The New World Carniolan is selected to be highly productive, gentle and winter hardy. They are also selected for traditional A.m. carnica characteristics. Well tuned to the environment; spring buildup is rapid and brood production shuts down when resources are scarce. Swarming is not a problem as we have selected against this trait.

INDUSTRY
Colonies are selected for productivity. During the honey flow a weight gain test is used to evaluate and select breeder colonies for honey production. The bees tend to work longer hours and actively forage when conditions are marginal Excluders are rarely needed, as the NWC is efficiently organized and maintains a tight brood nest, characteristic of the Carniolan race.

Joe Latshaw, a student at OSU pulling honey from instrumentally inseminated NWC breeder colonies.

RAPID SPRING BUILDUP
Overwintered Breeder colonies are selected for early spring buildup. This has increased the population growth rate and productivity of colonies. The first available pollen is a key stimulus, as the NWC responds quickly to environmental cues.

OVERWINTERING ABILITY
The Ohio winter provides an opportunity to evaluate overwintering ability. Breeder colonies are not wrapped and not treated for tracheal mites. These are selected for good wintering and efficient use of winter stores.

Carniolans traditionally have smaller winter clusters, compared to Italian bees. We are selecting for larger winter clusters in the NWC. This trait combined with their dramatic spring buildup and ability to forage when conditions are marginal, produce populous colonies early in the season.

REDUCED SUSCEPTIBILITY TO TRACHEAL MITES
Tracheal mite resistance appears to be a highly heritable trait. Selection for high performance and good overwintering ability coupled with controlled mating has greatly reduced susceptibility of the NWC to tracheal mites.

The breeding population of NWC at OSU has never been treated for tracheal mites. We took our major losses in 1990 and 1991 when mite levels approached 50%. Infestation levels have consistently and dramatically decreased annually to almost undetectable levels since 1994 without treatment. Early spring mite loads of untreated, overwintered colonies have remained low, averaging between 2% and 3% from 1994 to 1998. In 1999 levels averaged 7%, a slight increase, though a noticeable reduction in performance was not detected.

We are continuing to monitor mite levels and to select for colony performance to ensure these traits are maintained. Without identifying the mechanisms of defense against tracheal mites, simply selecting for high productivity has proven to be a practical and effective selection method. We will continue rigorous selection and monitoring of mite levels.

HYGIENIC BEHAVIOR
Hygienic behavior is a specific trait we have added to our selection criteria. A freeze killed brood assay is used to evaluate the ability of bees to uncap and remove dead brood. This behavior has been shown to reduce the incidence of brood diseases and reduce Varroa infestations. It is a recessive trait that is commonly found in about 10% of honey bee populations.

Within the NWC breeding population we are selecting to increase the frequency of hygienic behavior and plan to establish this as a common trait. At present you will find hygienic behavior is variable in our stock. This is because our primary criteria remains selection for overall high performance using a holistic approach, which slows the selection process for a specific trait.

Colony productivity is dependent upon a variety of characteristics which can be lost when selection is too limited. Colonies that test hygienic must also be selected for productivity. We are working to increase this trait in our gene pool.

Liquid nitrogen is used to perform the frozen brood assay to determine hygienic behavior.

POLLEN COLLECTION
Selection for high pollen collection helps promote healthy, vigorous colonies and aids in pollination efficiency. We select for the characteristic rainbow of pollen surrounding the brood. Because the NWC tends to work longer hours and when weather conditions are cool and drizzly, this also benefits pollination services.

GENTLE TEMPERAMENT
The Carniolan is known for its calm and gentle temperament. We select for this, at all stages of colony size. This poses less problem for agricultural workers and locating colonies in populated areas. Plus, beekeeping is more enjoyable.

HIGH BROOD VIABILITY
A large gene pool is maintained, as this is essential to persevere the integrity of the breeding population of the NWC. Solid brood patterns are selected to avoid problems of inbreeding.

Occasionally, we introduce new stocks after careful and extensive testing. This is accomplished slowly and with caution to avoid any dramatic or unforeseen change in the population. The NWC population is closed to the introduction of untested and unknown stocks through the use of instrumental insemination.