Beekeepers May Be Throwing Away the Thing That Could Keep Bees Healthy

Beekeeping isn’t for the faint of heart. Honey bees battle a constant onslaught of threats, from pesticide-resistant Varroa mites to habitat loss and chemical exposure. Any one of these challenges can spell disaster for a hive. Fortunately, there is a lot of research being done to develop methods that are not only good for the bees, but good for the beekeepers, too!

A Waste Product Turned Superfood

A study published in December in the Journal of Economic Entomology examines the nutritional value of a novel pollen supplement made from larval male bees, or drone brood.

Supplemental macronutrients are often essential to keep honey bee hives thriving during winter, droughts, or times when nectar and pollen are scarce. Carbohydrates are supplied through excess honey or syrup mixtures, and pollen patties can provide proteins and fats for the colony. However, pollen patties can be expensive and may not always provide the right micronutrients honey bees need to stay healthy.

Researchers at the University of Belgrade studied how a common beekeeping waste product could impact honey bee health. Drones—male bees that are necessary to fertilize the queen but which do not produce honey—are typically culled from colonies because they sap resources. They only reproduce with virgin queens in nuptial flights, and when they begin leaving the hive, they consume a portion of the honey reserves. Drones are also more susceptible to Varroa mites. Thus, removing a portion of drone brood cells can improve the health of the colony and is a common practice among beekeepers in spring or early summer. The University of Belgrade researchers decided to use this drone brood to create a flour that can then be used as a pollen substitute in feeding the rest of the hive.

In honey bee hives, drone brood is often discarded because the male bees sap resources. Drones are also more susceptible to Varroa mites. Thus, removing a portion of drone brood cells can improve the health of the colony and is a common practice among beekeepers in spring or early summer. A new study suggests drone brood, rather than going to waste, can be recycled into flour patties rich with protein, fats, and essential minerals that can be fed back to the rest of the hive as a pollen substitute. (Photo courtesy of Ratko Pavlović)

Bees Already Eat Their Own Brood, So Why Not Feed It to Them?

Ratko Pavlović, a professional beekeeper and Ph.D. candidate, addresses the concern that some may have with bees eating their own brood. “It’s a documented behavior that honey bees will eat drone larvae when pollen sources are low, but not very many beekeepers know about it,” he says. “When honey bees are lacking some nutrients or there is a long period of rain and bees can’t forage, they will eat their own brood. It’s a very common, everyday behavior. For example, if there are multiple eggs or larvae in one cell, the bees will consume them to ensure there is only one per cell.”

This behavior sparked Pavlović’s curiosity: If bees already eat drone brood, could processed drone larvae serve as a viable pollen substitute? The answer, it turns out, is promising.

His research found that drone brood flour is a rich source of protein, fats, and essential minerals that honey bees need to stay healthy.

How Beekeepers Can Make Their Own Drone Brood Flour

Pavlović developed a simple method that any beekeeper could follow to create this nutrient-dense, free supplement. All you need is a pot for boiling and a strainer. Removing capped drone brood is a standard procedure for many beekeepers, but capped drone brood is usually discarded because the efforts to extract wax are too costly.

The procedure includes boiling the capped drone brood twice, straining the brood out each time and extracting the wax. The drone brood can then be processed into a type of flour. So, from a typical beekeeping waste product, a beekeeper can get pure wax and a pollen substitute.

“It’s a simple process that can be combined with a sugar patty to keep your bees healthy. I know many beekeepers who do a lot more complicated things. This is quite simple,” Pavlović says.

A Natural Solution for the Varroa Mite Problem

Additionally, research has shown that this practice of removing drone brood can improve honey yields and reduce Varroa mite populations in a hive. Varroa mites originally evolved to parasitize Apis cerana, the honey bee species native to Asia, and only affected drones of that species. When Varroa mites infect worker brood in Asian bees, the larva dies and the Varroa mite can’t reproduce.

As they adapted to the honey bees (Apis mellifera) common in Europe and North America, however, Varroa mites became able to parasitize drone, queen, or worker bees. However, there is a still a large preference for drone brood. Varroa mites are often 5–10 times more abundant in drone brood cells than worker or queen cells. Since drones take longer to mature into adults and the drone brood are bigger, the Varroa mites can produce more offspring in these cells. By removing excess drone brood, a beekeeper can eliminate a large portion of their Varroa mite population.

“There can easily be 1,000 to 2,000 drone cells in a hive. Not only will they be full of Varroa mites, but the drones will eat honey when they go on their nuptial flights,” Pavlović says. “If you remove drone brood, they won’t be using up the honey supplies. By removing them from colonies with unwanted traits, you can select for better disease resistance, healthier queens, or whatever traits you want. This can have lots of benefits for the beekeeper.”

How Drone Brood Might Boost Bee Immunity

While drone brood flour can provide the protein and fats for honey bee nutrition, it may also play a role in reducing diseases in a hive. Nenad Zarić, Ph.D., senior author on the study, suggests that overlooked micronutrients are an important aspect of honey bee health that needs more attention. “There is evidence that certain diseases can be prevented with proper nutrition,” Zarić says. “For example, studies have shown that chalkbrood disease mummies are much lower in silver compared to healthy bees. We found that silver was very high in drone brood, so there is some hope that feeding drone brood to honey bees could possibly have some antimicrobial effects on the bees.”

This could mean that drone brood supplementation could do more than just replace expensive pollen patties. It might actively support bee immune health by providing key trace elements that help fight off infections.

A Win-Win for Beekeepers and Bees

Despite the scientific evidence, many beekeepers hesitate at the thought of bees eating their own brood, believing it could lead to the spread of disease. However, this is a misunderstanding of how honey bee colonies function as a hive.

“I would love to have beekeepers become more aware of this interesting habit in bees,” Pavlović says. “Most beekeepers will say that bees don’t cannibalize their brood and that this would result in more diseases. But this isn’t true. You have to think of the bees as a superorganism, and this natural process of culling larva or eggs is healthy for them.”

This natural behavior helps colonies conserve resources, regulate brood numbers, and optimize their health. By understanding and harnessing this process, beekeepers can turn what was once a waste product into a valuable tool for sustainable hive management.