Managed honey bee colonies have grown in total number worldwide over the past several decades, but wild bee populations tell a very different and more troubling story. Between 1961 and 2017, the global count of managed honey bee colonies rose by about 85%, and honey production nearly tripled.1Nature. Uptrend in global managed honey bee colonies and production based on a six-decade viewpoint, 1961–2017 Meanwhile, roughly a third of assessed bumblebee species are in decline, and many solitary wild bee species face habitat loss, pesticide exposure, and climate disruption with little monitoring to track what is happening to them.2PubMed Central. Global decline of bumblebees is phylogenetically structured and inversely related to species range size and pathogen incidence Whether bees are “coming back” depends entirely on which bees you are asking about, and the answer reveals how misleading it can be to treat all bees as one group.
Managed Honey Bees Are Growing in Number, but Context Matters
The headline numbers on honey bees look surprisingly optimistic. Over the six decades from 1961 to 2017, the world added colonies at an 85% clip, honey production climbed by 181%, and each colony became about 45% more productive on average.1Nature. Uptrend in global managed honey bee colonies and production based on a six-decade viewpoint, 1961–2017 Those gains were concentrated in Asia, Africa, and South America, where commercial beekeeping expanded rapidly. Europe and North America, by contrast, saw stagnation or outright losses in colony numbers during the same period.
Even the global picture comes with a catch. Human population grew by 144% over the same timeframe, so the number of colonies per person actually fell by about 20%, from roughly 14 per thousand people to about 11.1Nature. Uptrend in global managed honey bee colonies and production based on a six-decade viewpoint, 1961–2017 In practical terms, the world’s demand for pollination services has been rising faster than the supply of managed bees to meet it. And the growth in colony counts masks the fact that beekeepers have been working harder just to stay even, replacing dead colonies each spring to maintain their totals. The raw number of hives in existence is a poor proxy for hive health.
Wild Bees Are a Different Story
Wild bees, including the 250-odd bumblebee species and thousands of solitary bee species, do not get restocked by beekeepers each year. When their populations drop, recovery depends on habitat, food, and freedom from the pressures driving them down in the first place. Globally, about one-third of assessed bumblebee species are declining, and those with smaller geographic ranges are particularly vulnerable.2PubMed Central. Global decline of bumblebees is phylogenetically structured and inversely related to species range size and pathogen incidence The declines are not random across the family tree; they cluster in certain evolutionary lineages, suggesting that traits shared among related species may predispose them to decline.
Future projections for some regions are bleak. In East Asia, modeling of 29 endemic bumblebee species under future climate and land-cover scenarios found that 59 to 93% of those species could lose range by mid-century, and several were predicted to reach critically endangered or endangered status.3Agriculture, Ecosystems & Environment. Vulnerability of East Asian bumblebee species to future climate and land cover changes These are species that cannot simply be trucked to a new location like managed hives. Their fate depends on whether suitable habitat exists where they need it and whether they can shift their ranges fast enough to keep up with changing conditions.
The Varroa Mite and Its Viral Cargo
For managed honey bees, the single biggest biological threat is Varroa destructor, a parasitic mite that feeds on developing bee pupae and adults. The mite’s direct damage is bad enough, but its real destructive power lies in the viruses it transmits, especially deformed wing virus (DWV). DWV is now considered a global epidemic in honey bees, driven by the direct transmission route that Varroa provides.4PubMed. Deformed wing virus is a recent global epidemic in honeybees driven by Varroa mites Infected pupae can die outright or emerge with crumpled wings, shortened abdomens, and cognitive problems that leave them unable to function normally in the colony.5PubMed Central. Direct Evidence for Infection of Varroa destructor Mites with the Bee-Pathogenic Deformed Wing Virus Variant B – but Not Variant A – via Fluorescence-in situ-Hybridization Analysis
For years, scientists debated whether the mite was merely a mechanical carrier of the virus or whether DWV actually infected mite cells and replicated inside them. Recent work has found direct evidence that one variant of the virus, DWV-B, does infect the mite’s gut lining and salivary glands, making it a true biological host for that strain.5PubMed Central. Direct Evidence for Infection of Varroa destructor Mites with the Bee-Pathogenic Deformed Wing Virus Variant B – but Not Variant A – via Fluorescence-in situ-Hybridization Analysis This distinction matters because a virus that replicates inside its vector is harder to control: the mite becomes an active amplifier, not just a dirty needle. Managing Varroa remains the front line of keeping honey bee colonies alive through winter, and most commercial beekeepers in the U.S. and Europe treat colonies with miticides at least once a year.
