colony losses: fact or fiction? h. human, r. crewe and c. pirk

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%– 1915- 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

Country Losses

Algeria 13.45Austria 17.2Bosnia & Herzegovina 6.18Croatia 9.52Denmark 20.91Estonia 25.53Finland 17.02Germany 15.39Ireland 37.08Israel 5.9Italy (Veneto region) 12.2Latvia 19.65Netherlands 13.71Norway 18.15Poland 18.11Scotland 31.06Slovakia 9.13Sweden 22.62 losses 31% (USA) & 34% (UK)

Honey Bee Colony Losses Winter 2012-13

• “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 coloniesDo 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 # ColoniesAbsconding 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

RESULTSBiggest problem is the return rate

– 2013 data from 19 European countries• 15 000 beekeepers & 280 000 colonies

– USA • 6 287 beekeepers managing 599 610 colonies (23%)

– RSA for both seasons • 95 beekeepers & 23 355 colonies (4%)

http://www.southafrica.to/provinces/RSA_by_provinces.jpg

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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:•romee.van.der.zee@beemonitoring.org •US http://beeinformed.org/2013/05/winter-loss-survey-2012-2013

•UK http://www.bbka.org.uk/files/pressreleases/bbka_release_winter_survival_survey_13_june_2013_1371062171