The Swiss voice in the world since 1935
Top stories
Stay in touch with Switzerland

Mites and insecticides prove killer combo for honey bees

honey bee
Since 1985, the total number of bees in Switzerland has fallen by a quarter. Keystone-sda-ats Ag Switzerland

Swiss researchers have shed light on the whys behind the rapid decline of the honey bee with a study focused on the combined effect of two key stressors.

Researchers from the Institute of Bee Health at the University of BernExternal link and the COLOSS honey bee research associationExternal link studied the “combination effect” of two stress factors: insecticides and a type of mite.

The researchers treated workers in honey bee colonies with two selected insecticides (neonicotinoids). These had no influence on the weight and longevity of the bees, according to a statement by the University of Bern on Tuesday.

However, as soon as the Varroa mite entered the mix, a harmful interaction of the two factors could be demonstrated.

The researchers have published their results in Scientific ReportsExternal link, the open access platform of the scientific journal Nature.

Winter bees particularly affected

Winter bees, which are born in autumn to ensure the survival of the colony over the coldest months, were particularly hard hit,

The negative “combined effect” not only led to a shorter lifespan of the winter bee workers, but also took a toll on body size. Body size is crucial to how well winter bees can defend their body temperature against the cold.

   + Wild bees in danger (VIDEO)

   + A look at the bee that thrives in Swiss Alpine valleys

Sustainable solutions in demand

The researchers are therefore calling for sustainable solutions in agriculture.

“Reduced use of insecticides and improved control of the Varroa mite are urgently needed,” says Lars Straub, lead author and post-doctoral fellow at the Institute for Bee Health.

The western honey bee (Apis mellifera) is by far the most important human pollinator. In recent years there have been high losses of honey bee colonies worldwide.

The Varroa mite originates from AsiaExternal link, where it affects the eastern honey bee. It is considered the most dangerous biotic threat to honeybees worldwide.

More


Popular Stories

Most Discussed

News

Solar aeroplane flies around the Matterhorn

More

Solar plane flies around Matterhorn

This content was published on Solar energy pioneer Raphaël Domjan and his team continued preparations for the altitude record attempt at 10,000 metres with the SolarStratos solar aircraft.

Read more: Solar plane flies around Matterhorn
Compulsory vaccination against cattle disease in Geneva and parts of Vaud

More

Vaccinations imposed for some Swiss cattle

This content was published on Cattle in the canton of Geneva and in the neighbouring region of Terre Sainte in the canton of Vaud are being vaccinated against the contagious viral skin nodule disease. The first cases of the animal disease were reported at the end of June in France, just outside Geneva.

Read more: Vaccinations imposed for some Swiss cattle
Small rockfalls occurred above Brienz GR

More

Rockfalls measured above Swiss village

This content was published on A series of rockfalls occurred above the village of Brienz between 9 and 12 July. According to the municipality of Albula, the overall situation remains tense. Several people disregarded the ban on entering the area around the village.

Read more: Rockfalls measured above Swiss village
Arosa Bergbahnen with record sales

More

Arosa cable cars celebrate record year

This content was published on Arosa Bergbahnen achieved the highest figure in its 95-year history in the 2024/25 financial year with net revenue of CHF 37 million. Arosa Lenzerheide was able to capitalise on strengths such as snow reliability and the size of the ski area in a long winter season, the company announced on Thursday.

Read more: Arosa cable cars celebrate record year
Unknown persons steal dental implants from Solothurn company

More

Dental implants stolen in million-franc raid

This content was published on Unknown perpetrators stole ceramic dental implants during a break-in at a company in Oensingen, northern Switzerland, on Tuesday night.

Read more: Dental implants stolen in million-franc raid
Rockfalls affect tourism at the Grande Dixence dam

More

Rockfalls affect tourism at tallest dam in Europe

This content was published on The Grande Dixence dam in Lower Valais is closed to visitors due to a rockfall last weekend. The nearby hotel also had to temporarily suspend operations for safety reasons.

Read more: Rockfalls affect tourism at tallest dam in Europe

In compliance with the JTI standards

More: SWI swissinfo.ch certified by the Journalism Trust Initiative

You can find an overview of ongoing debates with our journalists here . Please join us!

If you want to start a conversation about a topic raised in this article or want to report factual errors, email us at english@swissinfo.ch.

SWI swissinfo.ch - a branch of Swiss Broadcasting Corporation SRG SSR

SWI swissinfo.ch - a branch of Swiss Broadcasting Corporation SRG SSR