Nearly 15% of bee colonies did not survive the winter in Switzerland. The loss rate is certainly within the average of past years, but there are large regional differences and, within regions, large variations over several years.
According to the annual apisuisse survey of beekeepers, carried out in collaboration with Agroscope and published on Monday, 14.9% of bee colonies did not survive the winter of 2023/2024. This corresponds to the level of the previous year (15%), but is significantly lower than the losses recorded two years ago (21%).
Although 10.1% of overwintered bee colonies survived the winter, they are too weak to develop into a strong bee colony, continues apisuisse. This figure is slightly lower than the previous year (10.9%).
High losses in the Mittelland space
This year again, regional differences appear. The regions of Zurich and the Lake Geneva region (cantons VS, VD, GE) experienced the lowest losses with 13% each.
The highest losses were recorded in the Mittelland Area (BE, FR, SO, NE, JU) with 16.6%, whereas they had been “only” 10.8% last year . Losses are also high in north-west Switzerland (BS, BL, AG, 16.3%). These two regions are above the national average, notes apisuisse.
“Obscure causes”
In the 20th century, losses of up to 10% were often recorded and considered “normal”. Since the early 2000s, higher loss rates have become more frequent and fluctuate from year to year at a high level.
“The losses are partly due to the Varroa mite, but other causes remain obscure,” explains Jean-Daniel Charrière, director of the Beekeeping Research Center.
Lack of flowers in summer
A possible cause is also lack of food. All species of bees, whether honey or wild, need for their development a varied floral offering which provides them with nectar and pollen throughout the season.
However, it is precisely during the summer months that this floral diversity is lacking in many regions. This is why it is important to improve the food supply for bees, says apisuisse.
This article was automatically published. Source: ats
