The number of actors and measures for protecting the diversity of species is large – commitment of that kind has become a trend. One popular and widely accepted approach is supporting honey bees. Like every trend, however, this one too deserves a critical look. The question arises at what point a well-meant and apparently green solution contributes to ecological problems rather than solving them.
Photo: Andrena nitida is a widespread, unspecialised wild bee. The picture shows a male. (Photo: © Jürg Sommerhalder)
Support for honey bees and the loss of biodiversity
Besides commercial beekeepers, many private individuals keep bees today [1]. Companies [2][3][4] and political parties [5] also try to make their image greener with the help of the popular honey bee and therefore support projects to promote honey bees. In some places this causes the density of honey bees to rise rapidly, already reaching levels [6] that clearly have the potential to disturb the ecological balance – and thus to contribute to a further decline in the diversity of species [7] [8].
Competition
Experts have long feared that honey bees and wild bees might compete with one another. More and more studies therefore examine the effects of high honey bee densities on the local wild bee fauna. Many results indicate clearly that a high density of honey bees:
- leads to competition for food resources between honey bees and wild bees [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]
- displaces wild bees [10][11][12][13][20][22][23][24][25][26][27]
- can reduce the number and fitness of wild bee offspring [17][23][24][28][29] and
- encourages the transmission of diseases from honey bees to wild bees [19][30][31].
Already today almost half of the 616 [32][33] wild bee species recorded for Switzerland are considered threatened or extinct [34]. The long-term consequences of this decline can be extremely problematic: wild bees are among the most important animal pollinators of wild and cultivated plants [35][36]. They therefore count among the key species in terrestrial ecosystems and contribute substantially to the diversity of species [37][52][53].
Absence of regulation
Some cantons have already recognised the problem of the influence of high honey bee densities on the environment. In the nature reserves of the cantons of Bern [38] and Zurich [39], for example, permits are no longer granted for setting up honey bee apiaries. A regulation of this kind for the whole of Switzerland, however, is still awaited. And even in the two pioneering cantons named, sensible buffer zones for the effective protection of nature reserves are lacking: the flight radius of honey bees can be three kilometres and more [40]. It is therefore well above the diameter of most protected areas in the Canton of Zurich; despite the ban, these are thus in fact barely protected.
The highest honey bee densities today are reached in cities [41]. In the city of Zurich, according to the cantonal veterinary office, the number of beekeepers’ apiaries has risen by 80% since 2014 [42]. As zones free of pesticides, rich in structure and diverse in flowers, settled areas are important habitats and often show an impressive diversity of wild bees. Many rare and threatened wild bee species can be observed in cities [43] [44]. For this reason it seems particularly problematic that keeping honey bees in urban areas is regulated just as little as in classic zones with flora and fauna worth protecting.
Under current practice, honey bee apiaries and colonies need only be reported to the relevant veterinary office. That office does not check for any restrictions applying at the place concerned. Regulation according to quantitative and qualitative criteria is therefore absent [44]. Moreover, the duty to report is ignored by some beekeepers and not enforced by the authorities [45].
False perceptions, misleading campaigns and a lack of information
Keeping honey bees is understood as a measure to support biodiversity, and also as an important contribution to maintaining security of pollination and of food supply. Numerous studies show, however, that the part played by honey bees in pollinating wild and cultivated plants is mostly overestimated [46][47][48][49].
The highest agricultural yields are in fact achieved with the greatest possible diversity of natural pollinators [36][47]. Too high a density of honey bees therefore has a counterproductive effect in agricultural ecosystems as well, and thus economically [50][51].
Campaigns to promote honey bees that rest on scientifically untenable claims accordingly mislead the public, push effective measures for protecting the diversity of species and securing pollination into the background, and tie up valuable resources in projects that achieve little. Reticent or absent efforts to inform people further this development.
Making use of the potential
IG Wilde Biene is convinced that, through scientifically sound information, work to inform the public and targeted measures, a reversal of the trend towards an environment once again richer in species and healthier is possible.
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