Tree bumblebee ( Bombus hypnorum )
|Latreille , 1802|
The bumblebees ( bombus ) are a genus of state-forming insects belonging to the real bees . The in females over a military sting enacting Hymenoptera (Hymenoptera) are among the aculeata , also called Wehrimmen. They occur predominantly in the more moderate and cooler regions of the northern hemisphere .
A bumblebee colony consists of around 50 to 600 animals and a queen , depending on the species . The majority of the animals are workers , and the colony also includes males, who, like honey bees , are called drones , and young queens. A people in Europe only survive one summer and usually died in September. Only the mated young queens overwinter, who in the early spring of the next year, left to their own devices, begin building a nest and thus founding a new state. Such queens reach an age of up to twelve months, of which they spend up to eight months in hibernation. Drones and workers, on the other hand, usually only reach an age of three to four weeks.
While honey bees only fly out at an outside temperature of at least 10 ° C, bumblebees queens can be observed in early spring from 2 ° C and bumblebee workers from 6 ° C, as they generate the body temperature necessary for flying by vibrating the chest muscles.
Bumblebees have been used as pollinator insects in the commercial cultivation of fruits and vegetables since the late 1980s. Their use in the greenhouse cultivation of tomatoes is of great economic importance. Millions of bumblebees' nests are artificially raised and sent to vegetable farmers around the world every year. The most important species is the dark bumblebee .
The strong, rounded oval body consists of three sections: the head , the thorax and the abdomen . It is covered in fur-like hair, which protects it from the cold, and also has multi-colored stripes. This coloring comes in different ways z. B. with the field bumblebee and the stone bumblebee , while the dark bumblebee and the garden bumblebee have a white abdomen tip and are very similar. Often bumblebees can be seen that have bald, shiny spots on the body near the head. Hair loss occurs when the entrance hole to the nest is so narrow that when entering and exiting the nest, the areas concerned have contact with the edge of the loophole.
Bumblebees have a proboscis for feeding, which varies in length depending on the species. The average length for queens is approx. 13 mm, for workers approx. 12 mm and for drones approx. 10 mm. There are pairs of feelers , compound eyes and transparent wings as well as 6 multi-part legs.
The queens are between 15 and 23 mm long, depending on the species, with a wingspan of 18 to 43 mm, the workers and drones are 8-21 mm long and have a wingspan of 18 to 34 mm. The size also varies within the respective species, both for drones and workers.
Distribution and types
There are around 250 species of bumblebee, mostly found in the more temperate and cooler regions of the northern hemisphere. The bumblebees are particularly species-rich in Europe and Asia , they inhabit practically the entire Eurasian land area north of the Himalayas. They are absent in Africa south of the Sahara and in Australia , in India they are only found above 1000 m, a few species inhabit the mountains of Taiwan , Java and Sumatra . In warmer regions, bumblebees are largely restricted to mountains, including in America , where they are distributed in comparatively few species as far as Tierra del Fuego . However, there are also individual species that colonize the Amazon basin .
European bumblebee species
There are around 70 species in Europe, 36 of which are found in Germany. There are currently 16 species of bumblebee on the “Red List” of threatened species in Germany (for a list, see web links ). In some regions, e.g. B. in North Rhine-Westphalia , some species are already extinct. Besides hornets and wild bees, bumblebees are protected by the Federal Nature Conservation Act in Germany, and there are similar protective provisions in many other countries. Overall, the following bumblebee species are represented in Europe (sorted by scientific name):
The list of bumblebee species names all known bumblebee species worldwide.
Cuckoo or parasite bumblebees
Socially parasitic species, so-called cuckoo or parasite bumblebees, nest in the nests of bumblebee colonies in order to allow their offspring to be raised by the inhabitants. There are no workers in these species. There are ten such species, six of them in Germany such as B. the four-colored cuckoo bumblebee . They were often considered a separate genus Psithyrus in the past .
The parasites eat the people's eggs and try to lay their own. If this succeeds, the offspring of the social parasites displaces those of the host, and fewer queens develop.
Naturalization in New Zealand
Bumblebees were naturalized in New Zealand in the 19th century. Farmers there struggled with the problem that the red clover applied had little or no seed, forcing them to keep importing seeds from Great Britain. A hobby entomologist finally noticed that bumblebees were missing in New Zealand and that this was the reason for the non-seeding red clover. The first attempts to introduce bumblebees failed because it was not possible to transport the bumblebees alive across the equator by ship. This only succeeded in 1885: 282 hibernating young queens had been collected in Great Britain and placed in the cold store of the Tongariro , one of the first steamships with such a facility, in December 1884 . When the ship docked in Christchurch on January 8, 1885 , 48 of the bumblebee queens were still alive. The Aorangi , a sister ship of the Tongariro , brought another 49 living bumblebee queens to New Zealand a month later. The released bumblebee queens immediately reproduced very successfully in New Zealand. As early as 1886, bumblebees were sighted 100 miles south of Christchurch, and by 1892 bumblebees were so common that beekeepers were concerned about food competition from their bees.
