Honey bee colony losses continue in the USA

publication date: Feb 25, 2011
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The world's longest established apicultural research publishers

 Press Release


Honey bee colony losses continue in the USA

IBRA has now published the 2009-10 winter survey of USA honey bee losses which shows the fourth consecutive year of high mortality in a study by Dennis vanEngelsdorp and colleagues.

This study compares colony losses and the reasons why beekeepers believe their bees died for "backyard beekeepers (those keeping under 50 colonies) "sideline beekeepers (those keeping between 50 and 500 colonies, and commercial beekeepers who maintain in excess of 500 colonies. 

Over the winter of 2009-10 US beekeepers responding to the survey lost an average of 42.2% of their colonies. Perhaps counter intuitively, backyard and sideline beekeepers reported higher losses than commercial beekeepers, although the commercial beekeepers were more likely to report losses due to Colony Collapse Disorder ("CCD") where the colony has died yet the hive contains no dead bees.

All beekeepers said that the parasitic mite Varroa was a major problem.  Commercial beekeepers said the mite was the second important factor for causing bee losses.  Overall, manageable conditions such as starvation and colonies being weak before overwintering were attributed as the leading causes of bee losses.  In contrast, commercial beekeepers ranked the reasons for their losses as poor queens, mites, pesticides and CCD. More effort into understanding the underlying causes of these losses is needed. 

In order to aid understanding, IBRA's major international Conference "Varroa - still a problem in the 21st Century?" will be held on 29 January 2011 at the University of Worcester. 


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Norman Carreck, Scientific Director, IBRA +44 (0)791 8670169 Email: norman.carreck@btinternet.com


Sarah Jones, Executive Director IBRA Tel:+44 (0)29 2037 2409 Email: jonessl@ibra.org.uk


Notes for editors:-

1. The paper: "A Survey of managed honey bee colony losses in the U.S., fall 2009 to winter 2010" by Dennis vanEngelsdorp, Jerry Hayes Jr., Robyn Underwood, Dewey Caron, and Jeff Pettis is available to download free of charge online at:-


2. The full Programme of the Conference "Varroa - still a problem in the 21st century?" is available at:-www.ibra.org.uk

3. The International Bee Research Association ("IBRA") is the world's longest established apicultural research publishers and promotes the value of bees by providing information on bee science and beekeeping worldwide. 

4. IBRA is a Registered Charity, and its Council of trustees boasts some of the world's leading bee scientists. 

5. IBRA publishes the following peer reviewed scientific journals: -

5.1 The Journal of Apicultural Research was founded by IBRA in 1962.  It includes original research articles, theoretical papers; scientific notes and comments; together with authoritative reviews on scientific aspects of the biology, ecology, natural history and culture of all types of bee.

5.2 The Journal of ApiProduct and Apimedical Science was launched by IBRA in 2009.  It focuses upon evidence based research being carried out on biologically relevant properties of bee and hive products, and their scientific relevance in the fields of medicine, nutrition and healthcare.  This journal provides a forum where the efficacy and effectiveness of bee and hive products with therapeutic properties can be presented, debated and evaluated using scientific principles.

6. IBRA publishes and sells books on bee science and beekeeping. 

7. IBRA also provides bee information services. 

8. Membership of IBRA costs just £31.50 annually.  Membership benefits include receipt of four quarterly issues of Bee World, an accessible and topical journal on latest bee research, news, reviews and other relevant information for the bee scientist, beekeeper, and anyone with an interest in bees. 

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