75% of crops worldwide depend on pollination by animals, particularly bees. In fact, the production of pollinator-dependent crops in the U.S. is valued at over $50 billion per year! Bees are arguably the most important pollinators for both crops and wild plants. The vast majority of food production in the United States relies on the European honey bee, a non-native species, for pollination. Honey bees provide $15 billion annually in pollination services to North American crops. However, dependence on this single species increases the risk of predator, parasite, and pathogen development. Managed honey bee colonies declined 59% in the period from 1949 to 2007 and they may not be able to support our agricultural needs in the future. Because native bees are not affected by the same pests and diseases that affect honey bees, they are crucial for crop production. Native bees have the potential to replace or augment the pollination of crops by honey bees in the United States, however, half of native bee species are declining and one-quarter are at risk of extinction. In order to preserve our precious food supply and biodiversity, we need to protect native bees.
Native bees provide more than $3 billion dollars in pollination services to the United States every year. In a study of crop pollination by honey bees and native bees in New Jersey and Pennsylvania, Winfree et al. (2007) found that wild bee species, on average, deposit more pollen per visit than honey bees. Native bees alone were sufficient enough to pollinate watermelon crops fully at 91% of farms studied, compared to 78% for honey bees. In another study by Garibaldi et al. (2013), wild pollinators increased the fruit set, the proportion of a plant’s flowers that develop into mature fruits or seeds, by twice that of honeybees. Wild insects provided better-quality pollination than honey bees in this study. Reilly et al. (2020) report that wild bees deposited 1.5 to 2 times more pollen per visit than honey bees for apple and tart cherry crops even though honey bee visitation rates were higher. Additionally, the value of wild pollinators to apple crops were estimated to be $1.06 billion. Kremen et al. (2002) found that local native bee communities alone could provide sufficient pollination services for watermelon crops at organic farms. They discovered that honey bees were not abundant enough on organic farms, so farmers relied on native bees to pollinate their crops. Wild bees may also be able to pollinate more effectively than honey bees in areas affected by climate change. Diverse wild bee communities have been shown to increase pollination rates and crop yields. These studies suggest that native bees need to be conserved because they contribute greatly to food production.
Although native bees are incredibly important to agriculture and in decline, the media disproportionately reports the decline of honey bees when they should be bringing attention to the plight of native bees. In a study of Australian pollinator media coverage over ten years, the European honey bee constituted 50% of coverage while native bees were only 15%. Pesticides are viewed as a significant threat to bees because the media highly publicizes lobbying by environmental organizations and governments to restrict the application of agrochemicals such as neonicotinoid pesticides. Other threats including pathogen spillover and climate change are often not covered by the media.
The majority of the public is not knowledgeable of native bees in general, but they do believe bees are important for the environment. In a survey of Canadian residents, half of the participants incorrectly believed that the European honey bee was a native bee, though two-thirds believed that bees should be protected because they provide valuable ecosystem services. One-quarter of the respondents did not know how they could personally help bee conservation. This demonstrates the necessity for education and outreach programs that educate the public on the plight of native bees and individual actions they can take to help.
There are several easily doable actions you can take to help native bees. Planting native plants in gardens will provide bees with a source of nectar and pollen and will benefit specialist native bees who only feed on specific native plants. Native plants should be a variety of shapes, colors, and sizes to maintain diversity and attract different native bee species. Ensure that there is a plant blooming throughout the year because different bee species are active at different times of the year. Provide more habitat for bees in your yard by reducing lawns and mowing less frequently as well as leaving said green debris on the ground so that ground-nesting bees can make homes. Refrain from using insecticides, especially neonicotinoids which become absorbed in all parts of the plant and can kill bees or cause them to have trouble foraging and finding the hive. Provide bees with water by filling a shallow plate with pebbles and water, as the pebbles serve as landing spots for the bees to safely drink without falling in. 70% of solitary bees dig a nest in the ground to lay their eggs and 30% use tunnels in dead trees or logs. Nesting spaces for solitary bee species can be provided by leaving bare soil unmulched in the garden and keeping dead trees or fallen logs. Purchase or make a native bee nesting house with replaceable nesting tubes to offer habitat and places for solitary bees to lay their eggs.
Without native bees, we would not have a significant amount of the food we eat and natural ecosystems would be disrupted; we need to take action to protect this precious pollinator before it is too late.
Sources
Colla, S. R., & MacIvor, J. S. (2017). Questioning public perception, conservation policy, and recovery actions for honeybees in North America. Conservation Biology, 31(5), 1202-1204.
Garibaldi, L. A., Steffan-Dewenter, I., Winfree, R., Aizen, M. A., Bommarco, R., Cunningham, S. A., ... & Klein, A. M. (2013). Wild pollinators enhance fruit set of crops regardless of honey bee abundance. science, 339(6127), 1608-1611.
Geldmann, J., & González-Varo, J. P. (2018). Conserving honey bees does not help wildlife. Science, 359(6374), 392-393.
Holland, J. (2015, May 24). 9 Ways You Can Help Bees and Other Pollinators At Home. Retrieved March 07, 2021, from https://www.nationalgeographic.com/animals/article/150524-bees-pollinators-animals-science-gardens-plants
Kopec, K. & Burd, L.A. (2017). Pollinators in Peril: A Systematic Review of North American and Hawaiian native bees [White paper]. Center for Biological Diversity. https://www.biologicaldiversity.org/campaigns/native_pollinators/pdfs/Pollinators_in_Peril.pdf
Kremen, C., Williams, N. M., & Thorp, R. W. (2002). Crop pollination from native bees at risk from agricultural intensification. Proceedings of the National Academy of Sciences, 99(26), 16812-16816.
Mallinger, R. E., Gaines-Day, H. R., & Gratton, C. (2017). Do managed bees have negative effects on wild bees?: A systematic review of the literature. PloS one, 12(12), e0189268.
Mizejewski, D. (2018, April 09). Six ways to help bees And Beesponsible. Retrieved March 07, 2021, from https://blog.nwf.org/2018/04/six-ways-to-help-bees-and-beesponsible/
Reilly, J. R., Artz, D. R., Biddinger, D., Bobiwash, K., Boyle, N. K., Brittain, C., ... & Winfree, R. (2020). Crop production in the USA is frequently limited by a lack of pollinators. Proceedings of the Royal Society B, 287(1931), 20200922.
van Vierssen Trip, N., MacPhail, V. J., Colla, S. R., & Olivastri, B. (2020). Examining the public's awareness of bee (Hymenoptera: Apoidae: Anthophila) conservation in Canada. Conservation Science and Practice, 2(12), e293.
Winfree, R., Williams, N. M., Dushoff, J., & Kremen, C. (2007). Native bees provide insurance against ongoing honey bee losses. Ecology letters, 10(11), 1105-1113.
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Written by Clara Pitsker
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