Pollinator decline
Encyclopedia
The term pollinator decline refers to the reduction in abundance of pollinator
s in many ecosystem
s worldwide during the end of the twentieth century.
Pollinators participate in sexual reproduction of many plant
s, by ensuring cross-pollination
, essential for some species
, or a major factor in ensuring genetic diversity
for others. Since plant
s are the primary food
source for animal
s, the reduction of one of the primary pollination agents, or even their possible disappearance, has raised concern, and the conservation
of pollinators has become part of biodiversity
conservation efforts.
have grown larger, the need for concentrated pollinators at bloom
time has grown. At the same time populations of many pollinators have been declining, and this decline has become a major environmental issue today. Pollination management
seeks to protect, enhance, and augment agricultural pollination.
For example, feral honey bee
populations in the US have dropped about 90% in the past 50 years, except for the Southwest where they have been replaced by Africanized bee
s. At the same time managed honey bee colonies
have dropped by about two thirds.
In North America, during the winter and spring of 2006 – 2007, was a considerable decline in commercially managed honeybee colonies, with losses of about one third of honeybees population. This event is named colony collapse disorder
, and has appeared in 35 states of USA affecting honeybees, reporting losses in honeybees colonies as high as 80 to 100 percent for some beekeepers.
Monoculture
needs very high populations of bees at bloom, but can make the area quite barren, or even toxic when the bloom is done.
The study of pollinator decline is also interesting to some scientists, as bees have the potential to become a keystone indicator species
of environmental degradation. Any changes in their abundance and diversity will influence the abundance and diversity of the prevailing plant species. This is a mutual dependency as bees rely on a steady nectar source
and pollen source
throughout the year to build up their hive.
and food
for wildlife
is immense and difficult to quantify.
It is commonly said that about one third of human nutrition is due to bee pollination. This includes the majority of fruit
s, many vegetable
s (or their seed crop) and secondary effects from legumes such as alfalfa
and clover
fed to livestock.
In 2000, Drs. Roger Morse
and Nicholas Calderone of Cornell University
, attempted to quantify the effects of just one pollinator, the Western honey bee, on only US
food crops. Their calculations came up with a figure of US $14.6 billion in food crop value.
There has not been sufficient study to quantify the effects of pollinator decline on wild plants and wild life that depend on them for feed. Some plants on the endangered species list are endangered because they have lost their normal, native pollinators because of displacement by invasive honey bees. Honey bee
s are not native to the Western Hemisphere
, so the loss of honey bees may not represent a threat to native plants; the role of honey bees in the Western Hemisphere is almost exclusively agricultural. To the extent that honey bees compete with native bee species, a decrease in the honey bee population may be beneficial to native plants and pollinators.
There are international iniatives (e.g. the International Pollinator Iniative (IPI)) that highlight the need for public participation and awareness of pollinator, such as bees, conservation
s on crops during bloom, or to allow the pesticide to drift to blooming weeds that bees are visiting. Yet such applications are frequently done, with little enforcement of the bee protection directions. Pesticide misuse
has driven beekeepers out of business, but can affect native wild bees even more, because they have no human to move or protect them.
Bumblebee
populations are in jeopardy in cotton
-growing areas, since they are dosed repeatedly when pesticide applicators apply insecticides on blooming cotton fields while the bees are foraging.
Widespread aerial applications for mosquito
es, med-flies
, grasshopper
s, gypsy moth
s and other insects leave no islands of safety where wild insect pollinators can reproduce and repopulate. One such program can reduce or endanger pollinator populations
for several years.
Many homeowners feel that dandelions and clover
are weeds, that lawns should only be grass, and that they should be highly treated with pesticides. This makes a hostile environment for bees, butterflies
and other pollinators.
See also:
mite
s, acarina
mites, and the small African hive beetle to new areas of the world, causing much loss of bees in the areas where they do not have much resistance to these pests. Imported fire ants have decimated ground nesting bees in wide areas of the southern US.
and homes for wild bees. Large tractor mounted rotary mowers may make farms and roadsides look neater, but they remove bee habitat at the same time. Old crops such as sweet clover and buckwheat
, which were very good for bees have been disappearing. Urban and suburban development pave or build over former areas of pollinator habitat.
