Why are bees dying – and can we save them?

When Luciana Porter Bolland first traveled to the municipality of Hopelchén in the Mexican state of Campeche to work on her doctoral thesis, beekeeping was not only an important source of income for the Indigenous Maya but a tradition dating back to pre-Columbian times.

The Maya word for bee – ‘kaab’ – also means ‘force,’ and the insect itself is a symbol of fertility and abundance.

Two decades later, the stingless bees of the Yucatán Peninsula are disappearing, along with the tropical landscape in which it once thrived.

By 2021, almost 154,000 hectares of tree cover had been lost to commercial monoculture crops in Hopelchén alone, according to Global Forest Watch, and the impact on both the abundance and species diversity of bees has been severe. 

 “Communities are being affected because there has been so much deforestation,” says Porter Bolland, now a senior researcher at the Institute of Ecology (INECOL). “There have been massive die-offs in the bee populations and reductions in production yields.”

Many families in the area have now abandoned their livelihoods in what was once a major honey-exporting area.

In many ways, the region is a microcosm of what’s happening to bees globally. All over the world, researchers and beekeepers have reported declines among both managed species, like honeybees (apis mellifera), and the thousands of wild species that vastly outnumber them.

In the U.S., for example, there has been an almost 40 percent mortality rate in managed bee colonies over the past 12 years, according to annual surveys carried out by the Bee Informed Partnership.

Similarly, in China, the world’s largest exporter of honey and home to a vast array of bee diversity, wild bee populations are in rapid decline and have vanished altogether from some areas.

Globally, a quarter of all known bee species haven’t been recorded since the 1990s, another analysis has found.

Pollinator power

While observations of bee decline are often local and not easily measured, what is undeniable is the crucial importance of the world’s more than 20,000 species of bees.

Aside from providing livelihoods for thousands of rural and Indigenous beekeepers, bees play an essential role in pollinating plants – helping sustain the planet’s biodiversity and safeguarding our food supply.

According to a 2016 assessment report from the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), pollinators contribute to 35 percent of global crop production by volume. They also boost the quality and yields of most major global food crops.

Bees also play an important role in natural ecosystems, such as mangrove forests, says Levis Sirikwa, a GLF Restoration Steward who works with communities on sustainable coastal agriculture and restoring mangroves in Kenya.

“Most of the flowers in the mangroves are pollinated by bees, enhancing the diversity and population of trees,” he says. Replanting mangroves can be very expensive, “but the bees are actually helping us do natural restoration,” he adds.

“In other words, the system is restoring itself. So, the resources we mobilize will be focused less on planting mangrove and more on supporting alternative land use and other productive activities.”

According to many pollinator experts, the main drivers of bee decline worldwide are habitat loss and the intensification of agriculture. As farming replaces mixed crops and mosaic landscapes, both native and managed bee species are under attack.

The expanding soy farms on Mexico’s Yucatán Peninsula are a prime example. But globally, too, “the landscape has changed to production systems based on making agriculture more efficient through single crops,” says Porter Bolland.

“This implies the use of pesticides and herbicides, getting rid of weeds whose flowers provide food for bees and other pollinators.”

According to a 2019 study she co-authored, some high-intensification agricultural landscapes host only half the bee species diversity of low-intensification landscapes.

Climate conundrum

The climate crisis is also having an effect on bees, says Shelley Hoover, an associate professor at the University of Lethbridge in Alberta, Canada.

“As climate changes, you can see a phenological mismatch between plants and pollinators,” she says. “Honeybees are around all year, but some native bee species have a very short window in which they’re active as adults. That is often matched to a particular plant species or group of plant species.”

A mismatch occurs if flowers bloom too early for the bees because of warmer temperatures, taking away their food source when they need it.

“The other thing we see are these extreme weather events,” says Hoover. “It could be extreme heat or extreme cold, floods or forest fires. A forest fire in British Columbia, for example, will affect how much honeybees can forage as far away as Alberta or even Saskatchewan.”

Climate change has posed major challenges in Kenya, too. “In 2022, there was a lot of dry spells, longer than expected, [and] a lack of fresh water from seasonal rivers,” says Sirikwa.

“Then, in 2023, there was unexpected rain, so areas that [were] dry got flooded. If hives are not at the right height, and water infiltrates the hives, the bees relocate.”

Signs of stress

In the United States, the Bee Informed Partnership, a non-profit organization that uses data to improve the health of honeybees, has found that the presence of the varroa mite in hives has been a consistent problem. 

“It may not be every single year or every type of operation, but it’s among the top three [reasons for bee mortality] every year,” says Geoffrey Williams, the partnership’s president and an associate professor of entomology and plant pathology at Auburn University in Alabama.

‘Queen issues’ – when queen bees lose their ability to maintain the worker bee population – have also been cited, as well as lack of forage, or flowers, in the landscape.

There are several studies, says Williams, “showing that bees respond better to other stressors when they have diverse sources of food that can buffer the effects of pesticides or parasites, rather than a single pollen source.”

In both Canada and the U.S., despite numerous reported deaths, the population of honeybees has remained relatively stable, both Williams and Hoover say. “Honeybees have serious issues, but we really haven’t appreciably lost population [in Canada],” says Hoover.

Nonetheless, Williams agrees that North American native bees are in bigger trouble. While not every species is affected, some are under severe pressure. “There’s no doubt all our human influences on the environment are heavily influencing the status of our native bees too in loss of habitat and diverse food sources,” he says.

And while beekeepers can deal with losses in their colonies, it can be expensive and time-consuming, says Williams.

“We can’t not worry about the honeybees, because these beekeepers are at breaking point – when the industry as a whole has such high losses that they can’t even rebound the next year.”

Can we stop bee decline?

Bee experts agree that changes to agricultural and food systems will be needed to halt the decline in both managed and wild bees.

“Harmonizing productive systems with diverse landscapes, agroforestry and using a land-sharing rather than land-sparing approach could help bees and other pollinators,” says Porter Bolland.

For wild bee species in particular, preserving natural areas is vital to ensuring they can find both food and nesting sites. “Just like every other animal out there, bees need space. Preserving space works whether it’s bees or caribou,” says Hoover. “All the animals benefit.”

Regulating and reducing pesticide use would also represent a major win for both the bees and global food systems.

In Hopelchén, local beekeeper Leydy Pech showed what could be accomplished when she took Monsanto (now owned by Bayer) to court and proved that its use of glyphosate-based herbicides threatened the livelihoods of Mayan communities and their environment.

In 2017, Mexico’s agriculture ministry revoked Monsanto’s permit to grow genetically modified soy.

Homeowners, schools and city governments can all do their bit to ensure bee survival by simply planting flowering species in gardens, in schoolyards and along roads, she adds, “putting flowers in as many places as we can.”

“All the things that would help bees would also help us,” says Williams. “Improvements to the environment. More diverse habitat. Better food. A reduction in the use of pesticides.”