Fewer Pollinators = Fewer Crops

Bee population decline threatens major crop yields in U.S and global food security

Crop yields for major crops such as apples, blueberries, and cherries across the U.S. are being limited by a lack of pollinators due to the decline of the wild bee population, according to new research, which was the most comprehensive study of its kind. Researchers noted that as most of the world’s crops depend on honeybees and wild bees for pollination; declines in both populations also raise a concern about global food security.

“We found that many crops are pollination-limited, meaning crop production would be higher if crop flowers received more pollination,” said senior author Rachael Winfree, a professor in the Department of Ecology, Evolution, and Natural Resources in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick.

The research is said to be the most comprehensive study of its kind to date.

“We also found that honey bees and wild bees provided similar amounts of pollination overall,” she added.

“Managing habitat for native bee species and/or stocking more honey bees would boost pollination levels and could increase crop production.”

Pollination by wild and managed insects is crucial for most crops, including those essential for food security. In the U.S., the production of crops that depend on pollinators produces more than 50 billion dollars a year.

Recent evidence shows that European honeybees and some native wild bee species are declining. Scientists gathered data on insect pollination of crop flowers and yields at 131 farms across the U.S. and British Columbia in Canada.


Image credit: Flickr

The yields included apples, highbush blueberries, sweet cherries, tart cherries, almond, watermelon, and pumpkin. Crops that showed evidence of being limited by pollination were apples, sweet cherries, tart cherries, and blueberries, indicating that yields are lower than what they would be with full pollination. Wild bees and honey bees provided the same amount of pollinations for most crops.

The yearly production value of wild pollinators for all seven crops was approximately 1.5 billion dollars in the U.S. The value of wild bee pollination for all crops dependent on pollinator would be much greater, the researchers said.

“Our findings show that pollinator declines could translate directly into decreased yields for most of the crops studied.”

The results indicate that adopting practices that conserve wild bees– like enhancing wildflowers and using managed pollinators other than honey bees– may possibly boost yields. Meanwhile, increasing investment in honey bee colonies would be another alternative.


Crop production in the USA is frequently limited by a lack of pollinators – Reilly, J. R. et al. – Proceedings of the Royal Society B: Biological Sciences – DOI: 10.1098/rspb.2020.0922


Most of the world’s crops depend on pollinators, so declines in both managed and wild bees raise concerns about food security. However, the degree to which insect pollination is actually limiting current crop production is poorly understood, as is the role of wild species (as opposed to managed honeybees) in pollinating crops, particularly in intensive production areas. We established a nationwide study to assess the extent of pollinator limitation in seven crops at 131 locations situated across major crop-producing areas of the USA. We found that five out of seven crops showed evidence of pollinator limitation. Wild bees and honeybees provided comparable amounts of pollination for most crops, even in agriculturally intensive regions. We estimated the nationwide annual production value of wild pollinators to the seven crops we studied at over $1.5 billion; the value of wild bee pollination of all pollinator-dependent crops would be much greater. Our findings show that pollinator declines could translate directly into decreased yields or production for most of the crops studied, and that wild species contribute substantially to the pollination of most study crops in major crop-producing regions.

Featured image credit: Flickr

from:    https://watchers.news/2020/07/30/bee-population-decline-threatens-major-crop-yields-in-u-s-and-global-food-security/

Consider the Bees….


Important new study on bees:


Image for Mobile Phone-Induced Honeybee Worker PipingA careful new study from Switzerland by Daniel Favre, published online April 13, 2011, demonstrates the effects of cell phones on honeybees.

More than 80 sound recordings were taken from 5 different hives during February through June 2009. A cell phone was place in the hives near the bees. When the cell phone was off, or on standby mode, the bees were not disturbed. When the cell phone was turned on, the effect was dramatic: within 25 to 40 minutes the sounds made by the bees increased in intensity and frequency, producing the “worker piping signal.” If the cell phone was turned off immediately, the bees calmed down within 2 or 3 minutes. If the cell phone was left on for 20 hours and then turned off, the piping signal continued for up to 12 hours more. The effect was consistent and repeatable.

Worker piping is usually produced by bees preparing to leave the hive in a swarm.