Clearcut logging
, especially when mixed forest
s are replaced by uniform age pine
planting, causes serious loss of pollinators, by removing hardwood
bloom that feeds bees early in the season, and by removing hollow trees used by feral honey bees, and dead stubs used by many solitary bees.
s to gain their energy requirements for the migration. In some areas development or agriculture has disrupted and broken up these traditional corridors, and the pollinators have to find alternative routes or discontinue migration. A good example is the endangered lesser long-nosed bat (Leptonycteris curasoae) which was formerly the main pollinator of a number of cactus species in southwestern United States. Its numbers have severely declined, in part due to disruption of the nectar corridors that it formerly followed. Other migratory pollinators include monarch butterflies
and some hummingbird
s.
s" on the Internet primarily yields information on removal rather than information regarding bees in a positive light. Recent hysteria regarding killer bees
has contributed to these views. Beekeepers find increased vandalism
of their hives, more difficulty in finding locations for bee yards, and more people inclined to sue
the local beekeeper if they are stung, even if it is by a yellow jacket
.
species, and is suspected of interference with migratory birds
may also impact pollination. Moths are important pollinator
s of night blooming flower
s and moth disorientation may reduce or eliminate the plant
s ability to reproduce, thus leading to long term ecological
effects. This is a new field and this environmental issue needs further study.
reduced invasive honey bee populations in the US, native pollinators sometimes have made recoveries, restored to their natural niche by the loss.
have discovered that air pollution
from automobile
s and power plants has been inhibiting the ability of pollinator
s such as bee
s and butterflies
to find the fragrances of flower
s. Pollutant
s such as ozone
, hydroxyl
, and nitrate
radical
s bond quickly with volatile scent molecules of flowers, which consequently travel shorter distances intact. There results a vicious cycle in which pollinators travel increasingly longer distances to find flowers providing them nectar, and flowers receive inadequate pollination
to reproduce and diversify. http://www.eurekalert.org/pub_releases/2008-04/uov-ffd041008.php
crops, but increasingly is for contract
pollination to supply the needs for growers of crops that require it.
groups. Prairie restoration, establishment of wildlife preserves, and encouragement of diverse wildlife landscaping rather than monoculture lawns, are examples of ways to help pollinators.
and alkali bee
s in alfalfa pollination and bumblebee
s in greenhouses for tomatoes are used to augment and in some cases replace honey bees. A wide variety of other bees can be found in the environment that are specialist pollinators (some only using one plant species). However, most of these alternative insects' value as pollinators and their relationships with plants are as yet little known.
In the US, some think that other pollinators will in time replace the lost honey bees, blamed on introduced
acarine and varroa mites, but general pollinator decline was already happening before these entered the picture. Only in a few areas are wild populations of pollinators building up; in most areas they are declining as quickly as honey bees.
Furthermore pollinators cannot be exchanged on a one-for-one basis. They are not all equal. Some are generalists, some are specialists. Some are brawny; some are feeble. Some have long tongues; some short. Some work at colder temperatures than others. Bees may deliberately collect pollen, but have different collection techniques, which can greatly affect their efficiency as pollinators.
Flowers are frequently specifically adapted to one pollinator
, or a small group of pollinators because of floral structure, color, odor, nectar guides, etc. Proposed alternative pollinators may not be physically capable of accomplishing pollination, or they may not be attracted to the flower of that plant species, or they may rob nectar by cutting sepals, thus avoiding pollination. Understanding the pollination needs of a species is vital to understanding of a plant species, yet this is often poorly understood. In horticulture it is critical to the economic success of the grower, and crops have sometimes been abandoned from general use in an area because of lack of understanding of pollinator needs.
Pollinator
A pollinator is the biotic agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain...
s in many ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s worldwide during the end of the twentieth century.