The species composition of the introduced bumblebees is unknown. Today, however, the dark bumblebee, the garden bumblebee, the field bumblebee and, more rarely, the earth bumblebee can be found in New Zealand .
Within the bees, the bumblebees belong to the group of cup collectors , a monophyletic group that includes honey bees . The phylogenetic structure within the group has not yet been satisfactorily clarified, so according to the current state of research it cannot be said which is the sister group of the bumblebees.
The bumblebees themselves are divided into a number of around 35 subgenera, but it is difficult to distinguish them from one another because the bumblebees have a very uniform body structure. The cuckoo bumblebees of the subgenus Psithyrus have been split off as a separate genus by many authors . Phylogenetic studies indicate, however, that deviations in the body structure of the cuckoo bumblebees are only to be interpreted as adaptations to the way of life, psithyrus apparently does not form a sister group to the other bumblebees, as can be seen from the following cladogram :
The attempt to split the genus Bombus into several monophyletic genera in order to raise Psithyrus to the genus rank is generally considered unsatisfactory because of the uniformity of the entire group. Since some parasitic bumblebee species are also known outside of Psithyrus , most authors now consider Psithyrus only as a subgenus.
The bumblebee's nest over the course of the year
The mated young queens who survive the hibernation will found a new colony on their own next year. To do this, you first look for a suitable place for the nest in early spring . Depending on the species, the nesting site can be a small cave in the ground such as a mouse hole (earth bumblebee), a layer of moss or a hollow tree trunk. Tree bumblebees also nest in abandoned bird nests. The nests are usually only used for one year. Very rarely does a queen return to the nest in which she herself grew up. Unlike in the temperate climate zones, there are perennial bumblebee colonies in the tropics .
The queen collects nectar and pollen , which she processes into so-called “ bee bread ”, on which she lays the first eggs in a “cell” made of wax . The queen and later also the workers excrete the wax for the cells from the abdomen. As a source of food for herself, the larvae and the hatched bumblebees, the queen also builds a small "pot" which she fills with honey . The potty is often positioned near the eggs. The eggs keep warm, the queen is laying eggs after the first if necessary to brooding on it, and her head is often facing the honey pot. In this way, she can pick up honey with her trunk at any time without having to leave the eggs to eat. The cell arrangement is loosely grouped in an upright heap in the shape of an urn or jug. Around the brood area there is an insulating cover made of grass , hair and moss , which is glued with wax or honey. The nest is often sealed against heat loss with a layer of wax, which is regularly renewed and repaired.
Temperatures of up to 38 ° C can be reached during incubation. The constant nest temperature is around 30–33 ° C. During the first ten days, the brood goes through various larval stages in which they resemble small maggots . The queen bites small openings in the brood cells and feeds the larvae for up to ten days. They pupate then be butterflies similar and hatch after a ten-day metamorphosis as bumblebees with wings. During this metamorphosis, the queen lays eggs a second time and leaves the nest for a few more times to collect food again. The hatching bumblebees are exclusively workers. They initially stay in the nest for a few days, warming and feeding the next generation of larvae. They then begin to leave the nest for the first time to collect food. At this point, the bumblebee queen stops her feeding flights and remains in the bumblebee's nest until the end of her life. From then on she lives only on the food that is brought in by the workers.
In Central Europe, a bumblebee queen permanently secretes a pheromone in the nest from the first egg-laying until around July , which ensures that only workers develop in the colony. From July onwards, the queen stops secreting pheromones and lays both male and female eggs. Due to the lack of pheromones, young queens develop from the female eggs. One hundred or more young queens and several hundred drones can grow in a single large colony of bumblebees. These new males and females spend a few days in the nest and then leave the nest forever.
The old queen, who is now about a year old, remains in the nest. Since no more workers grow up, food runs out as the colony workers die. The old nest died around September.
|egg||3.5 days||3.5 days||3.5 days|
|larva||7.3 days||10.5 days||10.0 days|
|Doll||9.4 days||13.2 days||11.0 days|
|Total duration||20.2 days||27.2 days||24.5 days|
Mating of the young queens
Drones have no other function than mating with a young queen. They only survive a few weeks and can be seen more frequently than other bumblebees in midsummer, preferring to drink nectar from large-flowered flowers. In most bumblebee species, the queens only mate once, while the drones are quite capable of mating multiple times. It is therefore unclear why bumblebee colonies raise so many more drones than young queens. Most bumblebee species grow seven times as many males as young queens.
