Why Dark bees?

People sometimes ask why it is necessary to bring back the native Dark bee after the beekeeping community (in general) made the switch towards Carniolan and Buckfast bees on a large scale a few decades ago. The resurrection of the Dark bee is therefore sometimes seen as a problem rather than an enrichment. However, there are many facts arguing in her favor. The most important ones are discussed below.

Author: Dylan Elen, September 2019

Conservation of biodiversity

Climate change is a natural process that goes on as long as the earth has an atmosphere, sometimes the climate cools, sometimes it heats up. This time it warms up as a result of human activity (Hardy, 2005). Anyway, that too can be seen as a natural process. After all, humans ( Homo sapiens sapiens ) are just as natural a part of the Earth System as they are the Willow Willow (Salix caprea) and the Great Tit (Parus major).

So is it important that we now do our best to mitigate global warming? Why shouldn’t we just let the climate take its course and wait and see if it doesn’t find a new balance in the end? That’s how it has been for millions of years. Nevertheless, a significant proportion of the world’s population, including beekeepers, consider it important to intervene to halt current global warming.

The huge loss of biodiversity that has been recorded in recent decades, like current climate change, is mainly the result of human activity (Tilman, 2000; Clavero et al. , 2009; Krauss et al. , 2010 & Maskell et al. , 2010): deforestation in favor of agriculture, residential expansion zones, industrial area; toxicity due to water and air pollution from pesticide use and combustion products; spread of invasive exotic species due to globalization; 

Landscape fragmentation has a strong negative impact on biodiversity by breaking connectivity between areas (Groen Ravels)

Humans are to blame for this wave of extinction, which, due to the impact of the current global warming, which is also caused by us, may reach its peak. Anyone who is in favor of human intervention in limiting current global warming cannot really be opposed to human endeavors to save current biodiversity. After all, as the perpetrator we have a moral duty to help, in addition we need a liveable climate and a rich biodiversity to be able to live a good life ourselves in the future (Naeem et al .; 2016).

Everyone can decide for himself how he / she contributes to the limitation of further climate warming, as well as to that of the further loss of our biodiversity. In the case of beekeepers, the range of possibilities starts with the type of honeybee that they keep in their hives: native or exotic (assuming that the honeybee itself is native to the area at all). Moreover, this choice not only has an impact on the population of native honey bees themselves, as will be further explained.

Prevention of new bee diseases and parasites

Bee diseases (bacteria, viruses and fungi) and parasites (Varroa, Little box beetle) are easily spread through trade in bee material, bee colonies and queens. Parasites can sometimes be noticed by eye and then action can be taken in time, but with bacteria, viruses and fungi that is much less clear-cut. After all, anyone who buys queens cannot see which viruses or the like they carry. The problem only becomes apparent afterwards when it is laying in a hive and certain stressors, such as a food shortage, occur. However, then it is often too late.

Now many bee diseases are already present in the Low Countries, but new ones can always pop up as long as bees / queens are imported from everywhere. After all, bacteria and viruses quickly develop new strands. Think of the flu virus. Every autumn, elderly, young children and pregnant women are again advised to have the flu vaccine set, because the flu virus looks a little different every year and the antibodies built up by the previous year’s vaccine will therefore not work against this new variant. The same happens with bee viruses, in addition, sometimes there are also local variants. An additional problem here is that foreign disease variants are generally more virulent than the local disease variants, because there has never been co-evolution with the local honey bees. An example of this is Nosema ceranae1, which has also been present in Europe since 2005. In contrast to the local Nosema apis , the Nosema ceranae in our Western honey bees ( Apis mellifera ) is more virulent and deadlier (Martin-Hernandez et al .; 2011).

Nosema Tracks (Randy Oliver)

By purchasing queens from abroad or by traveling with queens to mating islands where dreamer lines from foreign growers are established (diseases can also spread through the sperm), substantial risks are therefore taken with regard to the introduction of new bee diseases. Moreover, that is not only a risk for the local beekeeping, but also for the solitary bees and bumblebees that occur with us. After all, it has already been demonstrated that many bee diseases are making the leap from honeybee to solitary bee and / or bumblebee as host, with all the negative consequences that entails (Tehel et al .; 2016). Beekeeping therefore has an important responsibility here.

The solution to limiting these risks is to work with the honey bees that are now present and to stop bringing in bee colonies / queens from elsewhere and traveling to mating islands with foreign drone lines. This strategy has already been included in the Flemish Beekeeping Program of 2017-2019, prepared by Honeybee Valley (Ghent University) in consultation with the Flemish beekeepers. The strategy, however, was part of realizing local adaptation (the importance of this is explained below) of the Flemish bee herd, but would also have been efficient with regard to the disease aspect. However, in practice that approach did not really get off the ground. After all, it presupposed the implementation of stand fertilization while the Flemish beekeeper does not like to just give up the “purity of the bees” of his bees, so it is often taught in beekeeping courses that purity is an important aspect of bees in order to have good peoples (although there are The Netherlands are sufficient beekeepers who prove the opposite with their “street bees”, and Buckfast bees in addition are a deliberately created hybrid of different subspecies). Also the idea that it is necessary to regularly get “new blood” (by importing queens or going to the islands), it is apparently difficult to get beekeepers out of their minds, yet it does not have to be necessary2.

