For years, scientists have suspected that a strain of pesticides called neonicotinoids was behind the worldwide decline in bee populations.

Wherever it was sprayed, bee populations seemed to decline. But disentangling the pesticide from other environmental factors proved difficult. Now, however, scientists may have pinpointed their effect — neonicotinoids cause bees to stop reproducing, according to a groundbreaking study out of the UK.

Bees play a critical role in global agricultural by pollinating crops, and their protection is a target of both Global Goal 2, food and hunger, and Global Goal 15, life on land. Global Citizen campaigns to achieve the UN’s Global Goals, and you can take action on them here.

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This new research could end up helping bees by influencing environmental regulations around the world.

To find the link between neonicotinoids and bee health, a team of scientists at the Royal Holloway University of London fed one group of queen bees a type of syrup and another group of bees the same syrup, except with traces of the pesticide.

This is similar to how bees would encounter the pesticide in nature, because when neonicotinoids are sprayed they become systemic to the plant, entering the plant’s roots, flowers, and showing up in pollen, according to Huffington Post.

They found that the bee group exposed to the pesticide were 26% less likely than the control group to reproduce.

The bees in the study were wild bees, not honey bees, but the findings could have meaning for all species of bee.  

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"Without the queen laying eggs, there is no colony," Nigel Raine, one of the scientists who conducted the experiment, told Huffington Post.

He told the news site that bees exposed to the pesticide “could enter a spiral of decline and eventually die out.”

The European Union issued a moratorium on neonicotinoids in 2013 to conduct further research into their effects on bees.

Since then, farming groups have lobbied for the pesticide class to be reintroduced because it boosts crop yield.

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The new research could give the EU the grounding it needs to outlaw the pesticide once and for all, ushering in a victory for those seeking to protect bees.

In the US, the Environmental Protection Agency has blocked certain neonicotinoids when bees are present and is investigating whether the full class should be allowed.

Still, Raine warned against blaming the worldwide decline of bees on this neonicotinoids alone. Globally, 37% of bee species are facing population loss, according to the UN. In the US, around 50% of species are declining and nearly 25% are facing extinction.

The reasons for this decline are likely varied and could include factors such as climate change, deforestation, loss of wildflowers, loss of crop diversity, the growth of bee-killing pests, the growth of diseases, and more, according to extensive surveys of bee populations.

In the US, one in three bites of food are linked to bee pollination. So ensuring their future health goes beyond making sure honey can still be found.


Defend the Planet

Bees Face ‘Spiral of Decline’ Because of Toxic Pesticide

By Joe McCarthy