While mating bumblebees are occasionally observed, it is still largely unclear how drones and young queens find each other. Light-colored bumblebees may pursue a summit courtship , as groups of males of this species can be found in the hilltop area. Summit balz (sometimes also called "hilltopping" according to the English technical term) is a behavior in which males seek out certain exposed areas in the area, such as hill tops or mountain tops. They try to occupy an area as high up as possible against the horizon and to displace rivals. Females ready to mate then fly to such locations to meet males there.
In the case of other bumblebee species, males can be observed to fly certain routes in a targeted and regular manner. This behavior has already been described by Charles Darwin . He had noticed in his garden in Kent that garden bumblebees flew certain distances along hedges and moats every few seconds. In addition to garden bumblebees, this behavior has now also been described for the dark bumblebee and the stone bumblebee . Scandinavian scientists were able to prove that the drones of the individual species differ in their altitude. Stone bumblebees patrol along certain routes at treetop height, while garden bumblebees prefer to fly near the ground. What they all have in common is that the drones start their patrol flights early in the morning and leave pheromones every five to 10 meters on a branch or leaf. The drones then pause briefly in their flight at these points. The marking points of the individual males differ slightly from one another, but they follow a common route that is typically 200 to 300 meters long. Since the drones are fast fliers, the route is flown by a single male every few minutes. It is believed that the pheromones attract the young queens, so that the males patrolling here have the greatest chance of mating. Another unexplained phenomenon of bumblebee behavior is the way in which the males synchronize the route to be taken with each other and why males use the same patrol routes repeatedly over the years, even though each generation of males dies in autumn. The entomologist Dave Goulson suspects that either traces of pheromones remain or that the route has certain scenic features that make it particularly suitable for such patrol flights.
Drones from other bumblebee species gather in the immediate vicinity of a nest exit in an attempt to meet young queens. In the case of moss bumblebees , such a group of males was examined for their degree of relationship to one another and to the nest in front of which they were located. The DNA samples showed that males were neither from the nest in front of which they had gathered, nor that most of the assembled drones were related to one another. So far, one can only guess that the males found the nest in question through the smell.
Shortly after mating, which in Central Europe sometimes takes place in June, but mostly in July and August, young queens look for a suitable place to hibernate. Unlike the males, they can therefore only be observed very rarely. Typical winter spots for the young queens are old compost heaps and molehills. It is unclear why they start wintering so early, although there is still enough food available at this point in time.
Foraging and Pollination
A distinction must be made between the collective flight distance and the maximum distance. Both are species-specific and can be determined by pollen analyzes. This results in average flight distances of 180 m to 1,250 meters. The maximum distances are estimated at 300–1,500 m. The body size plays a decisive role and small species (less than 10 mm in length) generally only fly 100–300 m. Larger species (over 15 mm in length) can manage 600–1,200 m. The transport capacity has a decisive influence on the distance to be achieved, because the more pollen the leg or belly brush can absorb, the further a female bumblebee can fly. In addition, there are clear individual differences in the willingness of the animals to fly to fodder plants that are further away. For most females, shorter distances are preferred.
Investigations on marked bumblebees have shown up to 1750 meters in some bumblebee species. In contrast, a large species of wood bees can manage about six kilometers.
Importance as a pollinator insect
Along with honey bees and flies, bumblebees are among the most important pollinating insects . Their insensitivity to temperature enables bumblebees to forage for food much longer than other bees. Bumblebees fly to up to 1000 flowers every day in up to 18 hours in search of food, rarely more than two different types of flowers per flight. Some plant species, for example dead nettles , are only pollinated by long-nosed bumblebees when nectar is extracted. They also pollinate many types of fruit, among others .
In contrast to bees, bumblebees fly to flowers even in bad weather in order to ensure the survival of their colony, as their food supplies are smaller than those of the bees. They feed on pollen and nectar , the workers cover their extremely high energy needs with nectar. The ability to ensure pollination even in wet summers and the low temperature sensitivity compared to bees make them important helpers for many types of plants, including many types of fruit and vegetables, especially in rainy summers with low average temperatures . Nectar is stored in barrels near the nest entrance, there are two different behaviors when storing pollen. The Pollenstorer ("pollen store") store it, as well as the nectar, in disused brood cells, around which further brood cells are finally placed. These vessels are lengthened parallel to the nest development. Lengths of five centimeters and more are possible. The pocket makers ("pocket makers") create pockets for the pollen around several brood cells.
On Mount Everest , flying bumblebees are observed up to an altitude of 5,600 meters, and under laboratory conditions some are still able to fly in air as thin as that of over 9,000 meters.
