Swiss Bee Population Crisis: One-Fifth of Colonies Lost Over Winter

Alarming winter mortality rate hits Swiss bee populations, with Lake Geneva region suffering highest losses at nearly 29%

18.9% of Swiss bee colonies failed to survive the winter of 2024/2025.
The mortality rate increased by 4% compared to the previous year.
The Lake Geneva region experienced the highest mortality rate at 28.9%.
Colonies feeding on forest honey had a loss rate of 23.4%, compared to 16.4% for those on other foods.
Melezitose, a sugar found in 'cement honey', causes crystallization that makes digestion difficult for bees.

18.9%

National Winter Mortality Rate

28.9%

Lake Geneva Mortality Rate

Year-on-Year Increase

15.8%

Central Switzerland Mortality Rate

"One in five bee colonies failed to survive the winter."
— Keystone-SDA

"Winter mortality in bee colonies is a complex phenomenon."
— Apisuisse

Winter Wipeout: A National Alarm

18.9% of Swiss bee colonies failed to survive the winter of 2024/2025.
The mortality rate increased by 4% compared to the previous year.
The Lake Geneva region experienced the highest mortality rate at 28.9%.
Colonies feeding on forest honey had a loss rate of 23.4%, compared to 16.4% for those on other foods.
Melezitose, a sugar found in 'cement honey', causes crystallization that makes digestion difficult for bees.