Pollinators participate in sexual reproduction of many plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s, by ensuring cross-pollination
Pollination
Pollination is the process by which pollen is transferred in plants, thereby enabling fertilisation and sexual reproduction. Pollen grains transport the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself...
, essential for some species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
, or a major factor in ensuring genetic diversity
Genetic diversity
Genetic diversity, the level of biodiversity, refers to the total number of genetic characteristics in the genetic makeup of a species. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary....
for others. Since plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s are the primary food
Food
Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals...
source for animal
Animal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...
s, the reduction of one of the primary pollination agents, or even their possible disappearance, has raised concern, and the conservation
Conservation ethic
Conservation is an ethic of resource use, allocation, and protection. Its primary focus is upon maintaining the health of the natural world: its, fisheries, habitats, and biological diversity. Secondary focus is on materials conservation and energy conservation, which are seen as important to...
of pollinators has become part of biodiversity
Biodiversity
Biodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions...
conservation efforts.
Observation
As plantingsAgriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
have grown larger, the need for concentrated pollinators at bloom
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
time has grown. At the same time populations of many pollinators have been declining, and this decline has become a major environmental issue today. Pollination management
Pollination management
Pollination Management is the label for horticultural practices that accomplish or enhance pollination of a crop, to improve yield or quality, by understanding of the particular crop's pollination needs, and by knowledgeable management of pollenizers, pollinators, and pollination...
seeks to protect, enhance, and augment agricultural pollination.
For example, feral honey bee
Honey bee
Honey bees are a subset of bees in the genus Apis, primarily distinguished by the production and storage of honey and the construction of perennial, colonial nests out of wax. Honey bees are the only extant members of the tribe Apini, all in the genus Apis...
populations in the US have dropped about 90% in the past 50 years, except for the Southwest where they have been replaced by Africanized bee
Africanized bee
Africanized honey bees, known colloquially as "killer bees", are a hybrid variety of the European honeybee , generated by a man-made breeding of the African honey bee, A. m. scutellata, with various European honey bees such as the Italian bee A. m. ligustica and A. m. iberiensis. These bees are far...
s. At the same time managed honey bee colonies
Beekeeping
Beekeeping is the maintenance of honey bee colonies, commonly in hives, by humans. A beekeeper keeps bees in order to collect honey and other products of the hive , to pollinate crops, or to produce bees for sale to other beekeepers...
have dropped by about two thirds.
In North America, during the winter and spring of 2006 – 2007, was a considerable decline in commercially managed honeybee colonies, with losses of about one third of honeybees population. This event is named colony collapse disorder
Colony Collapse Disorder
Colony collapse disorder is a phenomenon in which worker bees from a beehive or European honey bee colony abruptly disappear. While such disappearances have occurred throughout the history of apiculture, the term colony collapse disorder was first applied to a drastic rise in the number of...
, and has appeared in 35 states of USA affecting honeybees, reporting losses in honeybees colonies as high as 80 to 100 percent for some beekeepers.
Monoculture
Monoculture
Monoculture is the agricultural practice of producing or growing one single crop over a wide area. It is also known as a way of farming practice of growing large stands of a single species. It is widely used in modern industrial agriculture and its implementation has allowed for large harvests from...
needs very high populations of bees at bloom, but can make the area quite barren, or even toxic when the bloom is done.
The study of pollinator decline is also interesting to some scientists, as bees have the potential to become a keystone indicator species
Indicator species
An indicator species is any biological species that defines a trait or characteristic of the environment. For example, a species may delineate an ecoregion or indicate an environmental condition such as a disease outbreak, pollution, species competition or climate change...
of environmental degradation. Any changes in their abundance and diversity will influence the abundance and diversity of the prevailing plant species. This is a mutual dependency as bees rely on a steady nectar source
Nectar source
A nectar source is a flowering plant that produces nectar as part of its reproductive strategy. These plants create nectar, which attract pollinating insects and sometimes other animals such as birds....
and pollen source
Pollen source
The term pollen source is often used in the context of beekeeping and refers to flowering plants as a source of pollen for bees or other insects. Bees collect pollen as a protein source to raise their brood. For the plant, the pollinizer, this can be an important mechanism for sexual reproduction,...
throughout the year to build up their hive.
