“Man of work, woke up and recognize your power, all wheels stand still when your strong arm wants it,” says the founding song of the General German Workers’ Association, from which the SPD later emerged. What was true in the factory halls of the 19th century also seems to be of importance for the modern agricultural industry: industrious bees stay away from the cultivated areas, the pollen is not distributed, fruits do not ripen, and the harvesting machines are just as quiet as the steam engines 150 years ago . The flying proletarians of the fields, however, do not voluntarily go on the general strike – there are simply fewer and fewer. For the most part, industrial agriculture is responsible for the death of insects; Fertilizers, pesticides and the loss of natural habitats have decimated stocks worldwide.

The serious consequences of the extinction of many insects for flora and fauna has long been known. However, a new study by US and Canadian researchers shows how much agriculture itself suffers from homemade insect dieback: in the large cultivation areas of North America, insects are no longer pollinating apple, blueberry and cherry blossoms enough, which is causing the harvests to shrink noticeably. This is reported by the 31 scientists around the biologist James Reilly in their study, which was published in the specialist journal this Wednesday Proceedings of the Royal Society B has appeared.

The fewer insects flew across the orchards, the fewer fruits grew on trees and shrubs

The researchers systematically examined which popular and therefore mass-grown fruits in North America suffer from the lack of bees and other pollinators. To this end, they visited 131 cultivated areas and counted honey bees, wild bees and other insects that flew to flowers there. The researchers compared these figures with the crop yields of the farms visited. They found a clear connection in apple, cherry and blueberry farms: the fewer insects flew across the orchards, the fewer fruits grew on trees and shrubs. However, melons, almonds and pumpkins have so far hardly been affected by insect death.

In order for the lack of bees to cause the harvests to shrink substantially, the fruits must above all be healthy. Because if diseases, pests, dryness or a lack of nutrients cause fewer flowers to grow anyway, the lack of pollinators is of little importance: Even swarms of bees that are severely decimated can then cope with the comparatively few flowers.

The biologists estimate the value of wild bee work at just under 1.3 billion euros

The researchers also found that wild bees – many of which are threatened with extinction – and honeybees split the work fairly fairly. Even in intensively cultivated areas, wild bees pollinated almost as many plants as honey bees, which are bred by beekeepers. For a long time, it was assumed that honeybees are more important than wild bees for agricultural production. However, a few years ago, studies indicated that wild bees do at least as much. Scientists say honey bees fly more often, but wild bees carry more pollen per flight. However, the researchers rarely observed other pollinating insects such as flies or butterflies on the plantations examined. Elsewhere they also play an important role.

One thing is clear: the death of insects causes immense economic damage. The biologists estimate the economic value of wild bee work at just under 1.3 billion euros – for the examined blueberry, apple, cherry, almond, melon and pumpkin cultivation in North America alone. Scientists keep trying to monetize the value of so-called ecological services such as pollination. According to an estimate from 2008, the whole of humanity owes bees, bumblebees and other pollinators more than 150 billion euros for their worldwide service in fields and orchards.

The authors of the study recommend first of all to better protect wild bee populations – especially by growing wild flowers. But they also mention that some farmers are now artificially pollinating their plants, be it with the help of drones or human workers. A few weeks ago, Japanese researchers even reported that they had pollinated fruit blossoms with pollen-containing soap bubbles. The pioneers of the labor movement in the 19th century also predicted that capital would replace workers as soon as technical progress allowed it. Unlike factory workers, however, there are no new jobs for wild bees – their extinction would be irreversible and the damage to nature would be considerable.