Colony losses: fact or fiction? H. Human, R. Crewe and C. Pirk
Global decline in honey bee numbers – great concern – received attention Exceptional colony losses not unusual Multiple records over 100 years – early 1900s Isle of Wight - 90% – 1910 Australia - 59% – USA & Canada – 2002/03 Sweden & Germany – 2006/07 USA No definite cause, only speculation An event or part of disappearance cycle? Fact or fiction?
Working Group Monitoring and Diagnosis - investigating colony losses Standardised protocol for collecting data - allow for comparisons COLOSS Network Monitoring & Diagnosis Pests & Pathogens
CountryLosses Algeria13.45 Austria17.2 Bosnia & Herzegovina6.18 Croatia9.52 Denmark20.91 Estonia25.53 Finland17.02 Germany15.39 Ireland37.08 Israel5.9 Italy (Veneto region)12.2 Latvia19.65 Netherlands13.71 Norway18.15 Poland18.11 Scotland31.06 Slovakia9.13 Sweden22.62 losses 31% (USA) & 34% (UK) Honey Bee Colony Losses Winter
“Losses remain greater than beekeepers consider acceptable” (2013 COLOSS press release) Explanations remain elusive Several possible causative factors: both alone and in combination – pesticides, – pests and diseases, – poor nutrition, – beekeeping management practices Global perspective
Large wild population -310 million colonies, small proportion managed Two subspecies – Apis mellifera capensis – Apis mellifera scutellata All major honey bee diseases & parasites present – Varroa mites – American foulbrood – Capensis problem (outside native range, social parasites) South African situation
2011/2012 Questionnaire: Colony losses in South Africa Limited knowledge about colony losses Questionnaire developed over 3 years, 20 countries Aim of questionnaires: quantify colony losses identify potential causes & threats collect comparable data - standardised protocol data contributes to international picture
3. Which of the following reasons would you give for your colony losses? How many colonies were lost to this reason? 4. Wild/ Feral colonies Do you know of any wild colonies in your area, if yes how long have they been present at this site? Please give years and if possible GPS coordinates. Yes/ No# Colonies Absconding Bad beekeeping Bad weather / lack of forage/ drought Capensis bees Diseases Fire Honey badger / ants Insecticides / poisoning Pollination stress Small hive beetles Vandalism / theft Country specific situation
RESULTS Biggest problem is the return rate – 2013 data from 19 European countries beekeepers & colonies – USA beekeepers managing colonies (23%) – RSA for both seasons 95 beekeepers & colonies (4%)
Questionnaires: Average colony losses Losses Scutellata (29.1%) > Capensis (17.9%)
Effect of migrating (combined data) Only significant for A. m. scutellata, not for A. m. capensis
Crop effects No significant differences between losses
Losses significantly higher when pollinating these crops
Perceived causes small hive beetle, Varroa, absconding (loss to beekeepers not bee population), chalkbrood Capensis social parasite
Capensis Remains a major problem in Scutellata areas – good beekeeping practices NB – problem in the Cape to a lesser degree? Increasing number of colony losses ? Is it wise to consider the wild bee population as an inexhaustible resource for restocking ?
Conclusion African honey bee population is affected by – same factors as bee populations elsewhere – Africa- specific problems Losses in both years higher than what is globally acceptable - contradicting to FAO reports RSA losses to beekeepers not bee population Is it threatening businesses? All stakeholders NEED MORE INFORMATION
PLEASE FILL IN OUR QUESTIONNAIRES? Questionnaire Results will be published in JAR All participants will be updated
Acknowledgements SIRG SABIO Beekeepers Dr Dennis vanEngelsdorp DST, NRF, UP & COLOSS for funding
Information on losses: US UK survey_13_june_2013_ survey_13_june_2013_