Consequences
The value of bee pollination in human nutritionNutrition
Nutrition is the provision, to cells and organisms, of the materials necessary to support life. Many common health problems can be prevented or alleviated with a healthy diet....
and food
Food
Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals...
for wildlife
Wildlife
Wildlife includes all non-domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative....
is immense and difficult to quantify.
It is commonly said that about one third of human nutrition is due to bee pollination. This includes the majority of fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
s, many vegetable
Vegetable
The noun vegetable usually means an edible plant or part of a plant other than a sweet fruit or seed. This typically means the leaf, stem, or root of a plant....
s (or their seed crop) and secondary effects from legumes such as alfalfa
Alfalfa
Alfalfa is a flowering plant in the pea family Fabaceae cultivated as an important forage crop in the US, Canada, Argentina, France, Australia, the Middle East, South Africa, and many other countries. It is known as lucerne in the UK, France, Australia, South Africa and New Zealand, and known as...
and clover
Clover
Clover , or trefoil, is a genus of about 300 species of plants in the leguminous pea family Fabaceae. The genus has a cosmopolitan distribution; the highest diversity is found in the temperate Northern Hemisphere, but many species also occur in South America and Africa, including at high altitudes...
fed to livestock.
In 2000, Drs. Roger Morse
Roger Morse
Roger A. Morse, Ph.D. was a bee biologist who taught many beekeepers both the rudiments and the finer practices, through his research and publications. During his long career, three new parasites of the honeybee, acarine mite, varroa mite and African small hive beetle were introduced to the USA...
and Nicholas Calderone of Cornell University
Cornell University
Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...
, attempted to quantify the effects of just one pollinator, the Western honey bee, on only US
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
food crops. Their calculations came up with a figure of US $14.6 billion in food crop value.
There has not been sufficient study to quantify the effects of pollinator decline on wild plants and wild life that depend on them for feed. Some plants on the endangered species list are endangered because they have lost their normal, native pollinators because of displacement by invasive honey bees. Honey bee
Honey bee
Honey bees are a subset of bees in the genus Apis, primarily distinguished by the production and storage of honey and the construction of perennial, colonial nests out of wax. Honey bees are the only extant members of the tribe Apini, all in the genus Apis...
s are not native to the Western Hemisphere
Western Hemisphere
The Western Hemisphere or western hemisphere is mainly used as a geographical term for the half of the Earth that lies west of the Prime Meridian and east of the Antimeridian , the other half being called the Eastern Hemisphere.In this sense, the western hemisphere consists of the western portions...
, so the loss of honey bees may not represent a threat to native plants; the role of honey bees in the Western Hemisphere is almost exclusively agricultural. To the extent that honey bees compete with native bee species, a decrease in the honey bee population may be beneficial to native plants and pollinators.
Increasing public awareness
The steady increase in beekeeper migration (for pollination service on agricultural crops) has masked the issue of pollinator decline from much public awareness, however sudden blocks to such migration could have catastrophic results on the global food supply.There are international iniatives (e.g. the International Pollinator Iniative (IPI)) that highlight the need for public participation and awareness of pollinator, such as bees, conservation
Pesticide misuse
It is a label violation to apply most insecticideInsecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
s on crops during bloom, or to allow the pesticide to drift to blooming weeds that bees are visiting. Yet such applications are frequently done, with little enforcement of the bee protection directions. Pesticide misuse
Pesticide misuse
Under United States laws, pesticide misuse is the use of a pesticide in a way that violates laws regulating their use or endangers humans or the environment; many of these regulations are laid out in the Federal Insecticide, Fungicide, and Rodenticide Act...
has driven beekeepers out of business, but can affect native wild bees even more, because they have no human to move or protect them.
