Bees really are in trouble, but “bee decline” describes two different problems that are easy to blur together. Beekeepers lose a large share of their honey bee hives every year and rebuild them, while many wild bee species are quietly disappearing from farmland. No single villain explains either one; the damage comes from several stresses that make each other worse.
How Many Honey Bee Colonies Are Lost Each Year
A colony is the whole family living in a hive: one queen, thousands of workers and their young. Across 35 mostly European countries, beekeepers lost about 16.7% of their colonies over the 2018–2019 winter.1Journal of Apicultural Research. Honey bee colony winter loss rates for 35 countries participating in the COLOSS survey for winter 2018–2019, and the effects of a new queen on the risk of colony winter loss Of that, about 10.7% simply died, 4.1% had queen problems that couldn’t be fixed and 1.9% were lost to disasters like floods or storms.2Journal of Apicultural Research. Honey bee colony winter loss rates for 35 countries participating in the COLOSS survey for winter 2018–2019, and the effects of a new queen on the risk of colony winter loss The next winter losses rose to about 18.1%, with country rates ranging from 7.4% to 36.5%.3Journal of Apicultural Research. Honey bee colony loss rates in 37 countries using the COLOSS survey for winter 2019–2020: the combined effects of operation size, migration and queen replacement Depending on where a beekeeper lives, that can mean losing 1 hive in 14 or more than 1 in 3.
A hive without a working queen can’t produce new workers, so it dwindles. Beekeepers count it as a loss even if plenty of bees are still alive inside.
Other regions lose more. In Latin America, beekeepers lose about 30.4% of honey bee colonies per year, and 39.6% of native stingless bee colonies.4PubMed. First large-scale study reveals important losses of managed honey bee and stingless bee colonies in Latin America Looking only at winter, Latin America sits at about 20.6%, between Europe at 12.5% and the United States at 40.4%.5PubMed. First large-scale study reveals important losses of managed honey bee and stingless bee colonies in Latin America New Zealand beekeepers reported about 10.5% winter losses.6Journal of Apicultural Research. Honey bee colony loss rates in 37 countries using the COLOSS survey for winter 2019–2020: the combined effects of operation size, migration and queen replacement
These numbers come from beekeeper surveys that ask how many colonies were alive in autumn and how many made it to spring, so they depend on what beekeepers report. Survey groups also define the loss period differently, with some counting only winter and others a full year. That’s why the Latin American annual figure shouldn’t be compared directly with the winter figures.
A lost colony also isn’t lost bees forever. Each spring, beekeepers split strong hives or buy new queens to replace what died, so total hive counts can stay steady even when losses are high. The real cost falls on beekeepers in money, time and stress.
Honey Bees Versus Wild Bees
Unlike some native bees, honey bees are not at risk of going extinct.7UMN Bee Lab. Bee Population Decline: The Statistics and Causes People keep, breed and move them, so their numbers are propped up by beekeeping. Still, there is clear evidence of declines in both wild and domesticated pollinators, along with the plants that depend on them.8Elsevier / Trends in Ecology & Evolution. Global pollinator declines: trends, impacts and drivers
There are thousands of bee species beyond the honey bee, and most are solitary, nesting in the ground or in stems. Bumblebees, mason bees and sweat bees are common garden examples.
Honey bees can also add pressure on their wild relatives. Where honey bees are abundant, they drain pollen and nectar from flowers that native bees also need, so native bees shift which flowers they visit.9PubMed. Evidence of exploitative competition between honey bees and native bees in two California landscapes As honey bee numbers rise, the nutritional quality of native bee diets falls.10Journal of Applied Ecology. Wildflower plantings and honeybee competition impact nutritional quality of wild bee diets Honey bees can also pass diseases to wild bees, sometimes shortening their lives.11Discover Animals. Pathogen spillover from honey bees (Apis mellifera L.) to wild bees in North America
Keeping hives therefore doesn’t save wild bees: it boosts one farmed species. In areas with few flowers, extra hives can make food scarcer for native bees. Planting flowers helps both groups more than adding hives does.