Collection techniques and communication
Bumblebees do not inform hive mates - like honey bees - with an elaborate dance, and yet they communicate with one another in the nest. In addition to chemical signals with which they mark collection points for nectar in the nest or flowers that have just been visited outside the nest, the animals pay close attention to each other. After their return, a successful forager moves so conspicuously and quickly in the nest that sometimes more than twice as many animals fly out to search for nectar. During the hectic movements of the returnee, fragrances from the flower that was originally visited are distributed, which, together with the nectar brought with them, are perceived by the other animals in the nest. These observers then fly out and look for these flowers. Bumblebees do not transmit any information about the direction or distance of a source of nectar, but they do transmit information that there is nectar in the vicinity. The different ways of communication between honey bees and bumblebees therefore have different evolutionary roots.
The long proboscis many types enables nectar collection from tiefkelchigen flowers. Bumblebees are strong enough to open even closed flowers. Short-nosed species often bite a lateral opening in flowers with long corolla tubes or flower spurs in order to gain direct access to the nectar ("blossom break-in", "nectar robbery"). The nectar is collected in the stomach and strangled up again in the nest. Bumblebees use their own enzymes to make honey from the nectar, but this is not of interest to humans because of its low supplies. The honey is stored in empty brood cells.
When collecting vibrations , the bumblebee hangs on a flower and generates vibrations through the decoupled flapping of its wings. As a result, plenty of pollen grains are released from the ripe anthers, even if they only have pore-shaped openings ("poricidal stamina" such as in tomato flowers), which then get caught in the hair of the bumblebee and cover almost the entire coat can. The bumblebee brushes the pollen out of the hair in flight and stores it in the “baskets” of the rear pair of legs.
The pollen is generally transported on the hind legs. To do this, the pollen is mixed by licking (spitting out nectar) into a malleable mass that is pressed between the long bristles of the hind legs. The "pollen pants" grow layer by layer. Depending on the time of day, the weather and the flowers flown over, pollen packages can become so large that they look like small wings. The color of the pollen packets ranges from light yellow to brown.
In the nest, the bumblebee looks for the brood cells that have been converted into pollen silos (in the case of "pollen storers") or the pollen pockets on brood cells (in the case of "pocket makers") in order to store the pollen packages. Above the opening, the bumblebee loosens the pollen packets in one piece from the leg. It often takes several attempts for the package to come off.
According to the latest studies, bumblebees can influence the start of flowering of plants in their favor. By deliberately biting through the leaves of plants that are not yet flowering, they stimulate them to flower prematurely. This effect can bring forward the start of flowering up to 30 days. In particular, hungry bumblebees with insufficient pollen supply tend to this behavior, which is stopped again as soon as the pollen supply increases.
A popular rumor has it that bumblebees cannot sting. Bumblebees have quite a large defensive sting ; but only female workers are able to sting with it. However, bumblebees do not sting immediately, but warn with a defense reaction beforehand. First, they raise their middle leg towards the attacker. When threatened, they throw themselves on their backs, stretch the sting apparatus in the direction of the attacker and hum loudly. If there is no retreat, attacks with bites and stings can also occur.
When a sting occurs, a poison is transmitted to the victim. However, bumblebees rarely sting and only in an emergency. If you step on a bumblebee, it can lead to a sting. The same is possible when holding a bumblebee. In contrast to the bee, the sting does not get stuck in the skin.
In humans, the sting only pinches slightly, but a sting from the injected venom, which is different from the venom of bees , can also be painful. The consequences are pain, redness, itching and swelling. Like the stings and poisons from bees and hornets, bumblebee stings are harmless to most people. There is only a risk of a severe allergic reaction for allergy sufferers . The stinger of a bumblebee has no barbs and therefore does not get stuck in the victim like that of a honey bee.
In contrast to other colonizing voices, honey bees , wasps and hornets , which occasionally defend their nest very aggressively in the event of a disturbance or danger, bumblebees rarely sting. The different bumblebee species have a different level of potential for aggression; among their relatives, however, the bumblebees are the most peaceful bearers of military spines. Occasionally it is said to have even happened that bumblebees pursue, sting and bite their prey. However, this is rare and the bumblebees only do it when destroying their nest.
As with wasps and honey bees, the drones do not have a stinger and therefore cannot sting.
In addition to the parasitic cuckoo bumblebees , the great woolly bee ( Anthidium manicatum ) is dangerous for the bumblebees. The males of the large woolly bee defend their territory against invading bees and bumblebees by flying towards them and bending their thorn-reinforced abdomen forwards shortly before the collision. Often the wings of the attacked are destroyed. The insects that were unable to fly as a result starve to death.
While wool bees damage individual bumblebees, the progeny of the wax moth can destroy an entire bumblebee colony. The wax moth, attracted by the scent of nectar and pollen, flies into the bumblebee's nest and lays eggs there. The larvae that hatch from it eat the honeycomb and the bumblebee eggs and larvae it contains. The offspring of the bumblebees do not appear and the affected bumblebee colony goes out.