Bumblebee
Bumblebee
A bumble bee is any member of the bee genus Bombus, in the family Apidae. There are over 250 known species, existing primarily in the Northern Hemisphere although they are common in New Zealand and in the Australian state of Tasmania.Bumble bees are social insects that are characterised by black...
populations are in jeopardy in cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
-growing areas, since they are dosed repeatedly when pesticide applicators apply insecticides on blooming cotton fields while the bees are foraging.
Widespread aerial applications for mosquito
Mosquito
Mosquitoes are members of a family of nematocerid flies: the Culicidae . The word Mosquito is from the Spanish and Portuguese for little fly...
es, med-flies
Drosophila
Drosophila is a genus of small flies, belonging to the family Drosophilidae, whose members are often called "fruit flies" or more appropriately pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit...
, grasshopper
Grasshopper
The grasshopper is an insect of the suborder Caelifera in the order Orthoptera. To distinguish it from bush crickets or katydids, it is sometimes referred to as the short-horned grasshopper...
s, gypsy moth
Gypsy moth
The gypsy moth, Lymantria dispar, is a moth in the family Lymantriidae of Eurasian origin. Originally ranging from Europe to Asia, it was introduced to North America in the late 1860s and has been expanding its range ever since...
s and other insects leave no islands of safety where wild insect pollinators can reproduce and repopulate. One such program can reduce or endanger pollinator populations
Endangered arthropod
An endangered arthropod is defined here as any of a number of species within the phylum Arthropoda, whose extinction is likely in the foreseeable future . Estimating the number of arthropod endangered species is extremely difficult, primarily because a vast number of the species themselves are...
for several years.
Many homeowners feel that dandelions and clover
Clover
Clover , or trefoil, is a genus of about 300 species of plants in the leguminous pea family Fabaceae. The genus has a cosmopolitan distribution; the highest diversity is found in the temperate Northern Hemisphere, but many species also occur in South America and Africa, including at high altitudes...
are weeds, that lawns should only be grass, and that they should be highly treated with pesticides. This makes a hostile environment for bees, butterflies
Butterfly
A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...
and other pollinators.
See also:
- Endangered arthropodEndangered arthropodAn endangered arthropod is defined here as any of a number of species within the phylum Arthropoda, whose extinction is likely in the foreseeable future . Estimating the number of arthropod endangered species is extremely difficult, primarily because a vast number of the species themselves are...
- Imidacloprid effects on bee populationImidacloprid effects on bee populationImidacloprid is a systemic neonicotinoid insecticide produced by the German chemical firm Bayer CropScience and sold under such trade names as Gaucho, Admire, Merit, Advantage, Confidor, Provado, and Winner. It acts as a neurotoxin and interferes with the transmission of nerve impulses in insects...
- RegentRegent (insecticide)Regent is a trademark for a broad spectrum systemic insecticide containing the active ingredient fipronil. Fipronil is an insecticide discovered and developed by Rhône-Poulenc between 1985-87. It was placed on the market in 1993. Regent's rights have been purchased by BASF. It acts by contact and...
Rapid transfer of parasites and diseases of pollinator species around the world
Increased international commerce within modern times has moved diseases such as American foulbrood and chalkbrood, and parasites such as varroaVarroa
Varroa is a genus of parasitic mites associated with honey bees, placed in its own family, Varroidae. The genus was named for Marcus Terentius Varro, a Roman scholar who was also a beekeeper.-History and behavior:...
mite
Mite
Mites, along with ticks, are small arthropods belonging to the subclass Acari and the class Arachnida. The scientific discipline devoted to the study of ticks and mites is called acarology.-Diversity and systematics:...
s, acarina
Acarina
Acari are a taxon of arachnids that contains mites and ticks. The diversity of the Acari is extraordinary and its fossil history goes back to at least the early Devonian period. As a result, acarologists have proposed a complex set of taxonomic ranks to classify mites...
mites, and the small African hive beetle to new areas of the world, causing much loss of bees in the areas where they do not have much resistance to these pests. Imported fire ants have decimated ground nesting bees in wide areas of the southern US.
