Violence against Bees (VAB)
Evidence of VAB
In the United States it is common to lose a large number of colonies every year. For example, in northeastern USA, where only 18.9% of beekeepers collect swarms to start new hives, it is not atypical for beekeepers to lose a third of their hives (Department of Agriculture, Conservation, and Forestry, 2020). In the European Union, based on more than 8,500 visits to apiaries, a survey reported wide variation in annual mortality, ranging from 3.5% in Lithuania to 33.6% in Belgium (Cressey, 2014). Likewise, in China considerable variations in annual total colony losses are found among provinces (ranging from 0.9% to 22.0%) (Tang et al, 2020). There are large variations even within geographical regions.
Traditional beekeepers in Tanzania usually use fire instead of smoke to control bees during harvesting, and all combs – honey, brood, and pollen – are removed from the hive. This harvesting practice disturbs the colony and if it is not destroyed will usually abscond or migrate.
Causes
of VAB
Why do bees become susceptible to disease and death in one area but not so much in a place nearby. The reasons for the failures of so many bee colonies in North America, Europe, and China were attributed to poor over-wintering conditions, Varroa mites/viruses, environmental factors, and queen loss/failure, and unknown reasons. Much of the stress is certainly due to the prevalent use of pesticides and herbicides in Europe and North America, and increasing use in Africa.
Additional
stress is felt Apis mellifera spp.in North America, because it is not
native. This species was brought to North America and has gained traction with
the reign of non-native plants also from Eurasia, which have inundated North
America. Apis mellifera are industrialized to pollinate crops which
are also non-native, such as almonds and apples. Commonly queens are imported from
other places with and without nucleus colonies. In addition, these bees may be displacing
native bees, which could be labelled as another type of violence: VAB by B.It seems this could happen in early spring. In Vermont honey bees that
have overwintered well, have known to emerge from the hive before pollen is
available. They will be fed sugar water at this time, and will be well on their
way to displacing later emerging native bees who are more closely attuned to
the flowering times.
In Tanzania and much of Africa the problems are different. Fortunately, in Tanzania the most productive honey bee, Apis mellifera scutellata is native and evolved with its current surroundings. The Varroa mites plaguing honey bees in North America and Europe do not seem to be a problem in Africa. In un-pesticided areas, it is common to have almost all hives filled by swarms of native honey bees that moved in freely within weeks. This is an economic advantage for Tanzanian beekeepers.
However, their equipment is poor. The hives are often very fragile made of bark. Top bar hives would allow the beekeeper to check if the combs are ready for harvesting, without harming the bees. This practice encourages leaving the brood, and taking only the honey.
Traditional honey harvesters and beekeepers do not have bee suits, so even though they wrap themselves with scarfs and sweaters, they typically are inflicted with many wounds. One traditional beekeeper said that after harvesting he would go to bed for several days. Bee suits will protect the harvesters; since they don’t need to fear being stung, they remain calm.
They
don’t have smokers, so they brandish fire. Smokers can be used to dull the bees without
the
danger of fire killing them.
Possibilities
of Ethical, Humane Bee-Human partnership in Tanzania
Adult honey bees are well known to exhibit collective nest defense against mammalian predators and robber bees from other colonies (Rittschof et al., 2015). Stinging is not a preferred method of defense because when the stinger sticks into the human it pulls out from the bee, resulting in its death. The rapid defensive response of the bees is socially coordinated by pheromone cues. African honey bees have a reputation as being extra aggressive.
Recent research suggests this hyper-aggression may be localized. And may be a result of traditional honey harvesters perceiving a ‘war’ between themselves and the bees for what they all prize, the honey, and the bees reacting to that threat to their nest.
It has been learned that aggression is also socially modulated over longer time scales allowing colonies to adjust their behavior in response to local ecological conditions (Rittschof et al., 2015). I have had such an experience with African honey bees in my garden in Dar es Salaam. When bees first moved in they were very aggressive - several times chasing me into the street. But over time they built long oval combs in a low-lying branch of a tree near a garden path –bothering nobody for seven years - only leaving when a passion vine clambered over the tree and made it too damp for them underneath. They moved into the roof and we have continued to live together for more than a decade without any stinging or threatening behavior.
We expect that with increased training, suitable hives, suitable tools (such as smokers), and bee suits it is likely that VAB will be dramatically reduced.
References
Cressey, D.(09 April 2014) EU states lose up to one-third of honeybees per year. Nature | News https://www.nature.com/news/eu-states-lose-up-to-one-third-of-honeybees-per-year-1.15016
Department of Agriculture, Conservation, and Forestry. State of Maine, USA. 2019/2020 Maine Honeybee Survey. Accessed at : https://www1.maine.gov/DACF/php/apiary/documents/2019-2020-bee-survey-summary.pdf
Rittschof, C C et al. (2015). Early-life experience affects honey bee aggression and resilience to immune challenge. Sci. Rep. 5, 15572; doi: 10.1038/srep15572.
Tang J, Ma C, Shi W, Chen X, Liu Z, Wang H, Chen C.(2020) A National Survey of Managed Honey Bee Colony Winter Losses (Apis mellifera) in China (2013–2017). Diversity; 12(9):318. https://doi.org/10.3390/d12090318).
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