Bees pollinate 71 of the 100 crop species that provide 90 percent of the world’s food. They also pollinate wild plants and thus contribute to the preservation of biodiversity and the beauty of nature.

But climate change, pesticides and parasites are taking a terrible toll on bees and they need to be protected, according to European beekeepers holding their annual congress in Quimper, western France, this week.

The congress, which said some European beekeepers are suffering “significant deaths and disastrous harvests due to difficult climatic conditions,” was an opportunity for beekeepers and scientists to try to respond to the major concerns.

The European Union, the second largest honey importer in the world, currently produces only 60 percent of what it consumes.

French beekeepers, for example, expect to harvest between 12,000 and 14,000 tonnes of honey this year, far less than the 30,000 tonnes they harvested in the 1990s, according to the National Federation of French Beekeepers (UNAF).

“I’ve been fighting for bees for 30 years, but if I had to choose now I don’t know if I would become a beekeeper,” said UNAF spokesman Henri Clement, who owns 200 beehives in the unspoilt mountainous region of the Cevennes in south-eastern France.

Clement is 62 and nearing retirement.

“But for young people who want to take up the profession, it’s not much fun,” he said.

Many of the topics floating around at the congress bear witness to this: Asian hornets, parasitic Varroa mites and hive beetles (all invasive alien species in Europe), pesticides and climate change.

With climate change, “the bigger problem is just the erratic weather and rain patterns, drought and things like that,” said US entomologist Jeffery Pettis, president of Apimondia, an international federation of beekeepers’ associations in 110 countries.

“In certain places, the plants were used to a certain temperature. And now it’s going up and you’re having a hot, dry summer and there are no flowers,” Pettis told AFP.

No flowers means no pollen, which means bees are dying of starvation.

Climate scientists say human-caused global warming is amplifying extreme weather events, such as floods and heat waves, which are making wildfires worse.

“The fires seem to be a big problem,” Pettis said. “They come sporadically and we’re losing hives directly to floods and fires.”

Pettis, a former U.S. Department of Agriculture scientist, published a 2016 study on the quality of pollen from goldenrod — a hardy perennial also known as solidago that produces a multitude of small, yellow, daisy-like flowers.

The study showed that the more carbon dioxide – a greenhouse gas – accumulates in the atmosphere, the lower the amount of protein in goldenrod pollen.

Bees in North America depend on a diet of goldenrod pollen to survive the winter, Pettis explained.

“Getting inferior food…should affect hibernation. It could happen with other pollen sources. We do not know it.”

As in France, 30 to 40 percent of hives in the United States die each winter, Pettis said, depleted by varroa mites, pesticides and the destruction of wild areas where wild plants grow.

“Today there are even American startups developing drones to pollinate plants instead of bees. It’s absolutely appalling,” Clement said.

Toxic pesticides are another factor decimating bee colonies and other pollinating insects.

French molecular biophysicist Jean-Marc Bonmatin said parasites like Varroa are “enhanced by the presence of neonicotinide pesticides that directly poison pollinators.”

Neonicotinides, chemically similar to nicotine, are systemic pesticides.

Unlike contact pesticides, which remain on the surface of treated leaves, systemic pesticides are taken up by and transported through the plant, to its leaves, flowers, roots and stems, and to its pollen and nectar.

These toxic substances can remain in the soil for anywhere from five to 30 years, Bonmatin said.

The EU restricted the use of three neonicotinides — but not all — in 2013, and banned them entirely in 2018.

But since 2013, several EU countries have repeatedly issued “emergency permits” for the use of the harmful insecticides on large crops.

He said open-source software, called Toxibee, will soon be launched to help farmers protect bees by identifying the least toxic molecules to use on their crops.

“Before spraying the crops with pesticides, they can try to limit their harmful effects,” he said.

“Because what kills bees will one day also harm people’s health.”

However, Pettis struggled to remain optimistic and pointed to a few ways people can help bees.

“(We should) diversify agriculture and try not to be driven by chemical-dependent agriculture, but to support organic and more sustainable agriculture.”

He also highlighted the incredible resilience of some bee species, aided by factors in the natural world.

He gave the example of a black bee found on the island of Ile de Groix in Brittany that survived Varroa attacks without beekeepers treating them for mites or giving them extra food.

“We think the bees depend on us, but in reality they survive pretty well without us,” he said.

“And you still have the beauty of bees. It’s such a good thing to work with bees.”