Loss of habitat and forage
The push to remove hedgerows and other "unproductive" land in some farm areas removes habitatHabitat (ecology)
A habitat is an ecological or environmental area that is inhabited by a particular species of animal, plant or other type of organism...
and homes for wild bees. Large tractor mounted rotary mowers may make farms and roadsides look neater, but they remove bee habitat at the same time. Old crops such as sweet clover and buckwheat
Buckwheat
Buckwheat refers to a variety of plants in the dicot family Polygonaceae: the Eurasian genus Fagopyrum, the North American genus Eriogonum, and the Northern Hemisphere genus Fallopia. Either of the latter two may be referred to as "wild buckwheat"...
, which were very good for bees have been disappearing. Urban and suburban development pave or build over former areas of pollinator habitat.
Clearcut logging
Logging
Logging is the cutting, skidding, on-site processing, and loading of trees or logs onto trucks.In forestry, the term logging is sometimes used in a narrow sense concerning the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard...
, especially when mixed forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s are replaced by uniform age pine
Pine
Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...
planting, causes serious loss of pollinators, by removing hardwood
Hardwood
Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...
bloom that feeds bees early in the season, and by removing hollow trees used by feral honey bees, and dead stubs used by many solitary bees.
Nectar corridors
Migratory pollinators require a continuous supply of nectar sourceNectar source
A nectar source is a flowering plant that produces nectar as part of its reproductive strategy. These plants create nectar, which attract pollinating insects and sometimes other animals such as birds....
s to gain their energy requirements for the migration. In some areas development or agriculture has disrupted and broken up these traditional corridors, and the pollinators have to find alternative routes or discontinue migration. A good example is the endangered lesser long-nosed bat (Leptonycteris curasoae) which was formerly the main pollinator of a number of cactus species in southwestern United States. Its numbers have severely declined, in part due to disruption of the nectar corridors that it formerly followed. Other migratory pollinators include monarch butterflies
Monarch butterfly
The Monarch butterfly is a milkweed butterfly , in the family Nymphalidae. It is perhaps the best known of all North American butterflies. Since the 19th century, it has been found in New Zealand, and in Australia since 1871 where it is called the Wanderer...
and some hummingbird
Hummingbird
Hummingbirds are birds that comprise the family Trochilidae. They are among the smallest of birds, most species measuring in the 7.5–13 cm range. Indeed, the smallest extant bird species is a hummingbird, the 5-cm Bee Hummingbird. They can hover in mid-air by rapidly flapping their wings...
s.
Hive destruction
Bees are often viewed negatively by homeowners and other property owners. A search for "carpenter beeCarpenter bee
Carpenter bees are large, hairy bees distributed worldwide. There are some 500 species of carpenter bee in 31 subgenera...
s" on the Internet primarily yields information on removal rather than information regarding bees in a positive light. Recent hysteria regarding killer bees
Africanized bee
Africanized honey bees, known colloquially as "killer bees", are a hybrid variety of the European honeybee , generated by a man-made breeding of the African honey bee, A. m. scutellata, with various European honey bees such as the Italian bee A. m. ligustica and A. m. iberiensis. These bees are far...
has contributed to these views. Beekeepers find increased vandalism
Vandalism
Vandalism is the behaviour attributed originally to the Vandals, by the Romans, in respect of culture: ruthless destruction or spoiling of anything beautiful or venerable...
of their hives, more difficulty in finding locations for bee yards, and more people inclined to sue
Lawsuit
A lawsuit or "suit in law" is a civil action brought in a court of law in which a plaintiff, a party who claims to have incurred loss as a result of a defendant's actions, demands a legal or equitable remedy. The defendant is required to respond to the plaintiff's complaint...
the local beekeeper if they are stung, even if it is by a yellow jacket
Wasp
The term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor an ant. Almost every pest insect species has at least one wasp species that preys upon it or parasitizes it, making wasps critically important in natural control of their...
.