Many species of bumblebee are known to be hosts to bee ants (family Mutillidae). The female bee ants are heavily armored, wingless and very defensive. They invade the bumblebee nests and lay an egg in each of the cells. After the entire brood has been consumed, the bee ant larvae pupate in the cell. Then later adult animals hatch. The infestation by a bee ant does not necessarily lead to the demise of the entire bumblebee colony.
Mites settle on the bumblebee and feed on their blood , which leads to weakening.
Bumblebees are dying
The kind of sugar mannose , indigestible for bees and bumblebees , has long been suspected of having caused the death of the bumblebees. However, according to recent findings, it does not occur in the nectar of these linden trees.
Laboratory tests have shown that the animals dying there have a very low sugar content in their bodies. Weakened bumblebees can be saved from death, for example, by offering them a few drops of sugar water with a small syringe on the ground, which they can ingest directly with their proboscis. From this the conclusion was drawn that, due to a lack of food in the vicinity of Linden, many other bumblebee colonies and bees also search for food here and there is therefore a severe shortage of supply. According to the theory, the bumblebees have then used so much energy for the approach that they can no longer seek out any other food source.
In contrast to honey bees, bumblebees have no time memory, which would also enable them to fly specifically to the trees that produce nectar in the morning and evening. Nor do they have any forms of communication such as dance languages , which would allow a much more targeted use of food sources by the entire bumblebee population. Therefore, despite the lack of nectar, this luring of bumblebees and bees by linden trees is only threatening for the bumblebee colonies. The bee colonies, which are much stronger in individuals , only lose relatively few of their so-called foragers . If these do not come back, the attractiveness of the destination automatically decreases due to the lack of dances.
An experiment from 2016/2017 showed that insecticides from the class of neonicotinoids cause populations of bumblebees to collapse dramatically. Certain pesticides are not directly lethal to bees - long considered but very comfortable. In a laboratory experiment, an active ingredient from the group of widespread neonicotinoids reduced the number of egg-laying bumblebees by 26 percent.
Honey bees can carry viruses such as B. the wing deformation virus transmitted to bumblebees.
The most powerful instrument of bumblebee protection is a sufficient supply of food with bumblebee-friendly wild plants, herbs , perennials, shrubs and trees throughout the bumblebee year from mid-February to the end of October. However, especially in early spring from mid-February to March and in summer from mid / late July to late October, the offer is often insufficient. In the settlement area, this effect is reinforced by the fact that insect friendliness has only played a subordinate role in garden culture in the last few decades and therefore many flowering plants that are largely worthless for bumblebees (and other insects and birds) have found widespread use in gardens and green spaces, e.g. B. Forsythia, magnolias, common lilac, cherry laurel and many cultivated forms with double flowers. Insect-conscious hobby gardeners, garden / landscape architects and municipal green space authorities now often plan their new plants or redesigns with the help of relevant flowering calendars, which indicate the nectar and pollen values of the various flowering plants in addition to the flowering time.
In agriculture, flower strips have been created at the edges of fields as agri-environmental measures and are intended to promote local biodiversity since the 1990s . In the settlement area, this is often done by the municipalities, nature conservation associations and private initiatives. A wide range of special seed mixtures for flowering areas has appeared on the market, also in small containers for private gardens. For all applications, a basic distinction is made between mixtures of annual, biennial or perennial plants. A full declaration with all the plant species it contains is not necessarily a matter of course, but it only helps a botanical layperson to a limited extent to assess the actual value of the respective mixture for bumblebees, wild bees and other insects. Critics complain that numerous mixtures are optimized for the human eye, but not for the demands of insects, and in some cases even contain species with double flowers that are completely worthless for the insects. The criticism is z. For example, the mixture “Mössinger Sommer”, which is only of low value for wild bees and bumblebees, is also largely composed of non-native seeds and therefore carries the risk of flora adulteration. The small wildflower seed sachets, which are often offered as give-aways , are also seen as poorly assessed and in most cases not conducive to bumblebees.
Bumblebee-conscious hobby gardeners and other initiators of flowering areas should therefore not rely solely on supplier information when selecting suitable seed mixtures, but rather seek reliable independent sources of information (examples:) for advice.
Another option for bumblebee protection is to install a bumblebee nest box , which, however, needs a little more care than a bird nest box. Above and below ground models are available in stores to meet the demands of the various species of bumblebee, but you can also build them yourself. It is advisable to attach a bumblebee hatch at the entrance of the nest box so that no parasites such as the wax moth can get into the nest. Even small mammals cannot overcome such an obstacle.
Cultural history and popular belief
Due to their size and their loud humming sound when flying, bumblebees are very prominent insects that also played a role in human cultural history. According to an old superstition, the bumblebees represented the embodiment of witches who could accept them if they left their bodies for it. In the local folk belief , it was also assumed that all witches present had to be burned if you lit a consecrated bumblebee wax candle in a church . According to another superstition, villains should appear in the form of a bumblebee as punishment after their death. Bumblebees buzzing underground were feared as spirits of the dead. According to a superstition, the devil also takes on the shape of a bumblebee, and at times it was customary to put a bumblebee in the mouth of participants in black masses instead of a host . In Swabia , the bumblebee was feared as a disease demon , and a bumblebee was buried to fight a cattle epidemic.
