“Keeping wild animals is a great way to show that we have a connection to nature,” said the general manager, Adrijana Hauptman Vidergar. “And we’ve had great feedback from guests who go up there and take a look.”

The hives are managed by Gorazd Trusnovec, a 50-year-old with a graying goatee who is the founder and sole employee of an enterprise called Najemi Panj, which translates to “rent-a-hive.” For a yearly fee, he will install a honey bee colony on the roof of an office, or in a backyard, and ensure that its Bees are healthy and productive. Customers get the honey and the pleasure of doing something that benefits bees and nourishes the environment.

That, at any rate, was Mr. Trusnovec’s original sales pitch. In recent years, he and other beekeepers, as well as a broad variety of leading conservationists, have come to a very different conclusion: The craze for Honey Bees now presents a genuine ecological challenge. Not just in Slovenia, but around the world.

“If you overcrowd any space with honey bees, there is a competition for natural resources, and since bees have the largest numbers, they push out other pollinators, which actually harms biodiversity,” he said, after a recent visit to the B&B bees. “I would say that the best thing you could do for honey bees right now is not take up beekeeping.”

It’s like Johnny Appleseed announcing, “Enough with the apples.” That’s a jarring message, and not just because honey bees play a crucial role in the food chain, pollinating about one-third of the food consumed by Americans, according to the Food and Drug Administration. It’s also because there is a widespread and now deeply rooted belief that the global population of honey bees has been running dangerously low for more than a decade.

The notion has spurred a boom in beekeeping, most notably among corporations eager to demonstrate their green bona fides.

But the urge to acquire a hive comes from the simplification of some complicated facts, says Scott Hoffman Black, executive director of the Xerces Society for Invertebrate Conservation in Portland, Ore.

A malady originally dubbed disappearing disease had been afflicting honey bees for decades. In the fall of 2006, an American beekeeper named Dave Hackenberg checked on his 400 hives and found that in many, most of the worker bees had disappeared. Other beekeepers started to report that they were losing upward of 90 percent of their colonies. The phenomenon was renamed colony collapse disorder. The cause remains unclear, but experts tend to blame pesticides, an invasive parasite, a reduction in forageable habitat and climate change. An alarm was sounded, and “save the bees” became a rallying cry.

“It was the first time that a large number of people started talking about pollinators, which was great,” Mr. Black said. “The downside was that there was no nuance. All anyone heard was that bees were declining, and so I should get a hive.”

Honey bees, it turns out, are a commercially managed animal — essentially livestock, like cows — and large beekeeping operations are remarkably adept at replacing colonies that die. In the United States, about one million hives are trucked each year to places like California, where honey bees pollinate almonds and other crops, Mr. Black said. It’s a major industry. Revenue from beekeeping will reach $624 billion this year in the United States alone, reports IBISWorld, a market research firm.

While techniques for nurturing hives have improved, honey bees remain vulnerable animals. As of a few years ago, nearly 30 percent of commercial honey bees still did not survive the winter months, says the Environmental Protection Agency. That’s a large number and one that puts a financial strain on commercial beekeepers.

“But that’s an agriculture story, not a conservation story,” Mr. Black said. “There are now more honey bees on the planet than there have ever been in human history.”

Figures from the Food and Agriculture Organization of the United Nations underscore the point. The number of beehives around the world has risen by 21 percent in the last decade, to 102 million from 81 million.

Still, the save-the-bees narrative persists. Its longevity stems from confusion about what kind of bees actually need to be rescued. There are more than 20,000 species of wild bees in the world, and many people don’t realize they exist. That’s because they don’t produce honey and live all but invisibly, in ground nests and cavities like hollow tree trunks. But they are indispensable pollinators of plants, flowers and crops.

Researchers have found that many species of wild bees are, in fact, declining. So trying to save them makes eminent sense. But hobbyists and corporations, not to mention luminaries like Beyoncé and Queen Camilla, are drawn only to the seven or so species of honey bees — the one group supported by a multibillion-dollar agribusiness and that doesn’t need the help.

Hives are now getting installed at what beekeeping association leaders say is a record pace. As with the B&B Hotel, they are typically motivated by an impulse to do something positive for the environment that is also highly visible — an apiary form of greenwashing. (Hivewashing?)

