Importing bees into South Africa, and the Capensis Problem. Mike Allsopp ARC-PPRI, Stellenbosch

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1 Importing bees into South Africa, and the Capensis Problem Mike Allsopp ARC-PPRI, Stellenbosch

2 European bees to Africa Unsubstantiated imports of European bees into South Africa in 1688 Later imports by Henry Barrington in 1868 (English bees) and Lord de Villiers in 1881 (Italian bees); many other imports around this time Imports banned in 1911 But many imports by the government of Italians and USA Midnites from Also into Zimbabwe from 1957 onwards, and many other parts of Africa

3 European bees to Africa Recent introduction of European bees into Africa in development programmes According to Fletcher, European bees in Africa were a total and utter failure ; could not adapt to local conditions Almost no trace of European mtdna or heterozygosity in malate dehydrogenase in South African bees little remains from European bees

4 The Capensis Problem Moving other bee populations to where bees are indigenous is never a good idea The Capensis Problem is an example of how bad things can go (and the African bees in the Americas?) A very real threat to beekeeping in Africa Almost impossible to eradicate

5 South African Honeybees Pretoria Kenhardt scutellata zone Nieuwoudtsville hybrid zone capensis zone Stellenbosch Cape Point Apis mellifera scutellata Savanna honeybee Apis mellifera capensis Cape honeybee

6 Pretoria Kenhardt scutellata zone Nieuwoudtsville capensis zone hybrid zone Cape Point Stellenbosch

7 Unique characteristics of capensis Rapid pheromonal development of workers Tergal glands in workers Worker pheromones very queen-like Physical dominance of workers pseudo-queens Large number of ovarioles Rapid development of ovaries Workers have a spematheca

8 Unique characteristics of capensis Capensis are not controlled by other queens Laying workers are able to inhibit other workers Thelytokous reproduction by workers (produce more workers or queens) Don t worker police Queen avoidance by parasitic workers Capensis worker-produced workers in colonies of other races are fed more, develop quicker, become pseudo-queens with enhanced reproductive features (super capensis) The most successful worker lineages dominate all reproduction Leads to just one or a few clones doing all the reproduction

9 Unique characteristics of capensis Ability to maintain viable clonal lineage for more than 20 years; maintain heterozygosity through reduced recombination and selection against homozygotes; because of life history as parasites Virgin capensis queens produce male and female eggs Social parasitism in the capensis population Capensis workers selectively parasitise queen cells, produce the next generation

10 Spread of capensis in South Africa: JOHANNESBURG SOUTH AFRICA DURBAN CAPE TOWN PORT ELIZABETH

11 The Capensis Problem

12 The Capensis Problem

13 The Capensis Problem

14 The Capensis Problem

15 Counter Measures Legislation Pay-out Information Research - Resistance - Chemical Control - Damage Limitation - Gave up

16 The Capensis Problem Today Effect increased by commercial beekeeping; large colonies; migration; pollination stress; extra manipulation but all of that is commercial beekeeping! Only current control method is to kill whole apiaries as soon as is detected, but commercial beekeepers are unable to do this Despite claims to the contrary; it has not been controlled; no solution as yet; situation as bad as ever; flares up in different areas Estimate 30% colony losses in commercial scutellata operations per year I hope to soon test some apiary control measures with may allow beekeepers to eliminate capensis from their populations

17 Cape Bees a Threat in Africa A commercial beekeeping problem; some small presence in the wild population but seems to have no effect; has not penetrated into large wild areas like nature reserves; and has not crossed SA borders But major threat to neighbouring countries; capensis infected colonies on the border of Zimbabwe, Swaziland, Botswana only takes a beekeeper in one of those countries to collect a capensis infected swarm, and it can be spread Don t take bees from South Africa

18 Cape Bees Diagnosis & Treatment Black bees in colonies Can be identified by dissection (ovariole numbers); or genetic analysis But best method is to make colonies hopelessly queenless and see if they produce worker brood No treatment at present; can be managed by eliminating all infected apiaries; spreading colonies out; keeping apiaries as discrete units But best not to get it Don t have bees moved in from outside, and watch for it every day

19 Phew! And it could have happened all over the world Probably restricted to warmer countries, but will survive in Southern Europe and Southern USA Taken to Brazil in 1957 Also Botswana, Russia, Germany, Netherlands and Poland, and probably others Not wise to play with capensis in other countries