The Bee Year

A colony's life follows the year: slow in winter, then a surge in spring, a peak in summer and a wind-down in autumn. Beekeeping Fundamentals 2 described the colony and Beekeeping Fundamentals 4 described the hive's own temperature. This chapter joins those into a year, using what two sources say about seasons and about the temperatures bees can work in. It is honest about a limit: the sources describe the bees' year, not a month-by-month list of beekeeper jobs, so inspection schedules and record-keeping are covered only where the sources say something.

The Colony's Year

Wikipedia's Western honey bee article says that in temperate climates the bees gather in the hive and wait out the cold season, when the queen may stop laying and activity is slow. The colony then lives on its stored honey, which is also used to make metabolic heat. In mid to late winter the queen starts laying again, probably triggered by day length. In spring and early summer, with flowers abundant, the colony may swarm. Through the rest of the growing season it produces many workers who bring in pollen and nectar as food for the cold season, and in midsummer a healthy hive's population may reach 40,000 to 80,000 bees.

Temperature: What Bees Can and Cannot Do

The same article gives a set of temperature thresholds. A bee needs an internal body temperature of 35 °C (95 °F) to fly, and the nest is kept at that temperature to develop the brood; it is also optimal for making wax. The winter cluster's internal temperature may be as low as 20 to 22 °C (68 to 72 °F), and the cluster's outside edge varies with the air temperature.

Checking the conversions

I converted the Celsius figures myself with F = C × 9/5 + 32 and ran the calculation in Python. Most agree with the article's Fahrenheit values after rounding: 7 °C is 44.6 °F (the article says 45), 10 °C is 50.0, 20 °C is 68.0, 22 °C is 71.6 (72), 25 °C is 77.0, 35 °C is 95.0, 38 °C is 100.4 (100) and 50 °C is 122.0.

The Mechanisms Behind the Numbers

The article says bees forage over that wide range thanks to behavioural and physiological regulation of their flight muscles. From cold to hot, it lists: shivering before flight and pausing flight to shiver more; passive body temperature regulation based on the work being done; and evaporative cooling from regurgitated honey-sac contents. In hot conditions a bee dissipates heat from the thorax through the head, producing a "honeycrop droplet" that lowers the head temperature by 10 °C (18 °F).

What the Source Does Not Give

The sources I read describe what bees do through the year. They do not give a calendar of beekeeper tasks, how often to inspect, how to keep records, or what to do in each month. Beekeeping Fundamentals 3 mentioned that conventional advice often says to inspect weekly in warmer months, but that was a passing remark in the source, and it is not a recommendation here.

Not Yet Verified, and Sources

• Source. Everything attributed to "the article" comes from the plain-text version of Wikipedia's Western honey bee article (about 54,500 characters). This chapter uses its colony life-cycle, queen and thermoregulation sections, which I read in full. A passing reference to inspection frequency comes from the Beekeeping article used in earlier chapters. Other sections of both articles were not read for this chapter.
• Conflict or error. The "30 °C (86 °F) range" is probably a conversion mistake in the source (explained above).
• Not in the sources. Seasonal task lists, inspection frequency, record keeping, and the form of the observation record above (my suggestion). Also behaviour outside temperate climates (check).
• Code. A short Python calculation converted the temperatures; every value matches the page.

Exercises