Our directory of things of interest

University Directory

US loses honey bee colonies

A dead honey bee showing many details of body, legs and mouth parts. Apis mellifera A dead honey bee showing many details of body, legs and mouth parts. Apis mellifera Armando Frazao
15 May
2015
Winter beehive losses are down over the previous year, but April 2014 to April 2015 saw an increase in summer losses too. It’s a change over previous patterns, and the cause is still a mystery

US bee-keepers lost 40 per cent of their honey bee colonies between April 2014 and April 2015. Winter losses improved over previous years, but summer losses made up for the reduction.

Commercial bee-keepers were badly hit, with summer losses higher than winter losses for the first time in five years.

‘We traditionally thought of winter losses as a more important indicator of health, because surviving the cold winter months is a crucial test for any bee colony,’ says Dennis van Engelsdorp, an assistant professor of entomology at the University of Maryland and project director for the Bee Informed Partnership.

‘But we now know that summer loss rates are significant too. This is especially so for commercial bee-keepers, who are now losing more colonies in the summertime compared to the winter. Years ago, this was unheard of,’ he adds.

The 6,000 bee-keepers who took the survey – now in its ninth year – reported 42.1 per cent of colonies were lost over the year. Winter losses fell from 23.7 per cent to 23 per cent, while summer loss rates increased from 19.8 per cent to 27.4 per cent.

The survey covered nearly 15 per cent of the country’s 2.74 million managed bee colonies.

150513093605 1 900x600Bee loss rates for 2014 to 2015. (Image: USDA)

For amateur bee-keepers – defined as those managing less than 50 colonies – the varroa mite is thought to be to a major factor, but the cause in most cases is unclear.

‘Backyard bee-keepers were more prone to heavy mite infestations, but we believe that is because a majority of them are not taking appropriate steps to control mites,’ says van Engelsdorp. ‘Commercial keepers were particularly prone to summer losses. But they typically take more aggressive action against varroa mites, so there must be other factors at play.’

The survey is part of a wider study into why honey bee colonies are in poor health. Valuable crops, such as almonds, depend on honey bees for pollination. Honey bee pollination contributes between $10billion and $15billion to the US agricultural economy annually.

‘The winter loss numbers are more hopeful especially combined with the fact that we have not seen much sign of Colony Collapse Disorder (CCD) for several years, but such high colony losses in the summer and year-round remain very troubling,’ says Jeffery Pettis, a senior entomologist at U.S. Department of Agriculture and a co-coordinator of the survey. ‘If bee-keepers are going to meet the growing demand for pollination services, researchers need to find better answers to the host of stresses that lead to both winter and summer colony losses.’

Related items

Subscribe and Save!

geo line break v3

Free eBooks - Geographical Newsletter

Sign up for our weekly newsletter today and get a FREE eBook collection!

geo line break v3

University of Winchester

geo line break v3

EDUCATION PARTNERS

Aberystwyth University University of Greenwich The University of Derby

TRAVEL PARTNERS

Ponant

Silversea

Travel the Unknown

NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in NATURE...

Oceans

A ship that ran aground early in February has been…

Wildlife

Two whale populations on either side of the African continent…

Geophoto

March traditionally heralds the beginning of spring, a time of…

Wildlife

An innovative project to utilise Laos’ elephant experts in service…

Polar

Despite common belief that Antarctica is vastly uninhabited, humans are…

Wildlife

Javan rhinos survived the recent Krakatoa tsunami, but the species…

Energy

As the world turns away from fossil fuels, one question…

Geophoto

The winners of the Outdoor Photographer of the Year 2018…

Climate

New legislation in Florida aims to solve various environmental issues,…

Polar

The world’s magnetic model is getting an early update, as…

Climate

Marco Magrini looks at the financial pressures spilling out into the…

Geophoto

Few sights are more dramatic than a star-filled sky at…

Polar

A region of Antarctica previously known for relative stability is…

Tectonics

Everything we thought we knew about eruptions could be wrong

Oceans

Sea levels are rising across the globe, but along the…

Polar

Seismometers buried in the Ross Ice Shelf have revealed that…

Wildlife

A tightening of restrictions on the insecticides known as neonicotinoids…

Wildlife

Bonnethead sharks, the second smallest member of the hammerhead family,…

Nature

There’s more than enough plastic in the world. That’s why,…

Wildlife

The recent discovery of more than 200 million termite mounds…