These “key messages” are a set of selected facts about pollination. You may want to pick and choose from these statements as appropriate for your audience and topic, or use them as a guide for your presentation.

General
Many people think only of allergies when they hear the word pollen, but pollen plays a vital role in the health of our environment. Pollen, the plant’s male sex cells, must be transferred from the anther to the stigma of the same or another flower for the plant to produce fruit and seed. While some plants are self- or wind-pollinated, the great majority of flowering plants cannot move pollen without help from an animal pollinator. 1
Pollinators make up a significant portion of the total diversity of species on this planet. In fact, between 200,000 - 300,000 invertebrate species-such as butterflies, beetles, moths, flies, mosquitoes, and bees—are estimated to serve globally as pollinators2 3 as well as around 2,000 vertebrates species, including birds, mammals, and reptiles.
A majority of plants, more than 70 percent of species, depend on insects, birds, bats, and other animals to transport the pollen for them.
Worldwide, at least thirty percent of 1500 crop plant species depend on pollination by bees and other insects.4 5

Economic Benefits
Pollinators play a significant role in the production of over 150 food crops in the U.S.—among them apples, almonds, blueberries, cranberries, kiwis, melons, pears, plums, and squash. 6 7
Pollinators are important in the production of an estimated 30 percent of the human diet, fibers, edible oils, medicines created from plants, and others important products around the world.
In the U.S., the annual benefit of managed honey bees to agriculture was estimated as $14.6 billion in 2000.8
Native, unmanaged pollinators—primarily bees— are estimated to contribute $3 billion to the value of crops pollination in the U.S.. 9
The southeastern blueberry bee illustrates the economic significance of native pollinators. In her few weeks as an adult, a single female bee visits about 50,000 blueberry flowers, resulting in over 6,000 marketable blueberries worth about $75. 10
Studies in California’s Central Valley have shown that a suite of three dozen or more native bee species provide pollination services on a single farm and can deliver sufficient pollination even for crops with a “heavy” pollination requirement such as watermelon. In watermelon up to 1,000 grains of pollen must be deposited on each flower within only a few hours to get marketable fruit.11 12
Bumble bees have long been recognized as important pollinators of crops and native plants. In recent years, they have been reared commercially and used to pollinate greenhouse crops, particularly tomatoes and eggplant13










Pollinator Declines
The National Research Council report, Status of Pollinators in North America, unequivocally states that pollinator declines are occurring. The report identifies the main causes of decline as habitat loss, pesticide use, and, especially in honey bees, diseases. It spotlights the urgency of action to conserve pollinators and their habitat.14
Many species of wild pollinators are in decline. Disruptions of localized pollination systems, and declines of certain species of pollinators, have been reported on every continent except Antarctica.15 16
The number of managed honey bee colonies in the U.S. has decreased by more than 50 percent since 1945. Another 50% have been lost since then, half of that during the during the 1990s. 17 18
Many factors are believed to be responsible for what is being called “Colony Collapse Disorder”: some combination of pathogens, parasites; environmental stresses, and management stresses are likely to be the cause.19 Many experts suggest that these declines illustrate the danger of our heavy reliance on a single species for most of our pollination needs.
Habitat loss and fragmentation are two of the greatest threats to native pollinators. Foraging areas and nesting sites of many pollinating organisms are jeopardized when wild lands are converted to domestic uses such as housing, suburban development, agriculture, or pasture.20 21 22
Pesticides also pose a major threat to insect pollinators. Changes in the type and timing of pesticide use, avoidance of overspray, better regulation, and organic agricultural methods can reduce pollinator mortality rates. 23 24 25
The impact of diseases, parasites, and pathogens on pollinator populations is of growing concern. Managed honey bees are affected by parasitic mites, diseases such as foulbrood, and pathogens. Commercially reared bumble bees are also affected by diseases and pathogens, and there is evidence that these can spread from commercial colonies to wild colonies around greenhouses. 26 27 
Further research is necessary to improve the understanding of pollination dynamics and the consequences of pollinator decline. Specifically, we need to know more about the effects on wild pollinators of pesticides, grazing, logging, and urban sprawl; the significance of diminishing pollinator populations and the potential for cascading extinction; and the identification of economically important plant-pollinator relationships. 28