The author refers to another study recently done in India. In that study, when a mobile phone was kept continuously on near a beehive it resulted in collapse of the colony in 5 to 10 days, with the worker bees failing to return home.



Ved Parkash Sharma and Neelima R. Kumar.



Ulrich Warnke2007 A Brochure Series authored by Ulrich Warnke, internationally renowned bioscientist at Saarland University

http://www.hese-project.org/hese-uk/en/papers/warnke_bbm.pdf 1.5MB



from:    https://www.cellphonetaskforce.org/bees/

Hive Collapse and Pesticides

‘Highly Likely’ Insecticides Trigger Bee Colony Collapse: Harvard Study

Activist Post

Two widely used neonicotinoids—a class of insecticide—appear to significantly harm honey bee colonies over the winter, particularly during colder winters, according to a new study from Harvard School of Public Health (HSPH). The study replicated a 2012 finding from the same research group that found a link between low doses of imidacloprid and Colony Collapse Disorder (CCD), in which bees abandon their hives over the winter and eventually die. The new study also found that low doses of a second neonicotinoid, clothianidin, had the same negative effect.

Further, although other studies have suggested that CCD-related mortality in honey bee colonies may come from bees’ reduced resistance to mites or parasites as a result of exposure to pesticides, the new study found that bees in the hives exhibiting CCD had almost identical levels of pathogen infestation as a group of control hives, most of which survived the winter. This finding suggests that the neonicotinoids are causing some other kind of biological mechanism in bees that in turn leads to CCD.

The study appears online May 9, 2014 in the Bulletin of Insectology (link at bottom).

“We demonstrated again in this study that neonicotinoids are highly likely to be responsible for triggering CCD in honey bee hives that were healthy prior to the arrival of winter,” said lead author Chensheng (Alex) Lu, associate professor of environmental exposure biology at HSPH.

Since 2006, there have been significant losses of honey bees from CCD. Pinpointing the cause is crucial to mitigating this problem since bees are prime pollinators of roughly one-third of all crops worldwide. Experts have considered a number of possible causes, including pathogen infestation, beekeeping practices, and pesticide exposure. Recent findings, including a 2012 study by Lu and colleagues, suggest that CCD is related specifically to neonicotinoids, which may impair bees’ neurological functions. Imidacloprid and clothianidin both belong to this group.Lu and his co-authors from the Worcester County Beekeepers Association studied the health of 18 bee colonies in three locations in central Massachusetts from October 2012 through April 2013. At each location, the researchers separated six colonies into three groups—one treated with imidacloprid, one with clothianidin, and one untreated.

There was a steady decline in the size of all the bee colonies through the beginning of winter—typical among hives during the colder months in New England. Beginning in January 2013, bee populations in the control colonies began to increase as expected, but populations in the neonicotinoid-treated hives continued to decline. By April 2013, 6 out of 12 of the neonicotinoid-treated colonies were lost, with abandoned hives that are typical of CCD. Only one of the control colonies was lost—thousands of dead bees were found inside the hive—with what appeared to be symptoms of a common intestinal parasite called Nosema ceranae.

While the 12 pesticide-treated hives in the current study experienced a 50% CCD mortality rate, the authors noted that, in their 2012 study, bees in pesticide-treated hives had a much higher CCD mortality rate—94%. That earlier bee die-off occurred during the particularly cold and prolonged winter of 2010-2011 in central Massachusetts, leading the authors to speculate that colder temperatures, in combination with neonicotinoids, may play a role in the severity of CCD.

“Although we have demonstrated the validity of the association between neonicotinoids and CCD in this study, future research could help elucidate the biological mechanism that is responsible for linking sub-lethal neonicotinoid exposures to CCD,” said Lu. “Hopefully we can reverse the continuing trend of honey bee loss.”
Sub-lethal exposure to neonicotinoids impaired honey bees winterization before proceeding to colony collapse disorder,” Chensheng Lu, Kenneth M. Warchol, Richard A. Callahan, Bulletin of Insectology, online Friday, May 9, 2014. Press release source.

from:    http://www.activistpost.com/2014/05/highly-likely-insecticides-triggered.html