Warm weather blamed for millions of moths invading New Brunswick

Moth swarms

Thanks to the warm weather, parts of New Brunswick have been blanketed with millions of tiny moths.

The infestation is so bad, in fact, that the insects actually appeared on Environment Canada’s weather radar.

“You can actually see the radar imagery of these big plumes on non-precipitation nights, big plumes of something moving down from the north,” Rob Johns, an insect ecologist with National Resources Canada, told CBC News.

He says the massive influx of spruce budworm moths, which have carpeted parking lots and cars in the Campbellton-Dallhousie area, is likely due to warm weather, which tends to cause updrafts that allow the moths to be pulled up into the atmosphere.

Photo by Mathieu LeClair

“They can be carried hundreds of kilometres away,” he said, adding that they’ve had reports of them as far south as Saint John and Shediac. He says the insects are likely coming from the the Baie Comeau of Quebec area, which is currently experiencing an outbreak.  

According to the Healthy Forest Partnership, the spruce budworm has been one of the most destructive insects in eastern Canada’s forests. These insects’ larvae feed on new needles of balsam fir and spruce trees, and can cause severe damage to their branches. In fact, millions of hectares of trees can be defoliated by an outbreak, which is exactly what happened in New Brunswick in the ’70s and ’80s, and in Quebec a decade ago.

Photo by Mathieu LeClair

Although scientists have been warning of another spruce budworm outbreak, Johns says that these swarms don’t necessarily mean that’s going to happen. He told CBC that his crew is currently digging through the moths that are hanging out in parking lots and on shrubs, and have found that a huge percentage are male, “which of course are not carrying eggs.”

But with forests at risk, it’s important to be vigilant and keep tabs on the insects, ensuring they don’t spread any further. The public is being advised to check fir and spruce trees for redness and defoliation. They can also collect any moths they find and arrange for them to be picked up.

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