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Sources

1 Nabhan, G.P., and S.L. Buchmann. 1997. Services provided by pollinators. In: Daily G. (Ed). Nature’s Services. Washington D.C.: Island Press. pp. 133–150.
2 Kearns, C.A., D.W. Inouye, and N. Waser. 1998. Endangered mutualisms: the conservation of plant-pollinator interactions. Annual Review of Ecology and Systematics 29: 83–112.
3 DeGrandi-Hoffman, G. 2003. Honey bees in U.S. agriculture: past, present, and future. In: Strickler K. and J.H. Cane (Eds). For Nonnative Crops, Whence Pollinators of the Future, Lanham, MD: Entomological Society of America, pp. 11-20.
4 Buchmann, S.L. 1996. Competition between honey bees and native bees in the Sonoran desert and global bee conservation issues. In: Matheson, A., C. O’Toole, S. Buchmann, P. Westrick, and I. Williams (Eds). The Conservation of Bees. New York: Academic Press. pp. 125–142.
5 Klein, A.M., B.E. Vaissiere, J.H. Cane, I. Steffan-Dewenter, S.A. Cunningham, C. Kremen, and T. Tscharntke. 2007. Importance of pollinators in changing landscapes for world crops. Proceedings of the Royal Society of London, Series B 274: 303-313.
6 Cane, J.H. 1997. Lifetime monetary value of individual pollinators: the bee Habropoda laboriosa at rabbiteye blueberry (Vaccinium ashei Reade). Acta Horticulturae 446: 67–70.
7 Kevan, P. G. 1975. Pollination and environmental conservation. Environmental Conservation 2(4): 293–297.
8 Morse, R.A., and N.W. Calderone. 2000. The value of honey bees as pollinators of U.S. crops in 2000. Bee Culture 128: 1–15.
9 Losey, J.E., and M. Vaughan. 2006. The economic value of ecological services provided by insects. BioScience 56(4): 311-323.
10 Cane, J.H. 1997. Lifetime monetary value of individual pollinators: the bee Habropoda laboriosa at rabbiteye blueberry (Vaccinium ashei Reade). Acta Horticulturae 446: 67–70.
11 Kremen, C., R.L. Bugg, N. Nicola, S.A. Smith, R.W. Thorp, and N.M. Williams. 2002. Native bees, native plants, and crop pollination in California. Fremontia 30(3-4): 41-49.
12 Kremen, C., N.M. Williams, and R.W. Thorp. 2002. Crop pollination from native bees at risk from agricultural intensification. Proceedings of the National Academy of Sciences 99(26): 16812-16816.
13 Thorp, R.W. 2003. Bumble bees (Hymenoptera: Apidae): commercial use and environmental concerns. K. Strickler K. and J.H. Cane (Eds). For Nonnative Crops, Whence Pollinators of the Future, Lanham, MD: Entomological Society of America. pp. 21-40.
14 National Research Council. 2006. Status of Pollinators in North America. Washington, DC: National Academies Press.
15 National Research Council. 2006. Status of Pollinators in North America. Washington, DC: National Academies Press.
16 Kearns, C.A., D.W. Inouye, and N. Waser. 1998. Endangered mutualisms: the conservation of plant-pollinator interactions. Annual Review of Ecology and Systematics 29: 83–112.
17 Allen-Wardell, G. et al. 1998. The potential consequences of pollinator declines on the conservation of biodiversity and stability of food crop yields. Conservation Biology 12: 8–17.
18 Michener, C.D. 2000. The Bees of the World. Baltimore, MD: Johns Hopkins University Press. 914 pp.
19 U.S. Department of Agriculture, Agricultural Research Service. 2008. Colony Collapse Disorder: A Complex Buzz. Agricultural Research, May/June 2008. Online at http://www.ars.usda.gov/is/AR/archive/may08/colony0508.htm, accessed on August 20, 2008.
20 National Research Council. 2006. Status of Pollinators in North America. Washington, DC: National Academies Press.
21 Kearns, C.A., D.W. Inouye, and N. Waser. 1998. Endangered mutualisms: the conservation of plant-pollinator interactions. Annual Review of Ecology and Systematics 29: 83–112.
22 Groom, M.J. 1998. Allee effects limit population viability of an annual plant. American Naturalist 151(6): 487–496.
23 Kevan, P. G. 1975. Pollination and environmental conservation. Environmental Conservation 2(4): 293–297.
24 National Research Council. 2006. Status of Pollinators in North America. Washington, DC: National Academies Press.
25 DeGrandi-Hoffman, G. 2003. Honey bees in U.S. agriculture: past, present, and future. In: Strickler K. and J.H. Cane (Eds). For Nonnative Crops, Whence Pollinators of the Future, Lanham, MD: Entomological Society of America, pp. 11-20.
26 DeGrandi-Hoffman, G. 2003. Honey bees in U.S. agriculture: past, present, and future. In: Strickler K. and J.H. Cane (Eds). For Nonnative Crops, Whence Pollinators of the Future, Lanham, MD: Entomological Society of America, pp. 11-20.
27 Colla, S.R., M.C. Otterstatter, R.J. Gegear, and J.D. Thomson. 2006. Plight of the bumble bee: pathogen spillover from commercial to wild populations. Biological Conservation 129(4): 461-467.
28 Kearns, C.A., D.W. Inouye, and N. Waser. 1998. Endangered mutualisms: the conservation of plant-pollinator interactions. Annual Review of Ecology and Systematics 29: 83–112.

Revised June 20, 2008.

Reference as: Ecological Society of America. Communicating Ecosystem Services Pollination Toolkit: Key Points. Updated June 20, 2008. Online at www.esa.org/ecoservices


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