Due to Climate Change, Bee Population in Bulgaria Has Declined Significantly in Recent Years

The bee population in Bulgaria has declined significantly over the past four years due to climate change. This has had a negative impact on the harvest of Bulgarian fruit.

Nikolay Gaydov, from the village of Rzhevo Konare, Plovdiv district, Southern Bulgaria, takes care of 150 beehives. With winter approaching, he wants to make sure that the colonies are prepared.

“By my estimates, there are around 30–35,000 bees in a hive at the moment. We aim to keep the colony at full strength. The number of bees must be sufficient so that they can start developing at the end of January and beginning of February,” said Gaydov, a beekeeper.

For 15 years, the beekeeper has been closely observing the climate in the region with concern. According to him, the changes are now happening so quickly that bees cannot adapt or follow their biological rhythm. Spring has become a major challenge for them. Early warming followed by late spring frosts confuses both plants and insects.

“Neither the plants were ready — there were no blossoms to pollinate — nor did the bees manage to collect nectar to survive. As a result, bee colonies collapsed. We have been seeing this for two or three years now. The climate changes are severe,” Gaydov commented.

For more than 100 million years, bees have adapted to changes in the environment, fulfilling their biological role to ensure fruit and honey production. But in recent years in Bulgaria, output has been falling, also due to environmental changes.

As a result of disturbed balance, harvests of cherries, apples and peaches are decreasing.

“This year was a complete failure for cherries. It’s no coincidence that prices at the peak of the season reached around 16 leva (BGN) per kilo. People were outraged. It often happens, especially here in the Thracian Plain, that when freezing temperatures come down from the Rhodope Mountains to the lowlands, enormous damage is caused — blossoms are destroyed and the forage for bees disappears,” said agricultural producer Krasimir Kumchev.

A group of biologists, including two university lecturers from Plovdiv, have carried out a large-scale study on bee colony mortality over the past seven years. The trend is worrying — pesticides and climate stress are causing environmental pressure that bees cannot withstand.

“We confirmed through chemical analysis that over 35 different pesticides have toxic effects that influence the rate of cell division, but more dangerously, cause structural chromosomal changes,” said Prof. Evgeniya Ivanova of Paisii Hilendarski University of Plovdiv.

There are apiaries in the country that have lost over 90% of their colonies.

“Over the past five to seven years, climate changes have occurred that are particularly challenging for bees. These include long, cold, prolonged springs followed by very rapid periods of extremely high temperatures and severe drought lasting four to six months — as happened this year,” commented Prof. Plamen Petrov from the Agricultural University in Plovdiv.

Research shows that bees in Southern European countries are far more affected than those in the north. New climate conditions will require resilient solutions.

“In order for beekeepers to adapt their practices to the changing climate, national-level strategies are needed to support beekeeping, so that beekeepers can survive under the new conditions,” said Prof. Petrov.

Bees are the only insects in the world capable of reproducing the environment in which they live. Scientists estimate that 80% of global pollination depends on them. They warn that their disappearance could have catastrophic consequences for food supply and life on earth.