey bee. This stock is very dark in color and tends to be very defensive, making bee management more difficult. One of the German honey bee's more favorable characteristics is that it is a hardy strain, able to survive long, cold winters in northern climates. However, because of its defensive nature and susceptibility to many brood diseases (such as American and European foulbrood), this stock lost favor with beekeepers well over a century ago. Although the feral honey bee population in the United States was once dominated by this strain, newly introduced diseases have nearly wiped out most wild honey bee colonies, making the German honey bee a rare stock at this time.

A. m. carnica, from middle Europe, is a subspecies of the European honey bee and has been a favored honey bee stock in the United States for several reasons. First, explosive spring buildup enables this race to grow rapidly in population and take advantage of blooms that occur much earlier in the spring, compared to other stocks. Second, these bees are extremely docile and can be worked with little smoke and without protective clothing. Third, they are much less prone to robbing other colonies of honey, lowering disease transmission among colonies. Finally, they are very good builders of wax combs, which can be used in consumer products like candles, soaps, and cosmetics.

Because of their rapid buildup, however, carniolan honey bees tend to have a high propensity to swarm (their effort to relieve overcrowding), leaving the beekeeper with a very poor honey crop. This stock requires continued vigilance to prevent the loss of swarms.

A. m. caucasica is a race of honey bees native to the foothills of the Ural Mountains near the Caspian Sea in eastern Europe. This stock was once popular in the United States, but it has declined in regard over the past few decades. Its most notable characteristic is its very long tongue, which enables the bees to forage for nectar from flowers that other bee stocks may not have access to. They tend to be a moderately colored bee and, like the Carniolan honey bees, are extremely docile. However, their slow spring buildup keeps them from generating very large honey crops, and they tend to use an excessive amount of propolis—the sticky resin substance sometimes called “bee glue” that is used to seal cracks and joints of bee structures—making their hives difficult to manipulate.

In the 1920s, honey bee colonies in the British Isles were devastated by acarine disease, which now is suspected to have been the endoparasitic tracheal mite Acarapis woodi. Brother Adams, a monk at Buckfast Abbey in Devon, England, was charged with creating a honey bee stock that could withstand this deadly disease. He traveled the world interviewing beekeepers and learning about different bee strains, and he created a stock of honey bees, largely from the Italian race, that could thrive in the cold, wet conditions of the British Isles yet produce good honey crops and exhibit good housecleaning and grooming behavior to reduce the prevalence of disease. Bees of this stock are moderately defensive; however, if left unmanaged for one or two generations, they can be among the most fiercely defensive honey bees of any stock. They also are moderate in spring population buildup, preventing them from taking full advantage of early nectar flows.

One of the newer honey bee stocks in the United States was imported in 1997 from far-eastern Russia by the United States Department of Agriculture's (USDA) Honey Bee Breeding, Genetics, and Physiology Research Laboratory in Baton Rouge, Louisiana. The researchers’ reasoning was that these bees from the Primorsky Krai region on the Sea of Japan have coexisted for the last 150 years with the devastating ectoparasite Varroa destructor, a mite that is responsible for severe colony losses around the globe, and they might thrive in the United States. The USDA tested whether this stock had evolved resistance to varroa mite and found that it had. Numerous studies have shown that bees of this strain have fewer than half the number of mites found in standard commercial stocks. The quarantine phase of this project has been complete since 2000, and bees of this strain are available commercially.

Russian honey bees tend to rear brood only during times of nectar and pollen flows, so brood rearing and colony populations tend to fluctuate with the environment. They also exhibit good housecleaning behavior, resulting in resistance not only to the varroa mite but also to the tracheal mite.

Bees of this stock exhibit some unusual behaviors compared to other strains. For example, they tend to have queen cells present in their colonies almost all the time, whereas most other stocks rear queens only during times of swarming or queen replacement. Russian honey bees also perform better when not in the presence of other honey bee strains; research has shown that cross contamination from susceptible stocks can lessen the varroa mite resistance of these bees.

Several other honey bee stocks are worth noting:

The Minnesota Hygienic stock has been selected for its exceptional housecleaning ability, which significantly reduces the negative effects of most brood diseases.

The VSH, or the "varroa sensitive hygiene" stock (formerly called the SMR stock, referring to “suppression of mite reproduction”), also was developed by the USDA honey bee lab in Louisiana by artificially selecting commercial stocks for mite resistance. While not an independently viable stock on its own (because of inbreeding), the VSH trait has been incorporated into other genetic stocks so that these stocks may also express this highly desired characteristic.

The Cordovan honey bee is a type of Italian honey bee that has a very-light-yellow color, which is more attractive to many beekeepers.

Numerous hybrid stocks are also available commercially.

While a tremendous amount of variation remains within and among the different honey bee stocks, some generalities still can be made. Bee differences can be used to advantage by beekeepers, depending on what traits interest them, so using different stocks can be a powerful tool at the beekeeper’s disposal. There is no “best” strain of honey bee, as the traits favored by one beekeeper may differ significantly from another beekeeper's preference. Thus, it is best for each beekeeper to experience the characteristics of the different bee strains firsthand and then form an opinion about which stock best fits his or her situation.

For more information on beekeeping, visit NC State Extension's Beekeeping Notes website.