Varroa Mites and the Viruses They Spread
The Varroa mite is a tiny parasite that feeds on developing and adult honey bees. It carries deformed wing virus, and together they are a major threat to the world’s honey bees.12PubMed. Deformed wing virus is a recent global epidemic in honeybees driven by Varroa mites The mite injects the virus directly as it feeds, which turned a once minor virus into a worldwide, human-driven epidemic.13PubMed. Deformed wing virus is a recent global epidemic in honeybees driven by Varroa mites
A mite-damaged hive is easy to recognize once you know what to look for. Young bees emerge with crumpled, useless wings. The hive shrinks through late summer and autumn, and it often dies over winter, which feeds straight into the loss figures. Beekeepers who check and treat for mites cut this risk.
Disease can jump to wild bees too. Infected honey bees readily pass deformed wing virus to bumblebees in close contact.14PubMed Central. Experimental cross species transmission of a major viral pathogen in bees is predominantly from honeybees to bumblebees Bacteria, fungi and other parasites of honey bees also infect wild bees.15Discover Animals. Pathogen spillover from honey bees (Apis mellifera L.) to wild bees in North America16Conservation Science and Practice. Assessing pathogen risk for wild bumblebees (Bombus spp., Apidae) in Canada
Colony collapse disorder is when adult bees vanish from a hive, leaving the queen, young and food behind with few dead bodies.17Wikipedia. Colony collapse disorder It made dramatic headlines, but most colony deaths come from other causes such as mites, disease, queen failure or poor nutrition.18Wikipedia. Colony collapse disorder
Pesticides and Weed Killers
Neonicotinoids are a widely used group of insecticides that plants absorb, including into their pollen and nectar. Non-lethal doses can stop foraging honey bees from recalling the routes home they learned.19PubMed Central. Neonicotinoids Interfere with Specific Components of Navigation in Honeybees A bee that can’t navigate back is lost to the colony. The common weed killer glyphosate also disrupts the helpful gut bacteria of honey bees and makes them more prone to infection.20PubMed Central. Glyphosate perturbs the gut microbiota of honey bees
Wild bees in fields fare poorly as well. Higher pesticide hazard in crop fields means fewer wild bees and fewer kinds of them.21PubMed Central. Pesticides and habitat loss additively reduce wild bees in crop fields In England, wild bees exposed more to neonicotinoid pesticides were less likely to persist in an area over the long term.22PubMed Central. Impacts of neonicotinoid use on long-term population changes in wild bees in England In England, wild bees that forage on oilseed rape, a neonicotinoid-treated crop, were hit about three times harder than those that don’t.23PubMed Central. Impacts of neonicotinoid use on long-term population changes in wild bees in England
In your own yard, you can cut the risk. Skip insecticides on plants in bloom, and check plant labels at garden centers for systemic insecticide treatment. If you do need to spray, do it in the evening when bees aren’t foraging. Tolerating some leaf damage is often better than spraying at all.
Habitat Loss and Poor Nutrition
Intensive farming reduces the number, variety and diversity of wild bees.24Agriculture, Ecosystems and Environment. Intensification of agriculture, landscape composition and wild bee communities: A large scale study in four European countries Bee variety rises, though, with the amount of hedgerows, meadows and other semi-natural land nearby.25Agriculture, Ecosystems and Environment. Intensification of agriculture, landscape composition and wild bee communities: A large scale study in four European countries Habitat loss and pesticides add up, each removing bees on top of the other.26PubMed Central. Pesticides and habitat loss additively reduce wild bees in crop fields
Flower variety matters for health as well as numbers. Honey bees fed pollen from many plants have stronger immune defenses than bees fed one kind.27PubMed Central. Diet effects on honeybee immunocompetence Simply giving them more protein doesn’t boost immunity.28PubMed Central. Diet effects on honeybee immunocompetence Huge fields of one crop can therefore leave bees well fed but poorly nourished.
A single crop blooms briefly, then leaves nothing, while bees need flowers from early spring to autumn. Mown lawns offer almost no pollen or nesting space.
