Bees can suffer serious effects from toxic chemicals in their environments. These include various synthetic chemicals, particularly insecticides, as well as a variety of naturally occurring chemicals from plants, such as ethanol resulting from the fermentation of organic materials. Bee intoxication can result from exposure to ethanol from fermented nectar, ripe fruits, and manmade and natural chemicals in the environment.
The effects of alcohol on bees are sufficiently similar to the effects of alcohol on humans that honey bees have been used as models of human ethanol intoxication. The metabolism of bees and humans is sufficiently different that bees can safely collect nectars from plants that contain compounds toxic to humans. The honey produced by bees from these toxic nectars can be poisonous if consumed by humans. In addition, natural processes can introduce toxic substances into honey produced from nontoxic nectar.
The introduction of certain chemical substances—such as ethanol or pesticides or defensive toxic biochemicals produced by plants—to a bee's environment can cause the bee to display abnormal or unusual behavior and disorientation. In sufficient quantities, such chemicals can poison and even kill the bee. The effects of alcohol on bees have long been recognized. For example, John Cumming described the effect in an 1864 publication on beekeeping. [1]
When bees become intoxicated from ethanol consumption or poisoned with other chemicals, their balance is affected. Charles Abramson's group at Oklahoma State University has put inebriated bees on running wheels, where they exhibit locomotion difficulties. They also put honey bees in shuttle-boxes that used a stimulus to encourage the bees to move, and found that they were less mobile as they became more intoxicated. [2]
An intoxicated bee often extends its proboscis. Inebriated bees spend more time flying. If a bee is sufficiently intoxicated, it becomes unable to walk. Inebriated bees typically have many more flying accidents. Some bees that consume ethanol become too inebriated to find their way back to the hive, and die as a result. [2] Bozic et al. (2006) found that alcohol consumption by honeybees disrupts foraging and social behaviors, and has some similar effects to poisoning with insecticides. [3] Some bees become more aggressive after consuming alcohol. [4]
Exposure to alcohol can have a prolonged effect on bees, lasting as long as 48 hours. [5] This phenomenon is also observed in fruit flies [6] and is connected to the neurotransmitter octopamine in fruit flies, which is also present in bees. [7]
In 1999, David Sandeman suggested that bee inebriation models may be valuable for understanding vertebrate ethanol intoxication, given the homology and convergence of insect and vertebrate nervous systems. [8]
The bees are fed ethanol solutions and their behavior observed. [2] Researchers place the bees in harnesses, and feed them varying concentrations of alcohol in into sugar solutions. [2] [9] Tests of locomotion, foraging, social interaction and aggressiveness are performed; functioning is impaired much as in humans. [9] The interaction of bees with antabuse (disulfiram, a treatment for alcoholism) has been tested as well. [10]
Bees can be severely and even fatally affected by pesticides, [11] [12] [13] [14] fertilizers, [15] [16] [17] copper sulfate (more lethal than spinosad), [18] [16] and other chemicals that man has introduced into the environment. [19]
This problem has been the object of growing concern. For example, researchers at the University of Hohenheim are studying how bees can be poisoned by exposure to seed disinfectants. [20] In France, the Ministry of Agriculture commissioned an expert group, the Scientific and Technical Committee for the Multifactorial Study on Bees (CST), to study the intoxicating and sometimes fatal effects of chemicals used in agriculture on bees. [21] Researchers at the Bee Research Institute and the Department of Food Chemistry and Analysis in the Czech Republic have pondered the intoxicating effects of various chemicals used to treat winter rapeseed crops. [22] Romania suffered a severe case of widespread bee intoxication and extensive bee mortality from deltamethrin in 2002. [23] The United States Environmental Protection Agency has published standards for testing chemicals for bee intoxication. [24]
Bees can be substantially affected by natural compounds in the environment besides ethanol. For example, Dariusz Szlachetko of the Department of Plant Taxonomy and Nature Conservation, Gdańsk University observed wasps in Poland acting in a very sleepy (possibly inebriated) manner after eating nectar derived from the North American orchid Neottia . [25]
Detzel and Wink (1993) published an extensive review of 63 types of plant allelochemicals and their effects on bees. 39 chemical compounds repelled bees (primarily alkaloids, coumarins, and saponins), while three terpene compounds attracted bees. They report that 17 out of 29 allelochemicals are toxic at some levels (especially alkaloids, saponins, cardiac glycosides and cyanogenic glycosides). [26]
Various plants have pollen toxic to honey bees, in some cases killing the adults, as in Toxicoscordion ; in other cases weakening the brood, as in Heliconia . Other plants with toxic pollen include Spathodea campanulata and Ochroma lagopus . Both the pollen and nectar of the California Buckeye ( Aesculus californica ) are toxic to honeybees. [27]