Light pollution
Increasing use of outside artificial lights, which interfere with the navigational ability of many mothMoth
A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...
species, and is suspected of interference with migratory birds
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
may also impact pollination. Moths are important pollinator
Pollinator
A pollinator is the biotic agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain...
s of night blooming flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s and moth disorientation may reduce or eliminate the plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s ability to reproduce, thus leading to long term ecological
Ecology
Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...
effects. This is a new field and this environmental issue needs further study.
Threat by invasive honey bees
Many native pollinators decline in population when faced with competition from invasive honey bees. For example, the western honey bee is invasive in the United States, the wild population consisting entirely of feral bees escaped from European bee colonies imported to fertilize non-native, old-world crops. Where colony collapse disorderColony Collapse Disorder
Colony collapse disorder is a phenomenon in which worker bees from a beehive or European honey bee colony abruptly disappear. While such disappearances have occurred throughout the history of apiculture, the term colony collapse disorder was first applied to a drastic rise in the number of...
reduced invasive honey bee populations in the US, native pollinators sometimes have made recoveries, restored to their natural niche by the loss.
Air pollution
Researchers at the University of VirginiaUniversity of Virginia
The University of Virginia is a public research university located in Charlottesville, Virginia, United States, founded by Thomas Jefferson...
have discovered that air pollution
Air pollution
Air pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or cause damage to the natural environment or built environment, into the atmosphere....
from automobile
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...
s and power plants has been inhibiting the ability of pollinator
Pollinator
A pollinator is the biotic agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain...
s such as bee
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
s and butterflies
Butterfly
A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...
to find the fragrances of flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s. Pollutant
Pollutant
A pollutant is a waste material that pollutes air, water or soil, and is the cause of pollution.Three factors determine the severity of a pollutant: its chemical nature, its concentration and its persistence. Some pollutants are biodegradable and therefore will not persist in the environment in the...
s such as ozone
Ozone
Ozone , or trioxygen, is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope...
, hydroxyl
Hydroxyl
A hydroxyl is a chemical group containing an oxygen atom covalently bonded with a hydrogen atom. In inorganic chemistry, the hydroxyl group is known as the hydroxide ion, and scientists and reference works generally use these different terms though they refer to the same chemical structure in...
, and nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...
radical
Radical (chemistry)
Radicals are atoms, molecules, or ions with unpaired electrons on an open shell configuration. Free radicals may have positive, negative, or zero charge...
s bond quickly with volatile scent molecules of flowers, which consequently travel shorter distances intact. There results a vicious cycle in which pollinators travel increasingly longer distances to find flowers providing them nectar, and flowers receive inadequate pollination
Pollination
Pollination is the process by which pollen is transferred in plants, thereby enabling fertilisation and sexual reproduction. Pollen grains transport the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself...
to reproduce and diversify. http://www.eurekalert.org/pub_releases/2008-04/uov-ffd041008.php
Solutions
The decline of pollinators is compensated to some extent by beekeepers becoming migratory, following the bloom northward in the spring from southern wintering locations. Migration may be for traditional honeyHoney
Honey is a sweet food made by bees using nectar from flowers. The variety produced by honey bees is the one most commonly referred to and is the type of honey collected by beekeepers and consumed by humans...
crops, but increasingly is for contract
Contract
A contract is an agreement entered into by two parties or more with the intention of creating a legal obligation, which may have elements in writing. Contracts can be made orally. The remedy for breach of contract can be "damages" or compensation of money. In equity, the remedy can be specific...
pollination to supply the needs for growers of crops that require it.
Conservation and restoration efforts
Efforts are being made to sustain pollinator diversity in agro- and natural eco-systems by some environmentalEnvironmental movement
The environmental movement, a term that includes the conservation and green politics, is a diverse scientific, social, and political movement for addressing environmental issues....
groups. Prairie restoration, establishment of wildlife preserves, and encouragement of diverse wildlife landscaping rather than monoculture lawns, are examples of ways to help pollinators.