The popular belief of the money-making goblins, which should be locked in the purse in the shape of bumblebees and protect them from drying up, is completely different. A honey thief who manages to steal honey from the bumblebees unnoticed should also find a great treasure. In the weather forecast, bumblebees meant spring or sunny weather; if the bumblebees don't fly out, there will be rain.
Flight of the Bumblebee is probably the best-known piece of music by Nikolai Rimski-Korsakow , it is part of the opera Das Märchen vom Tsar Saltan . The onomatopoeic instrumentation , which is supposed toreproducethe flight noise of a bumblebee,is remarkable.
Artificial breeding and commercial importance
As early as 1912, the entomologist Frederick Sladen described how to get bumblebee queens to build nests in captivity. However, he lacked the prerequisites to fertilize the bumblebee queens under artificial conditions or to overwinter them. One of Sladen's discovery was that socializing two bumblebee queens increases the nest-building instinct. In these cases, the more dominant female begins to lay eggs more often, while the other takes on the role of a worker. Adding workers of the same or a different species of bumblebee has a similar effect. Later entomologists, who also raised bumblebees for scientific purposes, found that even adding workers to honeybees had a comparable effect. Ideal nesting conditions exist with a constant outside temperature of 28 degrees Celsius and high humidity. Mating occurs when males and females are brought together in light-colored cages. Newly mated queens could also be made to hibernate if they were given loose soil. They could then be stored in refrigerators for months. At the beginning of the 1970s, experience with artificial breeding and keeping in captivity had progressed so far that it was possible to go through a complete annual cycle for individual species. The dark bumblebee in particular seemed to be particularly easy to raise under artificial conditions. In the case of other species such as the rare earth-burrowing bumblebee , it has so far remained an exception to only induce them to build nests in captivity.
The commercial possibilities of artificially breeding bumblebees were initially overlooked. Initially it was mainly entomologists who dedicated themselves to labor-intensive bumblebee breeding. That changed in 1985 when the Belgian veterinarian and hobby entomologist Roland de Jonghe put a nest of dark bumblebees in a greenhouse where tomatoes were growing and found that bumblebees were very effective at pollinating the plants. Commercially important plants such as tomatoes and peppers are so-called vibratory pollinators . In order to achieve fruit set, labor-intensive manual pollination with electrical pollinators was necessary in greenhouses. This resulted in labor costs of around € 10,000 per hectare. Compared to this, the costs of artificial bumblebee farming were low. De Jonghe also found that plants pollinated by bumblebees were more productive. In 1987, De Jonghe founded Biobest , which is still one of the largest commercial breeders of bumblebees to this day. In 1988, the company raised just enough bumblebees to pollinate 40 hectares that were grown tomatoes. But as early as 1989 they began to export bumblebee nests to Holland, France and Great Britain. De Jonghe's success was imitated as early as 1988: The Dutch company "Koppert Biological Systems" started commercial breeding that year, followed in 1989 with the Dutch company "Bunting Bringman Bees", the third company to be active in this segment. In 1990 artificially reared bumblebees were also used in agriculture in Canada. The USA and Israel followed a year later, followed by Japan and Morocco a little later. By the turn of the millennium, it had become the global standard to rely on pollination by bumblebees when growing tomatoes. Exceptions are countries like Australia, where bumblebees do not occur naturally and where the legislation strictly prohibits the import of non-native species.
In the practice of pollination with bumblebees, complete bumblebees' nests are exposed in the greenhouses. The European companies that are active in artificial bumblebee breeding send more than a million bumblebee nests worldwide every year. One of the positive side effects of using bumblebees in agricultural vegetable cultivation is that they are accompanied by a significantly reduced use of insecticides and pesticides, as the use of these agents also endangers pollinators. One of the disadvantages is that most of the dark bumblebees that are artificially grown today can be traced back to wild bumblebees collected in Turkey. When using bumblebees in greenhouses, it is almost inevitable that bumblebees will escape from the greenhouses. There is a high probability that some of these escaped bumblebees will mate with wild bumblebees. This contributes to a falsification of the fauna. In the UK, vegetable growers are therefore encouraged to either destroy these imported nests when they are no longer in use, by burning them, or to kill the bumblebees by placing the nests in freezers. In the experience of the British entomologist Dave Goulsen, these recommendations are only implemented by a few vegetable farmers. Few growers have large enough freezers to do this. Burning the nests, which are made of cardboard, plastic and polystyrene , generates annoying exhaust gases. In Japan, it is now a legal requirement that greenhouses using bumblebees' nests have double doors and meshed hatches to prevent bumblebees from escaping. Meanwhile, however, there are feral dark bumblebees in Japan that go back to escaped bumblebees .
