Beekeepers seek out resilient feral honey bees

When beekeeper Dwight Wells focuses on mites under a microscope, he likes to see body parts missing.

Parasitic varroa mites are a serious threat to Ohio’s honey bees, but some populations of feral honey bees defend themselves by chewing off the mites’ legs and eating into their abdomens, he explained.

Improvement project

That chewing behavior is one of the adaptations he’s looking for as part of the Ohio Queen Bee Improvement Project. Earlier this year, Wells and fellow beekeeper Zale Maxwell started the Ohio Queen Bee Improvement Project to selectively breed bees that are well adapted to Ohio conditions.

For several years, they’ve both been working with other beekeepers around the state to capture swarms of feral bees that are thriving without human help. Now they are hoping to use the superior genetics from those feral populations to develop more resilient captive bee colonies.

“We want to make beekeeping fun again,” Wells said.

Wells, who lives near Troy, Ohio, is retired from a career in engineering. Maxwell lives near Carroll and is also a retired engineer. They both started beekeeping well before Varroa mite infestations became a problem in the mid-1980s.

Wells got his start in 1954 for a 4-H project, and Maxwell started in 1964 to earn a beekeeping merit badge in the Boy Scouts. Beekeeping was simpler back then, Wells recalled.

Varroa mites and the diseases they carry have made it much more difficult to keep colonies going. “Beekeeping hasn’t been the same since,” he said.

Discouraging losses

Barbara Bloetscher, state apiarist with the Ohio Department of Agriculture, said Ohio beekeepers lose 30 to 40% of their colonies every winter. Varroa mites are a major cause of those losses. The colony losses and management challenges get to be too much for some beekeepers, Bloetscher added. She sees many new beekeepers giving up after about three years.

Mites weaken bee colonies by feeding on adult bees and bee larvae. To a bee, a mite is a big parasite, Bloetscher explained. “Comparatively it’s the size of a rat on us.”

The mite spreads diseases as well, she said. “While it’s weakening bees, it’s also injecting viruses.”

Controlling mites with miticides gets expensive, Bloetscher added. It’s also tricky because mites and bees are so closely related.

Identifying feral populations that defend themselves against the mites is a promising alternative, she said.

Feral advantages

Honey bees were first brought to North America in 1622 as a managed species. When bees escape from human management and form new colonies they are considered feral. Those colonies must either adapt to the local conditions or die out, Maxwell explained.

Honey bees have a short reproductive cycle and a high rate of genetic recombination, so swarms of feral bees are likely to come from well-adapted feral colonies that have grown too large, Maxwell said.

“These feral bees have already survived a winter in Ohio or the swarm wouldn’t have happened.”

To survive, feral bees develop a variety of traits that are also valuable in managed colonies, added Maxwell. The mite-chewing behavior is one of those traits.

Some feral populations also tend to work earlier in the morning and later in the evening than commercial stock, which is an advantage in honey production.

Maxwell and Wells have also identified some feral bees that defend their colonies from small hive beetles, another pest that kills bee larvae. They don’t know yet if the bees can kill the beetles, but, Maxwell said, “They’re harassing the bejesus out of them.”

Swarm trappers

Wells and Maxwell are building on feral bee research done by Greg Hunt at Purdue University, Tom Seeley at Cornell, and other researchers around the world.

After learning about their efforts, Wells started trapping swarms in 2012. He and Maxwell have enlisted a network of swarm trappers around the state.

“We’re to the point now we have a scientific approach to swarm trapping,” he said.

Some of the most promising genetic lines come from wooded areas along the Ohio River and its tributaries. They’ve also trapped well-adapted populations in Champaign County and Dayton’s inner city.

Feral bee colonies can be found in all parts of the state, but those in remote locations, isolated from managed bee colonies, are more likely to be well-adapted to Ohio conditions, Wells explained. That’s because they are less likely to have interbred with managed colonies brought in from other parts of the country.

Besides bringing better genetics to captive bee colonies, swarm trapping is a more economical way to get started in beekeeping, Wells pointed out. It’s still necessary to buy hives and protective gear, but the bees themselves are free.

He’s been working with a 14-year-old 4-H member who has built his own honey business by capturing 26 colonies of bees. As part of their bee improvement project, Maxwell and Wells are conducting beginning beekeeping and queen bee rearing classes at Maxwell’s farm. They’re especially interested in helping young beekeepers get started, Maxwell added.

Research goals

After capturing feral swarms, Wells and Maxwell are evaluating them for mite-chewing and other useful traits. For help with their research, they’ve enlisted Greg Stahl, a beekeeper from Champaign County.

Stahl is a retired Harvard professor with experience in cardiovascular research. He became interested in feral bees after taking up beekeeping as a retirement hobby. He saw an example of the resilience of feral bees when pesticides were sprayed on a neighboring farm, he said.

Many of the foraging bees from his commercial colonies died, but his captive feral swarm colonies showed few losses. The question, he said, is why the feral bees fared better.

More research is needed to determine if the feral colonies have better immune systems, if they have some way of knowing to avoid sprayed fields, or if there is some other reason for the advantage.

Stahl is using his research experience to design studies to look at the physical and behavioral differences between commercial and feral bees, he explained. “Where are the differences and how are the differences important?”

For instance, he’s looking at whether the mite-chewing behavior is related to mandible size on bees. Stahl is also looking at testing methods for bee diseases. Quick tests would help beekeepers identify and manage diseases without having to wait on lab results, he explained. “Ideally, I want something like a pregnancy test.”

Bee pedigrees

Another goal for the project is to develop a way of tracking bee genetics to get predictable outcomes, Wells said. Beekeepers in Germany have already established a certification program for queen bees, similar to livestock pedigrees. He’d like something similar here to help beekeepers select queens with the traits they want.

With more data, beekeepers can make better management decisions for their bee colonies, Wells said. “We have to become bee farmers. Everything in farming today is done by data.”