Some plants rely on using intoxicating chemicals to produce inebriated bees, and use this inebriation as part of their reproductive strategy. One plant that may do this is the South American bucket orchid (Coryanthes sp.), an epiphyte. The bucket orchid attracts male euglossine bees with its scent, derived from a variety of aromatic compounds. The bees store these compounds in specialized spongy pouches inside their swollen hind legs, as they appear to use the scent (or derivatives thereof) in order to attract females. The flower is constructed in such a way as to make the surface almost impossible to cling to, with smooth, downward-pointing hairs; the bees commonly slip and fall into the fluid in the bucket, and the only navigable route out is a narrow, constricting passage that either glues a "pollinium" (a pollen sack) on their body (if the flower has not yet been visited) or removes any pollinium that is there (if the flower has already been visited). The passageway constricts after a bee has entered, and holds it there for a few minutes, allowing the glue to dry and securing the pollinium. It has been suggested that this process may involve inebriation of the bees. [28] [29] [30] [31]
Van der Pijl and Dodson (1966) observed that bees of the genera Eulaema and Xylocopa exhibit symptoms of inebriation after consuming nectar from the orchids Sobralia violacea and Sobralia rosea . [32] [33]
A number of plants produce alkaloids which can taint honey made from their flowers in different ways. The plant genus Coriaria produces poisonous honey, due to the toxin tutin. [34] Morphine-containing honey has been reported in areas where opium poppy cultivation is widespread. [35] Tecoma stans is a nontoxic plant, but honey from its flowers is poisonous. [36] [37] Plants including Rhododendron and heathers (Ericaceae) produce the neurotoxin grayanotoxin. This is toxic to humans but not to bees. Honey from these flowers can be psychoactive, or even toxic to humans. [38] Honey can ferment and produce ethanol. Animals, such as birds, that have eaten honey fermented in the sun can be found intoxicated. [39]
Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamily Apoidea. They are currently considered a clade, called Anthophila. There are over 20,000 known species of bees in seven recognized biological families. Some species – including honey bees, bumblebees, and stingless bees – live socially in colonies while most species (>90%) – including mason bees, carpenter bees, leafcutter bees, and sweat bees – are solitary.
A honey bee is a eusocial flying insect within the genus Apis of the bee clade, all native to mainland Afro-Eurasia. After bees spread naturally throughout Africa and Eurasia, humans became responsible for the current cosmopolitan distribution of honey bees, introducing multiple subspecies into South America, North America, and Australia.
A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains.
Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds. Pollinating agents can be animals such as insects, for example beetles or butterflies; birds, and bats; water; wind; and even plants themselves. Pollinating animals travel from plant to plant carrying pollen on their bodies in a vital interaction that allows the transfer of genetic material critical to the reproductive system of most flowering plants. When self-pollination occurs within a closed flower. Pollination often occurs within a species. When pollination occurs between species, it can produce hybrid offspring in nature and in plant breeding work.
Imidacloprid is a systemic insecticide belonging to a class of chemicals called the neonicotinoids which act on the central nervous system of insects. The chemical works by interfering with the transmission of stimuli in the insect nervous system. Specifically, it causes a blockage of the nicotinergic neuronal pathway. By blocking nicotinic acetylcholine receptors, imidacloprid prevents acetylcholine from transmitting impulses between nerves, resulting in the insect's paralysis and eventual death. It is effective on contact and via stomach action. Because imidacloprid binds much more strongly to insect neuron receptors than to mammal neuron receptors, this insecticide is more toxic to insects than to mammals.
A worker bee is any female bee that lacks the reproductive capacity of the colony's queen bee and carries out the majority of tasks needed for the functioning of the hive. While worker bees are present in all eusocial bee species, the term is rarely used for bees other than honey bees, particularly the European honey bee. Worker bees of this variety are responsible for approximately 80% of the world's crop pollination services.
Pesticides vary in their effects on bees. Contact pesticides are usually sprayed on plants and can kill bees when they crawl over sprayed surfaces of plants or other areas around it. Systemic pesticides, on the other hand, are usually incorporated into the soil or onto seeds and move up into the stem, leaves, nectar, and pollen of plants.
Zoophily, or zoogamy, is a form of pollination whereby pollen is transferred by animals, usually by invertebrates but in some cases vertebrates, particularly birds and bats, but also by other animals. Zoophilous species frequently have evolved mechanisms to make themselves more appealing to the particular type of pollinator, e.g. brightly colored or scented flowers, nectar, and appealing shapes and patterns. These plant-animal relationships are often mutually beneficial because of the food source provided in exchange for pollination.
