Spruce budworm findings fuel concern over possible outbreak

Scientists at Natural Resources Canada say that about 80 per cent of the spruce budworm moths they collected after a migration event in the Campbellton-Dalhousie area last month were female.

Millions of the moths descended on the area covering parking lots, gas stations and cars in the northern communities.

Rob Johns, an insect ecologist with Natural Resources Canada, said his crews have gone through about 1,000 of the moths so far.

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When they started looking at the samples, he said they didn't expect that nearly 800 of them would be female.

Those are "moths that could be carrying eggs, that could potentially deposit those eggs in a very broad scale area and could potentially be a problem," Johns said.

Spruce budworm caused massive defoliation in the province in the 1970s and '80s.

It has been on a downward trend since that time, but in the past few years scientists have begun warning of another serious outbreak.

There is a spruce budworm outbreak in Quebec that is infesting millions of hectares of trees.

Johns said the outbreak is moving closer to the border between Quebec and New Brunswick.

Budworm activity

Johns said they have been surveying the area and have found spruce budworm activity in the forests.

"We have a little bit of defoliation around Bathurst that suggests there's some small populations there. We found eight masses there, which is not completely unexpected," he said.

Johns added that most of the effects from this mass migration event are probably localized to that area.

"It's still really patchy, you can find lots of branches that have nothing, but we have a couple branches where we found that have 20 to 28 egg masses," he said.

Each egg mass carries as many as 20 eggs, John said.

"So that would come from multiple females laying eggs and these are in areas where there's no previous defoliation, at least from this past year, and no pupil casing to suggest budworm is present there," he said.

There are still more branches that need to be processed before researchers will fully understand the extent of the spread.

"This is part of the management strategy were working with now," he said.

"So really the next biggest, most important step right now is to do a bit of number crunching and do our surveys and make decisions around where we think these hot spots might be creeping up and working actively and proactively to manage those."