The experiences in South America are even more serious: Dark bumblebees that have escaped from Chilean greenhouses have been invasively spreading over the South American land mass since 1998 at a speed of around 200 km per year. On its way, for example, the native bumblebee species Bombus dalbomii dies out regionally a few years after the arrival of the dark bumblebee. With the industrially bred earth bumblebees, a unicellular parasite Crithidia bombi also came to the continent. It is believed that the combination of bumblebee and parasite is displacing the native bumblebee species with such great speed.
- Bumblebee Paradox : An apparent paradox in aerodynamics according to which bumblebees cannot fly
Dave Goulson : A sting in the tale. Random House, London 2013, ISBN 978-0-224-09689-8 .
- German: And yet it flies. A short history of the Hummel , translated by Bettina Hübner, Hanser Verlag, Munich 2014, ISBN 978-3-446-44039-5
- Joseph Gokcezade, Barbara-Amina Gereben-Krenn, Johann Neumayer: Field identification key for the bumblebees in Germany, Austria and Switzerland . Quelle & Meyer TB, 2nd edition 2018, ISBN 978-3-494-01787-7 .
- Eberhard von Hagen , Ambros Aichhorn: Bumblebees - determine, settle, multiply, protect . Fauna-Verlag, 6th edition, Nottuln 2014, 360 pages, ISBN 978-3-935980-32-6 .
- Bernd Heinrich : The bumblebee state - survival strategies of an ancient species . Ullstein-Taschenbuch-Verl., Munich 2001, ISBN 3-548-60041-7 .
- Helmut and Margrit Hintermeier: bees, bumblebees, wasps in the garden and in the landscape . Obst- und Gartenbauverlag, Munich 2002, ISBN 3-87596-099-8 .
- Volker Mauss: Identification key for bumblebees. 6th edition 1996, 52 p. German Youth Association for Nature Observation .
- Peter-Frank Röseler: The Bumblebee Garden. Triga, Gelnhausen 2001, ISBN 3-89774-169-5 .
- Günter R. Witte , Juliane Seger: Bumblebees need blooming land. Westarp Sciences, Magdeburg 1999, ISBN 3-89432-097-4 .
- Konrad Dettner, Werner Peters: Textbook of Entomology. Gustav Fischer, Berlin 2003, ISBN 3-8274-1102-5 .
- Johann Neumayer, Hannes F. Paulus : Ecology of alpine bumblebee communities: flower visit, resource allocation and energy balance. Investigations in the Eastern Alps of Austria. In: Stapfia. Volume 67, Linz 1999, , online (PDF) on ZOBODAT
- PH Williams: Phylogenetic relationships among bumblebees. in: Systematic entomology. Blackwell, Oxford 19.1994, 327-344,
- An annotated checklist of bumblebees with an analysis of patterns of description. in: Bulletin of the Natural History Museum (Entomology). Intercept, Andover 67.1998, 79-152,
- Current, also scientific information about bumblebees
- Website about bumblebees
- Very detailed, individual species are richly illustrated, list of threatened species
- US Bumblebee Populations Decline - AP Oct 9, 2007
- Easy identification of the most common bumblebee species (PDF; 60 kB)
- Field identification key for the bumblebees of Austria, Germany and Switzerland of the Biology Center Linz / Austria (PDF; 5.6 MB)
- Goulson: A Sting in the Tale , 2013, item 278
- Goulson: A Sting in the Tale , 2013, item 289
- Goulson: A Sting in the Tale , 2013, item 295
- RP MacFarlane, L. Gurr (1995): Distribution of bumble bees in New Zealand. New Zealand Entomologist 18, pp. 29-36.
- Goulson: A Sting in the Tale , item 549.
- Goulson: A Sting in the Tale , item 560.
- Goulson: A Sting in the Tale , item 566.
- Goulson: A Sting in the Tale , item 572.
- Goulson: A Sting in the Tale , position 589.
- Goulson: A Sting in the Tale , item 2221.
- Goulson: A Sting in the Tale , 2013, item 2199.
- Goulson: A Sting in the Tale , 2013, item 2277.
- Charles Darwin: On the Paths of the Bumblebee Men , Wikisource, accessed April 3, 2014
- Goulson: A Sting in the Tale , 2013, item 2245.
- Goulson: A Sting in the Tale , 2013, item 2251.
- Goulson: A Sting in the Tale , 2013, item 2263.
- Goulson: A Sting in the Tale , 2013, item 2268.
- Goulson: A Sting in the Tale , item 583.
- Goulson: A Sting in the Tale , 2013, item 583.
- Wild bees: flight distances at wildbienen.de, accessed on June 14, 2020.