Nesting matters as much as flowers. Most wild bees nest in bare soil, dead stems or wood, and tidy gardens remove these sites. Leaving some bare ground and old stems gives bees homes.
Climate Change and Other Stresses
When spring comes early, flowers can open before overwintering bumblebee queens emerge, so those flowers get fewer visits and set fewer seeds.29Ecology. Early onset of spring increases the phenological mismatch between plants and pollinators In mountain meadows, earlier snowmelt widens the gap between flowering and worker bumblebee activity.30PubMed Central. Phenological mismatch between alpine flowers and bumble bees: its mechanism and impacts on the population dynamics of bumble bees
Some stresses are less studied. Honey bees visit fewer flowers near active electric transmission towers, possibly because the fields disturb their navigation.31PubMed Central. Electromagnetic fields disrupt the pollination service by honeybees Modern breeding has also narrowed honey bee genetics, limiting their ability to evolve resistance to threats like mites.32Conservation Letters. Genetic Bottlenecks in Modern Beekeeping: Implications for Conservation and Sustainable Pollination
Why Several Threats at Once Are Worse
In one experiment, bees exposed to a gut parasite alone reached up to 39% deaths, and bees exposed to the insecticide fipronil alone up to 31%.33PubMed Central. Parasite-insecticide interactions: a case study of Nosema ceranae and fipronil synergy on honeybee Bees exposed to both reached up to 84% deaths.34PubMed Central. Parasite-insecticide interactions: a case study of Nosema ceranae and fipronil synergy on honeybee Sublethal pesticide doses also worsen the harm from common bee diseases in both larvae and adults.35PubMed. Bees under stress: sublethal doses of a neonicotinoid pesticide and pathogens interact to elevate honey bee mortality across the life cycle Combined exposure lowers immunity and could be enough to tip a colony into collapse.36PubMed. Synergistic effects of pathogen and pesticide exposure on honey bee (Apis mellifera) survival and immunity
Asking for one cause misses how the threats feed each other. A hive weakened by poor food is easier prey for mites, and reducing any one stress can leave bees better able to cope with the others.
What Bee Decline Means for Food and Nature
Bee pollination improves both how much food crops produce and their quality.37PubMed Central. Overview of Bee Pollination and Its Economic Value for Crop Production In the short term, a total loss of pollinators would cost an estimated 1 to 2% of global GDP.38Ecological Economics. Revisiting the economic valuation of agricultural losses due to large-scale changes in pollinator populations Declines also threaten wild plant diversity, ecosystem stability and food security.39Elsevier / Trends in Ecology & Evolution. Global pollinator declines: trends, impacts and drivers
Fruits like apples, berries and cherries rely heavily on bees, and so do nuts such as almonds and many vegetables. Staple grains like wheat and rice don’t need bees to pollinate them. The loss would therefore hit variety and nutrition more than calories.
Many wildflowers depend on specific wild bees, and honey bees can’t fill every role. Losing wild bees shrinks the plants that feed other wildlife.
How to Help Bees Where You Live
Small spaces count. City green spaces can host a wide variety of pollinators, and even the smallest green patches improve food and nesting for bees.40PubMed Central. A “plan bee” for cities: Pollinator diversity and plant-pollinator interactions in urban green spaces Community gardens with varied vegetation and nesting spots support diverse bee communities.41PubMed. Vegetation complexity and nesting resource availability predict bee diversity and functional traits in community gardens Urban gardens and plant nurseries both offer many plants but differ in how well they support wild bees.42Sustainability. Wild Bee Conservation within Urban Gardens and Nurseries: Effects of Local and Landscape Management
To plant for bees, choose several native flowering plants with different bloom times, including early spring and late autumn bloomers. Plant in clumps so bees forage efficiently, and favor simple open flowers over heavily doubled ones.
Beyond your own garden, you can ask local councils to mow verges less often and back allotment or community garden plantings. Buying local honey from beekeepers who manage mites carefully supports good practice.
If you keep or plan to keep bees, monitor and treat for mites regularly and replace failing queens promptly. Newer hive sensors can flag problems early, but regular inspection still matters.