BROOKINGS, S.D. (AP) — A federal scientist says he was punished for publicizing research showing a link between pesticides and the decline in bees and other pollinators.

Brookings, South Dakota-based entomologist Jonathan Lundgren filed a whistleblower complaint against the U.S. Department of Agriculture on Wednesday. The complaint says Lundgren's research and work travel was scrutinized, and that he was suspended for violating agency protocols.

Lundgren is being represented by Public Employees for Environmental Responsibility in his complaint to a federal whistleblower protection board.

"Once he started publishing this work, he went from golden boy to pariah, and that's what this case is about," said Jeff Ruch, the group's executive director.

According to Ruch, Lundgren has worked with the USDA for 11 years and was highly regarded until he published a paper showing a class of insecticides called neonicotinoids is harmful to monarch butterflies. Lundgren's complaint says a supervisor confronted him about publishing about a "sensitive" without permission.

In August, Lundgren was suspended for two weeks without pay. A letter from a supervisor says Lundgren was suspended following a complaint by one of his lab employees, and because he falsified travel charges and didn't follow supervisor instructions, among other infractions.

Ruch claims pressure from the pesticide industry led the USDA to stifle Lundgren and other scientists. He doesn't have evidence, but said the complaint will allow attorneys to seek information and interview USDA officials.

USDA spokesman Christopher Bentley said the agency can't discuss individual cases, but said it's committed to scientific integrity. He said the agency reviews allegations of wrongdoing.

"The USDA has implemented a strong scientific integrity policy to promote a culture of excellence and transparency," Bentley said in a statement. "That includes procedures for staff to report any perceived interference with their work, seek resolution, and receive protection ... for doing so."

Lundgren filed an internal complaint in September 2014 that accused the USDA of retaliating against him because of his research. The agency found his complaint had no merit, and an appeal by Lundgren is awaiting a response from the agency.

Ruch said going public was a "last resort" for Lundgren.

"He's at the brink of professional elimination," Ruch said.