TECH

No answers in mystery Oregon bee deaths

Tracy Loew
Statesman Journal

No pesticides were found in bees collected from four Clackamas County sites where entire colonies were found dead in June, the Oregon Department of Agriculture announced Monday.

Previous tests for disease and viruses also showed nothing that would explain the mass die-offs.

"We're really left without any concrete evidence of what affected those particular hives," said Dale Mitchell, ODA pesticides program manager.

DOCUMENT:Report of Lab Analysis

Beekeepers began noticing thousands of dead bees in and around their hives on June 18.

ODA officials collected hundreds of bees from each site, but didn't test them immediately because no particular pesticide was identified as likely, and testing for all known ingredients would have overwhelmed the state laboratory.

Instead, staffers worked to develop a comprehensive screen of 39 pesticide active ingredients that are commonly used in Oregon and can harm bees. That screen will be used for any future bee die-offs.

The department completed the tests on Friday, ODA spokesman Bruce Pokarney said.

RELATED: Mass bee die-offs continuing in Oregon

Oregon State University also tested for viruses and diseases. Those tests showed nothing that would explain the sudden deaths.

Dena Rash Guzman was the first to report bee deaths, on the Sandy-area farm where she keep hives.

"I appreciate the state's diligence and investigation," she said. "But I still find it curious that all of these hives dropped dead on the same day. I really think that something is wrong."

ODA has not received any further reports of colony deaths.

The state will close its investigation, which cost thousands of dollars, Mitchell said.

"We really cannot say definitively what affected those hives of those individuals," he said.

ODA continues to work on issues of bee health, he said, including working with a legislative task force studying the issue.

tloew@statesmanjournal.com, (503) 399-6779 or follow at Twitter.com/SJWatchdog