Use of alternative pollinators
Honey bees are usually the most widely chosen insects in most managed pollination situations. However they are not the most efficient pollinators of some flowers. Alternative pollinators, such as for example, leafcutterAlfalfa leafcutter bee
Megachile rotundata, the alfalfa leafcutter bee or lucerne leafcutter bee is a European bee that has been introduced to other regions...
and alkali bee
Alkali bee
The alkali bee, Nomia melanderi, is a ground-nesting bee native to deserts and semi-arid desert basins of the western United States.It is an effective pollinator for alfalfa....
s in alfalfa pollination and bumblebee
Bumblebee
A bumble bee is any member of the bee genus Bombus, in the family Apidae. There are over 250 known species, existing primarily in the Northern Hemisphere although they are common in New Zealand and in the Australian state of Tasmania.Bumble bees are social insects that are characterised by black...
s in greenhouses for tomatoes are used to augment and in some cases replace honey bees. A wide variety of other bees can be found in the environment that are specialist pollinators (some only using one plant species). However, most of these alternative insects' value as pollinators and their relationships with plants are as yet little known.
In the US, some think that other pollinators will in time replace the lost honey bees, blamed on introduced
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
acarine and varroa mites, but general pollinator decline was already happening before these entered the picture. Only in a few areas are wild populations of pollinators building up; in most areas they are declining as quickly as honey bees.
Furthermore pollinators cannot be exchanged on a one-for-one basis. They are not all equal. Some are generalists, some are specialists. Some are brawny; some are feeble. Some have long tongues; some short. Some work at colder temperatures than others. Bees may deliberately collect pollen, but have different collection techniques, which can greatly affect their efficiency as pollinators.
Flowers are frequently specifically adapted to one pollinator
Pollination syndrome
Pollination syndromes are suites of flower traits that have evolved in response to natural selection imposed by different pollen vectors, which can be abiotic or biotic, such as birds, bees, flies, and so forth. These traits include flower shape, size, colour, odour, reward type and amount, nectar...
, or a small group of pollinators because of floral structure, color, odor, nectar guides, etc. Proposed alternative pollinators may not be physically capable of accomplishing pollination, or they may not be attracted to the flower of that plant species, or they may rob nectar by cutting sepals, thus avoiding pollination. Understanding the pollination needs of a species is vital to understanding of a plant species, yet this is often poorly understood. In horticulture it is critical to the economic success of the grower, and crops have sometimes been abandoned from general use in an area because of lack of understanding of pollinator needs.
See also
- Bees and toxic chemicalsBees and toxic chemicalsBees can suffer serious effects from toxic chemicals in their environments. These include various synthetic chemicals, such as insecticides and fertilizers, as well as a variety of naturally occurring chemicals from plants, such as ethanol resulting from the fermentation of organic material...
- Colony collapse disorderColony Collapse DisorderColony collapse disorder is a phenomenon in which worker bees from a beehive or European honey bee colony abruptly disappear. While such disappearances have occurred throughout the history of apiculture, the term colony collapse disorder was first applied to a drastic rise in the number of...
- Diseases of the honey bee
- Endangered arthropodEndangered arthropodAn endangered arthropod is defined here as any of a number of species within the phylum Arthropoda, whose extinction is likely in the foreseeable future . Estimating the number of arthropod endangered species is extremely difficult, primarily because a vast number of the species themselves are...
- Pesticide toxicity to beesPesticide toxicity to beesPesticides 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 media...
- Imidacloprid effects on bee populationImidacloprid effects on bee populationImidacloprid is a systemic neonicotinoid insecticide produced by the German chemical firm Bayer CropScience and sold under such trade names as Gaucho, Admire, Merit, Advantage, Confidor, Provado, and Winner. It acts as a neurotoxin and interferes with the transmission of nerve impulses in insects...
- Regent (insecticide)Regent (insecticide)Regent is a trademark for a broad spectrum systemic insecticide containing the active ingredient fipronil. Fipronil is an insecticide discovered and developed by Rhône-Poulenc between 1985-87. It was placed on the market in 1993. Regent's rights have been purchased by BASF. It acts by contact and...