Target shoppers in Wilsonville, Oregon found a tragedy in the parking lot as tens of thousands of of bumble bees were found dead and dying on the pavement, along with honey bees and ladybugs. Shoppers notified Rich Hatfield, a conservation biologist with the Portland-based Xerces Society of Invertebrate Conservation, who went to the scene to investigate.

Because the bees were mostly clustered under dozens of European linden trees, the organization believes the cause of the deaths likely involves acute pesticide poisoning or a poisonous species of European linden tree.

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