Honey bee colonies down by 16%

June 05, 2019

The survey of 25,363 beekeepers in 36 countries found that, out of 544,879 colonies being managed at the start of winter, 89124 were lost, through a combination of circumstances including various effects of weather conditions, unsolvable problems with a colony's queen, and natural disaster.

Portugal, Northern Ireland, Italy and England experienced losses above 25%, while Belarus, Israel and Serbia were among those with loss rates below 10%. There were also significant regional variations within some countries, including Germany, Sweden and Greece.

The total loss rate was down from 20.9% in 2016-17 but was still higher than the 2015-16 figure of 12.0%. The total loss rate for Scotland increased over these three years, from 18.0% to 20.4% to 23.7%.

In a departure from previous findings, beekeepers who moved their colonies in the foraging season, to access other forage or for pollination, faced fewer losses than those who kept their bees in the same place. Smaller-scale beekeeping operations also had higher losses than larger ventures.

The study, based on voluntarily submitted information, covered 33 countries in Europe - including the four nations of the UK - along with Algeria, Israel and Mexico.

It has been published in the Journal of Apicultural Research and was carried out by researchers in the colony loss monitoring group of the international honey bee research association COLOSS, which is based in the Institute of Bee Health at the University of Bern.

Dr Alison Gray, a Lecturer in Strathclyde's Department of Mathematics & Statistics, led the study. She said: "Loss of honey bee colonies is a highly complex issue. It tends to be influenced less by overall climate than by specific weather patterns or a natural disaster affecting the colony. We observe colonies in winter but what happens to the bees then can be partly determined by the conditions of the previous summer.

"Many are also lost when there are problems with a colony's queen - for example, if she goes missing or is not laying the fertilised eggs which go on to become worker bees. Most colonies are also under attack from varroa mites, a parasitic mite.

"The impact of beekeepers migrating their colonies would be expected to be partly dependent on the distance travelled and the reasons for migration; this would be worth further investigation."

The study had a focus on sources of forage, plants which bees visit to collect nectar and pollen, in six categories: orchards; oilseed rape; maize; sunflower; heather and autumn forage crops. These were potentially useful food sources for bees, which could help to build up a colony, but, by extending the active and brood-rearing season of the bees, forage which was available late in the season could also extend the reproductive cycle for varroa mites, weakening the bee colonies and making winter losses more likely.
-end-
The research paper can be seen at https://www.tandfonline.com/doi/pdf/10.1080/00218839.2019.1615661?needAccess=true&

University of Strathclyde

Related Bees Articles from Brightsurf:

Two pesticides approved for use in US harmful to bees
A previously banned insecticide, which was approved for agricultural use last year in the United States, is harmful for bees and other beneficial insects that are crucial for agriculture, and a second pesticide in widespread use also harms these insects.

Native bees also facing novel pandemic
There is growing evidence that another ''pandemic'' has been infecting bees around the world for the past two decades, and is spreading: a fungal pathogen known as Nosema.

Bees grooming each other can boost colony immunity
Honeybees that specialise in grooming their nestmates (allogroomers) to ward off pests play a central role in the colony, finds a new UCL and University of Florence study published in Scientific Reports.

Microalgae food for honey bees
A microscopic algae ('microalgae') could provide a complete and sustainably sourced supplemental diet to boost the robustness of managed honey bees, according to research just published by Agricultural Research Service scientists in the journal Apidologie.

Bees point to new evolutionary answers
Evolutionary biology aims to explain how new species arise and evolve to occupy myriad niches -- but it is not a singular or simplistic story.

Quantifying objects: bees recognize that six is more than four
A new study at the University of Cologne proves that insects can perform basic numerical cognition tasks.

Prescribed burns benefit bees
Freshly burned longleaf pine forests have more than double the total number of bees and bee species than similar forests that have not burned in over 50 years, according to new research from North Carolina State University.

Insecticides are becoming more toxic to honey bees
Researchers discover that neonicotinoid seed treatments are driving a dramatic increase in insecticide toxicity in U.S. agricultural landscapes, despite evidence that these treatments have little to no benefit in many crops.

Neonicotinoids: Despite EU moratorium, bees still at risk
Since 2013, a European Union moratorium has restricted the application of three neonicotinoids to crops that attract bees because of the harmful effects they are deemed to have on these insects.

Bees 'surf' atop water
Ever see a bee stuck in a pool? He's surfing to escape.

Read More: Bees News and Bees Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.