Honeybees are solar creatures, and as such they like to stay warm all year.
Australia has about 1,800 commercial beekeepers and 28,000 hobby beekeepers.
New research from Australia’s Queensland University of Technology (QUT) reveals the amount of work it takes honeybees to keep their beehives at 35C (95F) all year round. It also indicates how changes to hive design and better beekeeping practices can save bees time and energy.
With all the advances in technology and building efficiency, it defies logic that the most common commercial beehive still in use today in places like the United States, Australia and New Zealand is a timber box system designed in the 1850s that is far from thermally efficient.
PhD researcher Dan Cook from the QUT Design Lab and the Centre for Agriculture and the Bioeconomy, has been doing “bee-centric” postgraduate research for the past three years to investigate how bees experience the honey and pollination industries, and how humans can help bees to maximize the time they spend doing essential work.
As an amateur beekeeper, Mr. Cook has found that honeybees must spend up to 80,000 ‘bee-minutes’ warming a hive back up to its ideal 35C (95F) after beekeepers disturb its micro-climate.
As a QUT industrial design graduate, he says improvements to hive design, like more insulation and better sealed lids, can help reduce the time and energy expended. Picking warmer days to open the hives would help as well.
He states that beekeeping hasn’t changed much in 170 years, although most agriculture industries have evolved over time. Hive experiments in QUT labs showed that Langstroth hives are thermally inefficient. They also highlighted how much energy bees must expend to keep the inside of the hive at their optimal 35C (95F) temperature.
Mr. Cook says honey provides thermal mass in the beehive, and is a thermal buffer to external temperature change. Removing honey on a cool rainy or windy day means bees must work extra-hard as ‘heater bees’ – vibrating wing muscles to raise body temperature and warm the brood. This takes worker bees away from foraging for food and water.
This research was published in the Journal of Economic Entomology, in the article called: Thermal Impacts of Apicultural Practice and Products on the Honey Bee Colony.
In this unrelated 5:34-minute video, Greg Melikhov shows how he keeps his hives warm in winter:
The authors coined the phrase “bee-minutes” as a new way to measure bee energy expenditure, so the industry can see how much time certain tasks take, like hive micro-climate regulation. Bee-minutes represent the number of minutes it takes a bee to do heating work.
A task can take 100 bees one minute, or one bee 100 minutes, so 100 ‘bee-minutes’ is an easy and accurate way to express this time.
Recommendations Mr. Cook makes in his research include thermal improvements to the hive like more insulation and better sealed lids, an ergonomic improvement to help beekeepers’ backs, and ways to pay more attention to and work better with the weather.
Further, he says handles would be a great addition to beehives, since hives only have finger holds cut out, and hives are up to 35 kg (77 lbs) so lifting them is a challenge.
Only 9 frames fit comfortably in the traditional ’10-frame’ Langstroth hive. The tenth frame makes it too tight and increases the risk of squashing bees, including the queen.
Wood lasts longer, so commercial beekeepers tend to prefer it to polystyrene hives which are more thermally efficient.
The beekeeping industry will not change overnight but there are two easy ways beekeepers can make life easier for their bees. First, replace their ‘standard’ lids with a thicker lid that seals better and gives more insulation. Second, work on hives on the warmest day possible.
Adding comb frames is known as supering. This makes a lot of extra work for bees to warm the expanded hive, especially if it is a cold day, or the comb is cool from refrigeration or transport. Adding the super on a warm day can save the bee colony up to 3 times the heating energy.
Mr. Cook’s research is ongoing at the new QUT Research Apiary, and the QUT Samford Ecological Research Facility north-west of Brisbane, Australia, and is funded by Hort Innovation.