A Canadian environmental activist who waged a sustained online campaign against two prominent marine scientists was found guilty of criminal harassment by a court in Victoria, British Columbia, on Thursday.

The court heard that Dana Durnford, 54, threatened violence against Jay Cullen, of the University of Victoria, and Ken Buesseler, of Woods Hole Oceanographic Institution in Massachusetts, and accused them of underplaying the extent of damage to Pacific ecosystems from the 2011 Fukushima disaster.

Durnford was sentenced to three years’ probation.

“I expected and was pleased with the judge’s ruling,” Cullen said after the verdict. “Mr. Durnford, on many occasions, threatened physical violence against scientists and others who have focused their attention and expertise to better understand how the Fukushima nuclear disaster has affected the marine environment and human health. Such behavior is criminal.”

Buesseler also welcomed the ruling. Threatening violence is “never an appropriate response to scientific findings you might disagree with,” he said.

Durnford, a former professional diver, has a large online presence.

His unscripted videos, recorded in a mock television studio, present what he purports to be research that contradicts mainstream scientific findings.

He alleges collusion between the global scientific establishment and the nuclear industry over the dangers presented by the nuclear industry and, in particular, the Fukushima debacle.

Durnford, of Powell River, British Columbia, did not respond to phone calls and an email for comment on Friday.

In a video apparently recorded shortly before the trial began this week, he alluded to trouble meeting court-related costs.

“They bankrupted us in these court proceedings in order to silence us,” he told viewers.