The preservation of the indigenous Black bee, however, offers a logical alternative here: to preserve the Black bee, it is necessary to safeguard its genetic purity, given its indigenous character, mating positions should be established in this country, which is already closer to stand fertilization than to traveling to the Wadden (mating of queens about 30 km away from its apiary versus about 300 km). This will be discussed further in a subsequent article. The spread of bee diseases (new variants) would in any case also be strongly inhibited.

1 Note that N. ceranae is not a variant of N. apis , but a different species of Nosema . In other words, these are 2 variants of a common ancestor that have evolved separately over time.

2 In the current situation where positive selection is made (only further growing of the best performing bee colonies, eg growing 2 of 10 bee colonies), the genetic diversity within the population is constantly shrinking, so that the introduction of “new blood” Is necessary. However, one can also opt for negative selection (further cultivation of all bee colonies, with the exception of the worst performers, for example, growing 8 out of 10 bee colonies) where one does not have this necessity if a sufficiently large population is maintained (eg 200 – 250 peoples).

Less food competition for other pollinators

Due to the fact that Black bees, unlike Carnica and Buckfast bees, are only recently subjected to selection by beekeepers and that selection is often extensive in nature, a population of Black bees generally produces less honey than a population of Carnica or Buckfast bees . Where the latter can easily yield 50 to 60 kg per people on an annual basis (some lovers of these bees call even larger numbers), a Black bee population is more likely to yield 25 to 35 kg of honey. This is also partly due to the fact that a Black bees population remains smaller than a Carnica or Buckfast bee population. After all, it is known that bees from large bee colonies make longer flights and thereby collect more nectar than extract bees from small bee colonies, the value of nectar and pollen for a bee population is therefore dependent on the condition (size) of that bee population and individual workers fit there their foraging activities to. (Eckert et al. , 1994)

As a result, a Black bee colony will address the food sources in its environment to a lesser extent than a Carnica or Buckfast colony, with the result that it generates less food competition for other pollinators such as solitary bees, bumble bees, flies, etc. than the latter. This is because in some places other pollinators are seriously threatened by this honeybee food competition1, but in most places the severity of the situation is unknown to date (Mallinger et al .; 2017). Therefore, from the perspective of biodiversity conservation, it is important to use the prevention principle. That is, as long as it is not certain what the impact of that food competition is on other pollinators at a particular location, it is better to avoid the risk of a serious negative impact by keeping only a limited number of bee colonies at that location. The keeping of Black bees can thus fit within the prevention principle, unless, of course, instead of 6 Buckfast peoples, 12 Black peoples will suddenly be kept at that location, as a result of which the positive impact of keeping Black bees will be reduced to 0.

A Dark bee colony causes less food competition for other pollinators compared to a Carniolan or Buckfast bee colony. Photo: Orange-tailed Mining Bee (Jens D’haeseleer)

In the context of limiting food competition, it is of course important to also think on a larger scale. After all, the food competition is not exclusively determined by the number of bee colonies / type of honey bee of only 1 beekeeper, but by the number of bee colonies / type of honey bees of all beekeepers in the area (+ other factors such as the range of gestures, of course). That is why there is much to be said for the accurate mapping of the density of bee colonies. For example, it would be possible to determine in which areas serious food competition occurs for other pollinators and in which areas not. But also in the context of disease control in the event of an outbreak of, for example, American foulbroed, planning pregnancy improvement, … such a density map would find many applications.

1 Food competition can occur in different ways: in some cases, some species of solitary bees simply disappear from the area; in other cases, some species have a smaller number of offspring per individual; in yet other cases some species have smaller offspring; … Solitary bees were taken as an example here, but the concept naturally applies to all other pollinators that enter into a food competition with honey bees. For one species the negative consequences for the population are more serious than for the other, sometimes there are species that are hardly affected at first sight. The honeybee, at least the Black bee, is as native to the Low Countries as all the other 350 species of native bees, and food competition has always been there, but the current situation where there are easily 15 to 40 bee colonies in 1 location is indeed unnatural in comparison with the natural honey density of 1-3 bee colonies / km2. The gestation situation has also changed drastically over the decades.

Locally adapted honey bees have higher survival chances

From 2009 to 2012, RNSBB (Research Network for Sustainable Bee Breeding), which is part of the international research network COLOSS (Prevention of Honey Bee COlont LOSSes), conducted a pan-European study into the impact of the relationship between the genotype of honey bees and the environmental conditions in which those honey bees find themselves on the chances of survival of those honey bees. To this end, no fewer than 597 bee colonies were set up across 20 European bee stocks; for the experiment, queens of 16 different genotypes were used, all belonging to one of the following subspecies: Black bee ( Apis mellifera carnica ), Carnica ( Apis mellifera carnica ), Ligustica ( Apis mellifera ligustica ), Macedonica ( Apis mellifera macedonica ) or Sicula ( Apis mellifera sicula ). In this case, the concept of “genotype” can be presented as a local variant of the subspecies, for example, 3 different genotypes were used for Black: Black bees from Avignon (France), Black bees from Laesø (Denmark) and Black bees from Augustowska (Poland).