In zoology, a nectarivore is an animal which derives its energy and nutrient requirements from a diet consisting mainly or exclusively of the sugar-rich nectar produced by flowering plants.
A tremble dance is a dance performed by forager honey bees of the species Apis mellifera to recruit more receiver honey bees to collect nectar from the workers.
Pouyannian mimicry is a form of mimicry in plants that deceives an insect into attempting to copulate with a flower. The flower mimics a potential female mate of a male insect, which then serves the plant as a pollinator. The mechanism is named after the French lawyer and amateur botanist Maurice-Alexandre Pouyanne. The resemblance that he noted is visual, but the key stimuli that deceive the pollinator are often chemical and tactile.
Clothianidin is an insecticide developed by Takeda Chemical Industries and Bayer AG. Similar to thiamethoxam and imidacloprid, it is a neonicotinoid. Neonicotinoids are a class of insecticides that are chemically similar to nicotine, which has been used as a pesticide since the late 1700s. Clothianidin and other neonicotinoids act on the central nervous system of insects as an agonist of nAChR, the same receptor as acetylcholine, the neurotransmitter that stimulates and activating post-synaptic acetylcholine receptors but not inhibiting AChE. Clothianidin and other neonicotinoids were developed to last longer than nicotine, which is more toxic and which breaks down too quickly in the environment.
The western honey bee or European honey bee is the most common of the 7–12 species of honey bees worldwide. The genus name Apis is Latin for 'bee', and mellifera is the Latin for 'honey-bearing' or 'honey-carrying', referring to the species' production of honey.
Colony collapse disorder (CCD) is an abnormal phenomenon that occurs when the majority of worker bees in a honey bee colony disappear, leaving behind a queen, plenty of food, and a few nurse bees to care for the remaining immature bees. While such disappearances have occurred sporadically throughout the history of apiculture, and have been known by various names, the syndrome was renamed colony collapse disorder in early 2007 in conjunction with a drastic rise in reports of disappearances of western honey bee colonies in North America. Beekeepers in most European countries had observed a similar phenomenon since 1998, especially in Southern and Western Europe; the Northern Ireland Assembly received reports of a decline greater than 50%. The phenomenon became more global when it affected some Asian and African countries as well. From 1990 to 2021, the United Nation’s FAO calculated that the worldwide number of honeybee colonies increased 47%, reaching 102 million.
Acetamiprid is an organic compound with the chemical formula C10H11ClN4. It is an odorless neonicotinoid insecticide produced under the trade names Assail, and Chipco by Aventis CropSciences. It is systemic and intended to control sucking insects (Thysanoptera, Hemiptera, mainly aphids) on crops such as leafy vegetables, citrus fruits, pome fruits, grapes, cotton, cole crops, and ornamental plants. It is also a key pesticide in commercial cherry farming due to its effectiveness against the larvae of the cherry fruit fly.
Flower constancy or pollinator constancy is the tendency of individual pollinators to exclusively visit certain flower species or morphs within a species, bypassing other available flower species that could potentially contain more nectar. This type of foraging behavior puts selective pressures on floral traits in a process called pollinator-mediated selection. Flower constancy is different from other types of insect specialization such as innate preferences for certain colors or flower types, or the tendency of pollinators to visit the most rewarding and abundant flowers.
Dendrobium christyanum is a species of orchid (Orchidaceae) endemic to the Chinese island of Hainan.
The California carpenter bee or Western carpenter bee, Xylocopa californica, is a species of carpenter bee in the order Hymenoptera, and it is native to western North America.
Thiamethoxam is the ISO common name for a mixture of cis-trans isomers used as a systemic insecticide of the neonicotinoid class. It has a broad spectrum of activity against many types of insects and can be used as a seed dressing.
Peponapis pruinosa is a species of solitary bee in the tribe Eucerini, the long-horned bees. Its common name is the eastern cucurbit bee. It may be called the squash bee, but this name can also apply to other species in its genus, as well as the other squash bee genus, Xenoglossa. This bee occurs in North America from the East Coast of the United States to the West Coast and into Mexico. It is an oligolege, specializing on a few host plants, the squashes and gourds of genus Cucurbita. Its range expanded as human agriculture spread throughout North America and squash plants became more abundant and widespread. It may also have spread naturally as the range of its favored wild host plant Cucurbita foetidissima expanded.
bee intoxication.
The first hymenopteran to visit has difficulties coping with the rostrellum but the later ones to arrive easily escape, soaked, drunk, and often having completed their pollinating function.