- The Independent (June 1, 2008): Bumblebees set new insect record for high-altitude flying . (Last accessed: June 1, 2008.)
- A. Dornhaus, L. Chittka: Evolutionary origins of bee dances. Nature, Vol. 40, September 1999, p. 38. Summary ( Memento of May 3, 2009 in the Internet Archive )
- Bumblebees can influence the flowering time in their favor at nau.ch, accessed on July 18, 2020.
- Bumblebees bring plants to flower faster at innovations-report.de, accessed on July 18, 2020.
- Bumblebee sting: Bumblebees can sting ( memento from May 6, 2009 in the Internet Archive ) at aktion-hummelschutz.de, accessed on August 18, 2016.
- Sabine Hübner: And yet it flies . ISBN 978-3-446-44067-8 , pp. 320 .
- Further development of the people at pollenhoeschen.de, accessed on July 11, 2019.
- Toxic sugar in nectar? at nabu.de, accessed on August 18, 2016.
- Hummelsterben unter Linden at imkerverein-muelheim.de, accessed on August 18, 2016.
- 4. Competition from honey bees on flowering linden trees at pollenhoeschen.de, accessed on July 11, 2019.
- Neonicotinoids: Bumblebees lay fewer eggs In: Pharmazeutische Zeitung , August 15, 2017, accessed on August 24, 2017.
- Robyn Manley, Ben Temperton, Toby Doyle, Daisy Gates, Sophie Hedges, Michael Boots, Lena Wilfert, Hillary Young: Knock ‐ on community impacts of a novel vector: spillover of emerging DWV ‐ B from ‐infested honeybees to wild bumblebees. In: Ecology Letters. 2019, doi: 10.1111 / ele.13323 (German post ).
- Samantha A. Alger, P. Alexander Burnham, Humberto F. Boncristiani, Alison K. Brody, Olav Rueppell: RNA virus spillover from managed honeybees (Apis mellifera) to wild bumblebees (Bombus spp.). In: PLOS ONE. 14, 2019, p. E0217822, doi: 10.1371 / journal.pone.0217822 (German article ).
- Stefan Helget: The Bumblebee Garden . Retrieved May 26, 2021 .
- Bernhard Jaesch: Black list of "non-bee plants". Retrieved May 17, 2021 .
- Bee-friendly plants: The plant lexicon for balconies and gardens. Federal Ministry of Food and Agriculture (BMEL), April 2020, accessed on May 16, 2021 .
- pastures. Service Center Rural Areas (DLR) Rheinpfalz, accessed on May 16, 2021 .
- Flowering calendar. Apis e. V., Association for the Promotion of Apiculture of the North Rhine-Westphalia Chamber of Agriculture, accessed on May 16, 2021 .
- Manfred Radtke: Be careful with "Mössinger Sommer". BUND district group Rotenburg, accessed on May 13, 2021 .
- Creation of flower strips or flower areas. Julius Kühn Institute - Federal Research Institute for Cultivated Plants (JKI), accessed on May 17, 2021 .
- Paul Westrich: Improvement of the food supply: wildflower seed mixtures. Retrieved May 17, 2021 .
- Federal Agency for Nature Conservation: Application of native wood and seeds in the wild from March 1, 2020. Accessed on March 19, 2020 .
- man-made nesting boxes at nabu.de, accessed on June 11, 2020.
- Construction instructions: A bumblebee hatch for the bumblebee house. In: pollen panties. Accessed June 11, 2020 (German).
- Eberhard von Hagen: Hummeln: determine, settle, multiply, protect . 2nd Edition. Neumann - Neudamm, ISBN 3-7888-0546-3 , p. 256 .
- Goulson: A Sting in the Tale . 2013, item 2585.
- Goulson: A Sting in the Tale . 2013, item 2591.
- Goulson: A Sting in the Tale . 2013, item 2596.
- Goulson: A Sting in the Tale . 2013, item 2602.
- Article in the World on Commercial Breeding of Bumblebees and Other Beneficial Insects , accessed April 1, 2014
- Goulson: A Sting in the Tale . 2013, item 2607.
- Peter Prantner: Lucrative Hummel: The business with pollination. Chance observation with consequences. In: orf.at. April 23, 2018, accessed October 13, 2018 .
- Goulson: A Sting in the Tale . 2013, item 2613.
- Webpage of the company Biobest ( Memento from April 7, 2014 in the Internet Archive ), accessed on April 1, 2014
- Goulson: A Sting in the Tale . 2013, item 2619.
- Goulson: A Sting in the Tale . 2013, item 2636.
- Goulson: A Sting in the Tale . 2013, item 2642.
- Regula Schmid-Hempel, et al .: The invasion of southern South America by imported bumblebees and associated parasites . In: Journal of Animal Ecology . 83, No. 4, 2014, pp. 823-837. doi : 10.1111 / 1365-2656.12185 . .