Sister populations of 3 to 4 different genotypes were set up at each of these experimental bee positions (at least 10 sister populations per genotype), including the local genotype. There was a series of sister populations of the genotype “Carnica Kirchhain (Germany)”1, a series of sister populations of the genotype “Carnica Kortowka (Poland)” and a series of sister populations of the genotype “Black” at Avignon (France). “ At the start of the experiment, all bee colonies were treated against Varroa so that every people could start the Varroa arm, and during the course of the experiment (October 2009 – March 2012), Varroa was no longer treated in order to fully reduce the impact of this stressor to be expressed in this survival experiment. If you treat bee colonies, you cannot test them for local adaptation.

Origin and distribution of genotypes (Büchler et al .; 2014)

At the end of the experiment the mortality of the local genotype was calculated for each apiary versus the mortality of the non-local genotypes, the same was done for all apes combined. The result was unequivocal: regardless of the apiary, the local genotype showed significantly higher chances of survival than the non-local genotypes. When we return to the Kirchhain stand, “Carnica Kirchhain” showed significantly higher chances of survival than “Carnica Kortowka” and “Black at Avignon”. In other words, of all three genotypes, “Carnica Kirchhain” died the least in Kirchhain. The existence of genotype x environment interactions with honey bees, as well as the impact of this on their survival, was thus demonstrated for the first time in black and white. The message from the European Research Panel to Beekeeping was therefore to give preference to local honey bees. (Büchler et al .; 2014 & Francis et al .; 2014)

Chances of survival of local and non-local genotypes, without treatment against the varroa mite (Büchler et al .; 2014)

Some beekeepers sometimes ask why Black bees should be kept if the climate changes so much. The previous experiment was carried out from 2009 to 2012, a period in which the effects of the current climate warming were already taking full advantage. Nevertheless, the local genotypes still showed significantly higher chances of survival. This indicates that it is definitely worth keeping up with our Black. Moreover, the Black bee occurs naturally from southern France to Scandinavia and from the British Isles to the Ural Mountains, and also occurs in Tasmania and New Caledonia as artifacts of colonization by Western Europeans. This shows that the Black bee has a very strong adaptability and that our native honey breakfast will therefore probably also be able to adapt to the challenges that are now facing it.

1 You see that locally adapted honey bees do not necessarily have to be native honey bees. After decades of selection within a closed population, the Kirchhain bee institute has established a Carnica line that is adapted to local environmental conditions. Although Carnica and Buckfast have been cultivated in Belgium since the 1970s, there may not be a locally adapted Carnica line or Buckfast line according to Belgian standards because a closed population concept was never used, but instead there has always been / will be traveled to mating islands and queens are still being imported from abroad every year. The genetics of Carnica and Buckfast bees in Belgium therefore never have the chance to adapt to local environmental conditions. This is somewhat different for the Black Bee, as there is still a remaining population in Chimay.

BUT, the Dark bee is not the “best bee”

As a rule, every beekeeper believes that the type of honeybee with which he / she is beekeeping is also the best type of honeybee. That claim is completely legitimate, because the use of terms such as good, better, bad, horrible, … is often entirely subjective and dependent on the perspective from which one looks at reality. If 10 people are sent to the bakery and they are asked to bring the “best” bread, they will come back with different breads. Some will have brought a dark loaf because they judge from a health perspective and a dark loaf is healthier than a white loaf; others will have brought a white bread because they judge from the perspective of taste and they simply prefer white bread; others will have brought the cheapest bread because they judge from the perspective of economy; And so on. The same concept also applies when beekeepers judge which type of honey bee they think is best: a beekeeper who judges from the perspective of honey yields will find Buckfast bees best because they often produce the largest amount of honey per people; a beekeeper who judges from the perspective of nature conservation and sustainability will again find Black bees the best.

Just like you buy bread according to your own choice and taste, you keep bees according to your own preferences and convictions

No judgment, no perspective is essentially wrong, because the decision-making process of the beekeeper about the basis on which he will judge (the perspective) is entirely subjective. It is important that this information is understood and accepted by the beekeeping company. Respecting each other’s perspectives has, up to now, sometimes been a serious problem, which can lead to unnecessary tensions. In some cases, unfortunately, this is due to a lack of knowledge, for example when beekeepers think that Black bees are aggressive by definition, while it has long been known that gentle Black bees have also been produced through selection. The distribution of correct and updated knowledge is therefore quite a priority for beekeeping organizations.

The Black bee will therefore certainly not be “the best type of honey bee” for every beekeeper, and that in itself is no problem. But for those who care about nature and sustainability, like to look at the survival of honey bees from a scientific perspective and just think it’s important that their bee colonies are gentle and can be extensively managed, it might be worth considering our Black bee . Anyway, now that we have seen why it is important to keep up with the Black, we will start next time with how this should be tackled in practice.

References

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