Neonicotinoids and the Sublethal Problem
Pesticides rarely kill bees outright at the doses they encounter in the field. The more insidious problem is sublethal exposure, particularly to neonicotinoid insecticides, which target the same nerve receptors in bees that they target in crop pests. At low doses, these chemicals impair navigation, shorten lifespans, suppress immune function, and disrupt the ability of workers to care for brood and regulate hive temperature.6PubMed Central. The Sublethal Effects of Neonicotinoids on Honeybees A forager that cannot find its way home is effectively dead to the colony even if the chemical did not technically kill it.
Recent work has refined the picture of how this plays out. When forager bees were exposed to the neonicotinoid imidacloprid, their return rate dropped significantly. The underlying cause did not appear to be a direct failure of navigation-related brain function; instead, the bees showed signs of disrupted energy metabolism and hormonal imbalance, as if they lacked the fuel and physiological coordination needed to make the trip home.7PubMed. Sub-lethal neonicotinoid exposure impairs homing ability in honey bee (Apis mellifera) foragers via the disruption of energy metabolism and endocrine regulation rather than cognitive ability These sublethal effects compound each other and interact with other stressors like Varroa mites and poor nutrition, making it difficult to isolate any single cause of colony failure.
The European Union imposed a partial ban on three neonicotinoids for outdoor use starting in 2013. Some researchers have argued that evaluating the ban’s effects on bee health was premature given the timeline involved and the difficulty of disentangling neonicotinoid impacts from other ongoing pressures.8PubMed Central. Three years of banning neonicotinoid insecticides based on sub-lethal effects: can we expect to see effects on bees? The debate around whether these bans will translate into measurable bee recovery is ongoing, and the science is genuinely unsettled.
Climate Change and the Timing Problem
Bees and the flowers they pollinate have evolved to be active at the same time of year. As temperatures warm, both groups are shifting earlier, but they do not always shift at the same rate. In alpine environments, earlier snowmelt has been linked to a growing gap between peak wildflower bloom and peak bumblebee worker abundance, a phenomenon called phenological mismatch.9PubMed Central. Phenological mismatch between alpine flowers and bumble bees: its mechanism and impacts on the population dynamics of bumble bees When flowers bloom before bees are ready to forage on them, both parties lose: the bees miss a food source, and the plants miss a pollinator.
How universal this mismatch is remains debated. An analysis of long-term records from generalist bee species found that their emergence dates were advancing at rates similar to the flowering shifts of their host plants, suggesting these bees were keeping pace with warming.10PubMed Central. Climate-associated phenological advances in bee pollinators and bee-pollinated plants However, a separate study of broader bee communities found that bee phenology is less sensitive to climatic variation than flower phenology, pointing to potential for reduced synchrony as warming continues.11PubMed. Bee phenology is predicted by climatic variation and functional traits The risk appears to be greatest for specialist species in mountain environments, where the timing windows are narrower and options for alternative food sources are limited.
Air Pollution Degrades the Signals Bees Rely On
An underappreciated threat is air pollution. Common pollutants like nitrogen oxides from vehicle exhaust and ground-level ozone chemically alter the volatile compounds that flowers release as scent signals. Even moderate ozone levels can substantially degrade these floral volatiles, changing their composition enough that bees struggle to find flowers and take longer to forage.12Atmospheric Environment. Air pollutants degrade floral scents and increase insect foraging times Laboratory and field work has shown that common air pollutants can disrupt the cues that pollinators use to locate and pollinate flowers.13PubMed. Anthropogenic air pollutants reduce insect-mediated pollination services
Bumblebees exposed to elevated ozone showed reduced ability to orient toward flowers using scent, most likely because the ozone was destroying the chemical signals before they could reach the bee or directly affecting the bees’ olfactory system.14PubMed. Effect of ozone exposure on the foraging behaviour of Bombus terrestris This is a problem that does not get the headlines that pesticides or Varroa mites do, but it affects every pollinator in polluted areas, wild and managed alike.
