In the winter of 2024–2025, 22% of Dutch honeybee colonies died. This marks a slight increase compared to the previous winter and is the third consecutive year with winter mortality above 20%. The figures are based on an annual survey among beekeepers. Regional differences are significant: losses were highest in the province of Utrecht (31.2%) and lowest in Flevoland (11.4%).
The annual survey is conducted by researchers from Wageningen University & Research (WUR), in collaboration with the Dutch Beekeepers Association (NBV), Imkers Nederland, biodynamic beekeepers (BD-beekeepers), and professional beekeepers (BVNI), commissioned by the Ministry of LVVN.
Regional differences
As in previous years, regional differences are evident. Winter mortality is relatively low in the northern provinces, except for Groningen. In North Brabant, North and South Holland, and especially Utrecht, mortality is above the national average. Although the national rate has remained above 20%, patterns vary per region. The precise causes are unknown, but differences in beekeeping practices may play a role.
Various causes
Winter mortality has several causes, which can vary by year and location. Loss of the queen during winter is almost always fatal for a colony. Other contributing factors include food shortage, disease, and pre-winter weakening. The Varroa destructor mite and various bee viruses continue to pose major threats. Controlling Varroa destructor is essential for colony survival. Survey data show that 84.6% of beekeepers treated the mite last winter. This figure lies between previous years: 86.8% (2024) and 81.2% (2023).
Role of the Asian hornet
Whether the spread of the Asian hornet contributes to winter mortality is still unclear. This invasive wasp preys on insects to feed its larvae. Its spread is accelerating: 13.2% of beekeepers reported sightings last year, rising to 27.7% in 2024. While its exact impact remains uncertain, it is expected to increase over time.
Record number of participants
A record number of 3,030 Dutch beekeepers participated in this year's COLOSS survey, conducted in over 40 countries worldwide. This represents nearly 30% of all Dutch beekeepers. The Netherlands has an estimated 11,000 active beekeepers, of whom only 2% are partially financially dependent on their beekeeping. Over half (55%) reported that all their colonies survived the winter, an improvement on last year's 48.3%. Meanwhile, 7.3% reported total loss of their colonies. In 2024, this was 6.7%.
