Exposure to even low levels of herbicides hinders bees' ability to forage from common wild flowers

Wednesday, April 06, 2016 by: S. Johnson
Tags: bee colonies, population decline, herbicides

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(NaturalNews) Bees are important, not just for their ability to churn honey, but for our very livelihood. Without bees, we wouldn't be here. And yet, bees are in trouble. According to a recent study co-authored by a University of Guelph professor, even low levels of herbicides can affect the foraging abilities of bumblebees to extract nectar and pollen.

Both wild and domestic honey bees account for approximately 80 percent of global pollination. Just one bee colony can pollinate 300 million flowers in a day. Greenpeace estimates that 70 of the top 100 human food crops are pollinated by bees, and these crops represent about 90 percent of the world's nutrition supply.

Albert Einstein noted that if the bees were to vanish from the face of the Earth, mankind would face extinction. Unfortunately, Einstein's warning has not been taken seriously enough. The worldwide bee colony is collapsing, thanks to habitat loss and the use of herbicides.

Bumble trouble

In the resent study, published in the journal Functional Ecology, researchers sought to analyze the impact of low levels of herbicides on bee production. Bumblebees were exposed to common levels of a neonicotinoid insecticide known as thiamethoxam. The study was the first to investigate the impact pesticides have on bumblebees' ability to forage from common wild flowers with complex shapes.

The researchers found that it took herbicide-exposed bees longer to collect pollen from a different flower than controlled bees. In addition, the pesticide-exposed bees decided to forage from a different flower than the controlled bees.

"Bees rely on learning to locate flowers, track their profitability and work out how best to efficiently extract nectar and pollen," said environmental sciences professor and senior author of the paper, Nigel Raine.

"If exposure to low levels of pesticide affects their ability to learn, bees may struggle to collect food and impair the essential pollination services they provide to both crops and wild plants," he added.

Previous studies have verified that exposure to neonicotinoid herbicides can alter the chemistry of the brain, particularly in areas linked to memory and learning in honeybees. In the recent study, herbicide-exposed bumblebees collected more pollen than control bees, but the control bees were able to learn how to extract nectar from intricate flowers after a few visits.

Lead author, Dara Stanley, of Royal Holloway University in London, told sources, "Bumblebees exposed to pesticide initially foraged faster and collected more pollen. However unexposed bees may be investing more time and energy in learning. Our findings have important implications for society and the economy as pollinating insects are vital to support agriculture and wild plant biodiversity."

Adding to these remarks, Raine said that more realistic field research is needed into the relationship between herbicides, bumblebees and other wild pollinators.

"Our results suggest that current levels of pesticide exposure could be significantly affecting how bees are interacting with wild plants, and impairing the crucial pollination services they provide that support healthy ecosystem function," he said.

In other words, if herbicides hinder bumblebees' ability to learn and adapt, then wild bees could become increasingly sensitive to changes in the environment. According to a separate review, an estimated 57 different herbicides are poisoning European honey bees, which is contributing to the rapidly declining bee population worldwide.

What can be done?

In 2013, Europe enforced an unprecedented two year continent-wide ban on three neonicotinoid herbicides believed to harm bees. Unfortunately, the U.S. has failed to make similar strides in protecting the bee population. In 2014, President Obama signed the Monsanto Protection Act, which gave biotech companies immunity from the havoc their commercial compounds wreak on people and the environment in federal U.S. courts.

Although the nature of the problem is complex, the solution is simple. The global bee population can be restored by banning dangerous herbicides, and preserving wild bee habitats. If such practices aren't put in place, bees won't be the only species to bear the sting of extinction.

Sources include:

ScienceDaily.com

Phys.org

TechTimes.com

GreenPeace.org

DailyMail.co.uk

TheGuardian.com

Science.NaturalNews.com