25,000 bumblebees turn up dead in Oregon parking lot

Oregon agricultural officials are investigating the death of an estimated 25,000 bumblebees at a Portland-area shopping mall.

Xerces Society for Invertebrate Conservation bee experts say the dead insects have piled up in the parking lot over the past few days, The Associated Press reported. They had been clustered under nearby linden trees.

The Oregonian reported that a recent insecticide spray could be to blame. State officials are testing the bees and will have toxicology reports ready in a couple days, AP said.

Meanwhile, pesticide company workers are wrapping the trees with bee-proof netting as a precaution, AP reported.