Selecting for Productivity and Quality

Breeding for productivity and product quality means improving honey, pollen, propolis or royal jelly yield, as well as traits such as winter consumption, rate of build-up and comb quality, by selecting on the basis of recorded measurements. Because yield is strongly affected by the environment, a single season's figure is misleading; several years of records and fair comparison are needed. Productivity can only be sustained with gentle, healthy colonies that overwinter well.

What determines a colony's productivity?

Besides genetics, honey yield depends on many environmental factors:

• The strength and duration of the forage and its distance from the hive
• Weather conditions and that year's nectar flow
• Whether the colony went into the main flow strong
• The age and laying capacity of the queen
• Varroa and disease pressure
• Whether it swarmed, and whether it was split
• When boxes were added and the beekeeper's other interventions

That is why the heritability of yield is low to moderate: most of the difference comes from the environment. A single season's yield figure does not give reliable information about a colony's genetics.

How is productivity measured?

• Harvested honey: Honey weighed per hive at every harvest. Honey frames left in the hive or moved to another hive are also recorded.
• Net weight gain: Weighing the hive at the start and end of the flow; this is a more reliable indicator than the amount harvested. Electronic hive scales also show daily nectar intake.
• Winter consumption: The difference between autumn and spring weights. A colony that consumes less is, in net terms, more productive over the year.
• Rate of build-up: The increase in the number of frames covered with bees and brood in spring.
• Brood density: The proportion of empty cells in the capped brood area; it shows the quality of the queen and the viability of the brood.

Winter consumption is often overlooked: a colony that makes a lot of honey and consumes a lot, and one that makes less and consumes little, may end up in the same place at the end of the year.

How do you compare productivity fairly?

Yield can only be compared if colonies are kept under the same conditions: the same apiary, the same hive type, similar starting strength and the same management. If you have different apiaries, compare not kilograms but the difference relative to the apiary average.

In kilograms, A produced more honey; but relative to its own apiary, B is superior. This relative value is the better guide when choosing breeders. Colonies that swarmed, went queenless or became diseased are not included in the yield comparison and are noted separately.

Why are overwintering and thrift part of productivity?

A colony that comes through winter strong on few stores is ready for the forage early in spring and lowers feeding costs. Some local races and ecotypes save stores by cutting back brood rearing when the flow stops; this thrift is especially valuable in regions with long winters or dry summers. In breeding, winter consumption and spring strength should be given as much weight as honey yield.

The risks of selecting on yield alone

When yield is made the only criterion, other traits quietly decline:

• Defensiveness can increase: Very hard-working but bad-tempered lines may come to the fore.
• Swarming tendency can rise: Colonies that grow very strong may also be prone to swarming.
• Winter consumption can increase: Lines that rear brood continuously use a lot of stores in winter.
• Disease resistance can weaken: If hygiene and mite resistance are not part of selection, they decline over time.

Breeding for pollen, propolis and royal jelly yield

There are also clear heritable differences between colonies in products other than honey:

• Pollen: The tendency to collect pollen is heritable; in research, high- and low-pollen-collecting lines have been separated by selection. It is measured by weighing the pollen collected with a pollen trap on set days.
• Propolis: Propolis collection differs between lines and races. The amount taken with a propolis screen is recorded.
• Royal jelly: Cell acceptance and the amount of jelly collected per cell are heritable. In China, lines selected over many years for royal jelly production have markedly increased yields.

Which traits are selected for product quality?

Productivity is not just quantity. Some differences between lines directly affect harvesting and processing time:

• Type of capping: Dry, white cappings or wet, dark cappings vary by race and even by line; this is very important for comb honey producers.
• Brood in the supers: The tendency of the queen to go up into the honey super differs between lines.
• Propolis and brace comb: Colonies that use little propolis and build little brace comb between frames make harvesting easier.
• Speed of comb building: Colonies that draw foundation quickly are valuable for comb honey and for splits.

How do you make a balanced selection?

The practical way is to create a simple total score that evaluates several traits together. The weights vary with the beekeeper's goals; for example:

The order of priority varies from beekeeper to beekeeper, but gentleness, overwintering and health often come before yield: high yield does not last long in an unhealthy, bad-tempered colony.