Recently, the Museum of Modern Art posted an image of four hives on its Instagram account, along with text that read, “We recognize the essential part bees play in our ecosystem and that’s why we are proud to provide a home to all these bees here at the Museum.” In London, the sheer quantity of hives poses a threat to other species of bees, says a report issued in 2020 by the Royal Botanical Gardens, Kew. The city’s financial district is now overrun with what Richard Glassborow, the chair of the London Beekeepers’ Association, calls “trophy bees.”

“We’ve had companies from outside London come with plans to put 20 hives a year on roofs,” he said, “and persuade businesses that this will tick some kind of corporate responsibility box.”

New York City has a similar problem, says Andrew Coté, president of the New York City Beekeepers Association. In February, MoMA asked him to install the hives it recently showed off. He declined.

“The population is already overwhelming the finite floral resources,” he said. “We don’t need more honey bees here.”

People like Mr. Coté are in a peculiar spot. They lead a membership of honey bee enthusiasts in a place with too many honey bees. There are no regulatory limits on hives, so the law is no help. In London, all Mr. Glassborow can do is explain to current and prospective members that the last thing the city needs is more hives.

It usually works. Companies that confer with him often end up planting flowers, which increases the food supply for many pollinators. But most companies and hobbyists don’t call for a chat. With the number of hives rising, pressure is mounting on less charismatic insects, like moths, wasps and wild bees, which are essential to pollinating wild plants and many crops, and which academic studies have found are in decline. Apparently nobody wants 25,000 moths parked near the C-suites.

Today, hives are so ubiquitous in some places, especially urban areas, that the amount of honey each yields is dropping. Slovenia now produces less honey than it did 15 years ago, according to government figures, even though it has more than doubled the number of hives in the country. That’s because there is not enough nectar to go around, said Matjaz Levicar, a Slovenian beekeeping instructor, and honey bees are consuming it to survive rather than turning it into honey.

“It’s a tragedy,” he said. “In Slovenia, we need to feed honey bee colonies with sugar most of the year.”

Asking people to dial down their honey bee enthusiasm isn’t easy. They are the celebrities of the insect world, a source of fascination, for their uncannily efficient social structure, and referenced in nearly every world religion.

“Honey was seen as a gift from the gods,” said Sarah Wyndham Lewis, author of The Wild Bee Handbook. “Honey bees gave humans food, medicine and a trade which enabled people to improve their lives. It might have been the first source of alcohol, too, which let people go off their heads.”

Nowhere is honey more deeply ingrained in national culture than Slovenia, where beekeeping has been a national passion for generations. It is so deeply ingrained here that last year UNESCO called it “a way of life” and added it to the Representative List of Intangible Cultural Heritage of Humanity, the same list that enshrines France’s connection to the baguette.

That history might explain why it took Mr. Trusnovec, the rent-a-hive beekeeper, a few years to realize that honey bees don’t need to be rescued. He came to beekeeping as a hobbyist in his mid-30s, when he earned a living as an architectural engineer and as a film critic. Both jobs left him staring at screens all day, and he pined for less sedentary work.

Then, one day about 15 years ago, he had a powerful memory of his grandparents’ idyllic house near Slovenia’s border with Italy, which was surrounded by a creek, acacia trees and beehives kept by an uncle.

“It’s a very Proustian story,” he said. “All of a sudden I remembered this smell, not quite honey but bees and pollen, a very complex and beautiful smell. I thought to myself, I must get in touch with bees somehow.”

He learned beekeeping from books, and started with two hives on his balcony. To his delight, he quickly realized he had an aptitude for the work — “the bees didn’t die,” as he put it dryly — and he had found a way to connect with nature while remaining in the city.

His first hive-renting client was a cultural center focused on dance. Other customers came calling — schools, corporations, hotels, banks, private citizens. One of his clients is the Petrol Group, Slovenia’s largest energy company.

Mr. Trusnovec plans to reduce the number of hives he keeps to 40 from 50, and perhaps an even lower number soon enough. To reach that goal, he is having delicate conversations with clients about the evolution of his thinking and the realities of the bee population. That it’s time to assist thousands of bee species that actually need help and end the love affair with honey bees, which don’t.

“It’s difficult,” he said. “If someone were to call me today, I would advise them to put up a hotel for solitary bees or boxes for bumblebees. Or plant some trees instead.”