When Helping Honey Bees Hurts Wild Bees
Urban beekeeping has surged in popularity over the past decade, fueled by concern about bee declines and the appeal of local honey. But adding large numbers of managed honey bees to a landscape creates competition for the same floral resources wild bees depend on. In urban settings, higher honey bee abundance has been linked to lower wild bee species richness, with the strongest negative effect on small-bodied wild bee species that have limited foraging ranges.15PubMed Central. Decline in wild bee species richness associated with honey bee (Apis mellifera L.) abundance in an urban ecosystem
The pattern holds in agricultural landscapes too. Among the handful of studies that directly measured wild bee reproduction and growth alongside honey bee density, the majority found negative impacts on wild bees, including reduced growth and reproductive output in bumblebees.16PubMed. Floral Resource Competition Between Honey Bees and Wild Bees: Is There Clear Evidence and Can We Guide Management and Conservation? Migratory beekeeping, where thousands of hives are trucked across regions for pollination contracts, adds another layer of risk by stressing the transported bees, concentrating pathogens, and potentially spilling those pathogens over into local wild pollinator communities.17International Journal for Parasitology: Parasites and Wildlife. Migratory beekeeping and its influence on the prevalence and dispersal of pathogens to managed and wild bees Conservation of pollinators requires thinking beyond honey bees alone.
Wild Bees Do Work That Honey Bees Cannot Replace
This distinction matters because wild bees are not just backup pollinators. A global analysis of 41 crop systems found that wild insect visitation was universally associated with better fruit set, while honey bee visitation was associated with improved fruit set in only about 14% of the systems studied. Per visit, wild insects were twice as effective at boosting yields as honey bees.18PubMed. Wild pollinators enhance fruit set of crops regardless of honey bee abundance A more recent global analysis found that wild insects and honey bees contribute roughly equal total amounts to crop yields, with similar visitation rates and per-visit effectiveness.19Global Ecology and Biogeography. Wild insects and honey bees are equally important to crop yields in a global analysis Regardless of which estimate you lean toward, the message is the same: relying on managed honey bees alone would leave a major gap in pollination services.
For crops like apples, research has shown that wild bee species richness, not just the presence of any one pollinator, is what drives better pollination. Managed honey bees could not substitute for that diversity.20Journal of Applied Ecology. Species richness of wild bees, but not the use of managed honeybees, increases fruit set of a pollinator‐dependent crop This makes the decline of wild bee species a food-security issue, not just an environmental one.
Habitat Restoration That Actually Works
The most straightforward way to support wild bee recovery is to give them places to eat and nest. Wildflower strips planted along crop field edges have become one of the most common and most studied interventions. They work. Bees nesting near wildflower strips made shorter foraging trips, produced more offspring, and experienced lower rates of parasitism compared to bees in unrestored areas.21Journal of Applied Ecology. Wildflower strips enhance wild bee reproductive success Smaller bee species, which have limited flight ranges and are therefore most vulnerable to isolated landscapes, benefited the most.
Getting the planting right matters. Research across multiple U.S. regions found that native wildflower mixes attracted greater abundance and diversity of wild bees, and that the size of the floral display was a key driver. Critically, mixes designed to bloom continuously throughout the growing season supported the greatest species richness, because different bee species are active at different times of year.22PubMed. Native wildflower plantings support wild bee abundance and diversity in agricultural landscapes across the United States A patch of flowers that blooms for three weeks in June and then goes bare does less than a diverse planting that offers something from April through September. Many European agri-environment schemes now subsidize these wildflower plantings along field margins as a standard tool for supporting pollinators and other beneficial insects.23Journal of Applied Ecology. Can rolling composite wildflower blocks increase biodiversity in agricultural landscapes better than wildflowers strips?
