While N.L.'s murre population appeared healthy over winter, experts keeping close eye on avian flu

A deadly strain of avian influenza that swept through seabird colonies in Newfoundland and Labrador last summer and early fall is still a cause for concern heading into a new year, warns one expert.

Bill Montevecchi, a seabird biologist at Memorial University, said the province's colonies were "hammered" by the disease last year, resulting in the death of tens of thousands of birds of varying species, many of which washed up on coastal shores and beaches to the bewilderment of experts, hunters and bird enthusiasts. 

"We started out last April, we had this huge die-off of murres due to ice conditions on the southern Labrador coast. That took out, we're sure, thousands of birds and then right after that, it was in May when the virus started showing up on the west coast," Montevecchi said Monday.

"Then it went all summer. Tens of thousands of murres, the same for gannets as well. [It was] a huge impact and those will be the questions this summer as we go back to the colonies: will we see gaps or will those gaps be filled in by non-breeding birds?"

Montevecchi said the birds are resilient, but climate change, on top of the avian flu, is compromising the populations. 

He said experts are hoping for the best this summer but are remaining realistic as they watch the colonies closely. 

"That mortality from the spring event and the mortality from the virus, these are unprecedented. It has never happened at that level before," he said. 

"And it's ongoing because, like COVID, the expectation is that the birds will still be carrying some of that virus and the question is will it be lethal or what will be the consequences." 

Montevecchi said it's difficult to predict how the seabird populations will fare this summer.

The first cases of avian influenza were tracked to the Cape St. Mary's Ecological Reserve in early June. Montevecchi said scientists were "terrified" it would wipe out the colony. 

But the hit to the population didn't happen until late July, he said, and experts still don't have an answer as to why. 

"The water temperature heated up abnormally, such that we had a heat wave by the end of July, and we think — we can't prove it — maybe that added stress of the hot water that made it hard for the parents to get food for their young, they're carrying the virus and that the stress just put them over the edge," Montevecchi said.

"It depends on a combination of things. It seems like the animal sometimes could have the virus and survive but if the situation is stressful it might just push the bird over the edge. It's that really complex combination of things that will determine how it plays out."

But the winter showed some positive signs for the murre population.

Montevecchi said there was a reduction in the annual winter hunt in terms of the amount of people actively partaking in the event.

He said many hunters didn't go out of concern the virus still lingered, but those who did hunt reported healthy birds. 

"Basic reports that came back from hunters was that one, there were a lot of birds and the birds were all in good condition, and also Environment Canada, to my understanding, has been testing these birds for the virus and has yet to pick up any positive signs of the virus," said Montevecchi.

"So it looks like there was a reduction in the hunt, which would give the murres a reprieve, and the hunters who did hunt seemed to do well seemed to do well, got good birds and the birds, as best we can tell, seemed to be healthy. What happens this summer when the weather warms up, that remains to be seen."

Meanwhile, the two resident swans of Bowring Park in St. John's along with seven ducks have died, the city confirmed in a statement Friday, adding it believes the cause of death was avian influenza. 

"The young swan appeared to be sick and died quickly; one week later the older swan was found dead in the duck pond [in] Bowring Park," the statement reads. "The older swan, along with seven ducks found dead in the pond, have been sent away for testing and appear to have died of avian flu."

The city is asking the public to refrain from feeding the birds in Bowring Park, noting there are several signs on site discouraging the act but people are still doing it.

"We ask individuals to please stop feeding birds. As long as the practice continues, we are concerned that we will see more fatalities," reads the city's statement. 

"We have discussed these deaths with those responsible for tracking, testing and monitoring avian flu. They have advised that avian flu is increasing in the area, so mortality is to be expected."

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