American bee colonies have suffered record losses over the past two years

American beekeepers lost nearly half of their hives in the 2022 growing season.

That’s just a bit lower than the previous highest loss on record — which occurred the previous year, according to a report published Thursday.

Both years represented an unusually high fatality rate even for the embattled honeybee, a critical pollinator whose keepers have for decades faced a heartbreaking and protracted sustainability crisis.

Thursday’s report was born out of that crisis.

Since 2006, the bee labs at the Alabama-based University of Auburn and the University of Maryland have tracked rates of “colony collapse disorder,” or when a hive fails entirely.

That timing was no accident: The disorder first appeared in 2006, when a rash of beekeepers began to describe a surreal occurrence in which adult worker bees deserted a hive, leaving the queen and her larvae behind.

While the keepers typically found few dead bees around the hives, the absence of the workers amounts to a delayed death sentence for the colony: Without the queen, the exiled hive of sterile drones would have no way to build a new nest.

That represented an immediate and serious problem for U.S. agriculture, which relies on nectar-seeking bees to transport pollen from one flower to another on its fuzzy face and legs — fertilizing plants and allowing fruits to grow.

Bees — both wild native ones and introduced domestics like honeybees — pollinate more than 80 percent of America’s flowering plants, according to the Department of Agriculture.

A die-off of beneficial insects like bees would mean “a real food production problem,” Melissa Perry, who chairs an environmental health department at George Washington University, said in a 2019 explainer.

“It’s impossible to replace what we call the ‘ecosystem services’ of the insects and how they are pollinating the plants that we rely on for food,” Perry added.

For approximately the last decade, hives have continued to fail over the winter at rates nearly double what beekeepers consider acceptable.

During that period, the average winter rate of collapse has been nearly 40 percent; the acceptable winter loss rate is about 20 percent.

In 2022, 60 percent of beekeepers lost an unsustainable number of colonies.

“This is a very troubling loss number when we barely manage sufficient colonies to meet pollination demands in the U.S.,” former government scientist Jeff Pettis told The Associated Press.

“It also highlights the hard work that beekeepers must do to rebuild their colony numbers each year,” added Pettis, who is now president of the global beekeeper association Apimondia and was not part of the study.

It’s easy to forget when watching honeybees buzz among flowers that they are no more native to this continent than the Europeans who brought them. 

In Thomas Jefferson’s “Notes on the State of Virginia,” for example, he suggests the buzzing of bees might have taken on ominous sound for North America’s original inhabitants.

Honeybees “have generally extended themselves into the country, a little in advance of the white settlers,” Jefferson wrote.

“The Indians therefore call them the white man’s fly, and consider their approach as indicating the approach of the settlements of the whites.”

From that tenuous 18th century foothold, honeybees expanded to a late 1980s peak of 3.5 million colonies — before beginning a period of protracted (if occasionally interrupted) decline to their current population level of about 2.7 million.

Keeping levels from falling further represents a full-time headache for the nation’s hundred thousand-plus beekeepers.

This year, like most years, saw beekeepers in a continuous race to keep up with the growing threats to their bees.

And also like most years, the leading threat this year was the aptly named — and increasingly lethal — Varroa destructor mite, a small arachnid that crawls over bees and transmits viruses that kill them.

While killing a colony once required its being nearly two-thirds infested with Varroa mites, the viruses are much more lethal now, and a colony with just 2 percent infestation is now liable to fail, the AP noted.

But climatic factors were right behind the Varroa in causing failures of bee operations, from backyard to commercial: Growers of all sizes cited “adverse weather” as being a primary cause in their colonies’ failure.

That can mean unusual rain, drought, heat or cold. But there is also substantial evidence that as the climate changes, bee populations are drifting out of sync with many of the flowers they pollinate, with serious impacts for both bees and flowers.

Bees can also suffer if the crops they depend on fail due to heat stress, according to a 2020 study in Veterinary Science.

Backyard beekeepers told the surveyors that “starvation” followed Varroa infestations and adverse weather as a principal cause of colony failure.

One strange quirk of bee co-living arrangements brings these two risks together. 

Bees provide the main form of heating and air conditioning for the colony — crunching their muscles together and gathering in big, vibrating comps to warm a cold hive, or beating their wings in unison to cool a hot or humid one, as the University of Georgia has reported.

But running this natural heating and air conditioning requires the bees to “have sufficient access to carbohydrates [nectar, in this case] to maintain these temperatures and survive.”

With the natural cycles that control temperature, food and the life cycles of bees in many regions drifting out of whack, there are more points at which a complex system like a colony can fail.

Speaking to the AP, representatives of the federal government suggested the future of bees would be rocky.

“There are threats certainly in the environment and honeybees have persisted,” U.S. Department of Agriculture research entomologist Jay Evans said.

“I don’t think honeybees will go extinct but I think they will always have these sort of challenges.”