Breeding Bees That Fight Back Against Mites
Rather than relying solely on chemical treatments against Varroa, some breeding programs are selecting for honey bees that manage the mite on their own. The most promising behavioral trait is called Varroa sensitive hygiene, or VSH, in which worker bees detect and remove mite-infested pupae from their cells, interrupting the mite’s reproductive cycle.24PubMed Central. Honey bees (Apis mellifera) preselected for Varroa sensitive hygiene discriminate between live and dead Varroa destructor and inanimate objects Bees bred for high VSH can distinguish between infested and uninfested cells with impressive accuracy, and the trait also appears to confer resistance to other brood diseases like chalkbrood.25PubMed Central. Honey bees bred for Varroa sensitive hygiene trait demonstrate resistance to chalkbrood disease
The challenge is consistency across generations. A large-scale breeding effort that crossed high-VSH queens and drones from 2019 to 2022 found remarkable variability in VSH levels among their offspring, likely because honey bees have a high rate of genetic recombination that shuffles traits unpredictably from one generation to the next.26Apidologie. The selection traits of mite non-reproduction (MNR) and Varroa sensitive hygiene (VSH) show high variance in subsequent generations and require intensive time investment to evaluate Breeding for mite resistance is a real and promising avenue, but it is slow, labor-intensive work that does not yet offer a plug-and-play solution for beekeepers.
On the disease front, a different approach has shown potential: a vaccination-like strategy against American foulbrood, one of the most devastating bacterial diseases of honey bee brood. By exposing queen bees to killed bacteria, researchers triggered a form of immune priming that was passed to offspring, providing some protection without harming colony performance.27PubMed Central. Trans-generational immune priming against American Foulbrood does not affect the performance of honeybee colonies This is still early-stage work, but it represents a genuinely new tool in bee health management.
Diversifying the Pollinator Workforce
One response to the fragility of depending so heavily on a single managed species has been growing interest in other bee species that can be commercially reared for pollination. About five bumblebee species are now used for crop pollination in greenhouses, with Bombus terrestris dominant in Eurasia and Bombus impatiens in North America.28Apidologie. A century of advances in bumblebee domestication and the economic and environmental aspects of its commercialization for pollination Several solitary bee species in the Osmia and Megachile genera are used for orchard and seed pollination, though only about eight species are commercially available worldwide despite many more being suitable candidates.29Current Research in Insect Science. The utility and use of solitary bees for pollination in greenhouses and other covered growing systems: A review Expanding the roster of managed pollinator species is a form of agricultural insurance against honey bee losses, and it distributes the pressure more evenly rather than loading it all onto one species.
Technology and Citizen Science as Monitoring Tools
One of the fundamental problems in answering whether bees are recovering is that we often do not have good baseline data on wild bee populations. For managed honey bees, hive-mounted sensor systems can now track weight, temperature, humidity, carbon dioxide levels, and acoustic signatures in real time, giving beekeepers and researchers early warnings about colony health before problems become visible.30PubMed Central. A Smart Sensor-Based Measurement System for Advanced Bee Hive Monitoring
For wild bees, the monitoring gap is being partially filled by citizen science. Projects like Italy’s Beewatching initiative have used public photo submissions to collect distribution data on wild bee genera. Over two years, the project received over a thousand reports covering 38 bee genera on 190 plant genera, including sightings of an invasive species, Megachile sculpturalis.31PubMed Central. Beewatching: A Project for Monitoring Bees through Photos Similar projects exist elsewhere, including Oxford Plan Bee, which focuses on solitary bee populations and aims to provide data that can feed into models predicting local decline.32PLANTS, PEOPLE, PLANET. Network modelling, citizen science and targeted interventions to predict, monitor and reverse bee decline These efforts are no substitute for systematic surveys by trained entomologists, but they are generating data in regions and at scales that professional monitoring alone could never cover. Tracking invasive species and documenting range shifts are the kinds of signals that become visible only when thousands of observers are contributing records from their own gardens and neighborhoods.