N.L.'s Atlantic salmon stocks still struggling, says DFO in latest assessment
The federal Department of Fisheries and Oceans Canada says Atlantic salmon stocks declined in most Newfoundland and Labrador rivers in 2022.
In its assessment of Atlantic salmon stock in 21 of the province's rivers in 2022, released Tuesday, the DFO said most rivers in Newfoundland saw "below-average returns" while Labrador rivers saw some improvements compared with average numbers over the previous five years.
Seventeen rivers in Newfoundland were monitored last season. Fifteen of those were assessed and two either weren't assessed or had no stock status designated.
Nine of the fifteen assessed rivers are in the "critical zone": less than or equal to 40 per cent of what DFO calls "biomass maximum sustainable yield" — the ideal total weight of the stock that maximizes how much can be fished sustainably — and there is likely serious harm occurring to the stock. One river is in the "cautious zone" — the biomass is between 40 and 80 per cent of the maximum sustainable yield.
Five rivers were deemed healthy.
Four rivers were assessed in Labrador last year. One is in the critical zone, one in the cautious zone and two are healthy.
"In 2021 we saw above-average returns, strong returns to most monitored rivers in the whole region. But this year, unfortunately, it kind of went down again, at least for the island portion of the province," said DFO salmon stock biologist Nick Kelly on Tuesday.
"We do see pretty strong declines on the south coast, particularly in the central portion of the south coast in the Bay d'Espoir region."
DFO said the survival and return of young salmon that go to sea continues to be the "major factor" limiting the stock's population.
The assessment says estimated survival on monitored rivers for 2022 was between 5.4 and 10.7 per cent, excluding Conne River and Garnish, where the survival rate was between 1.2 and 3.9 per cent.
Returns to Conne River were the third lowest on record since 1986, while Rocky River, Northeast River and Come By Chance River also saw below average returns.
Conner River would see about 8,000 to 10,000 salmon return to the river over 30 years ago. The stock has been consistently dropping since.
"The past three years in a row, fewer than 300 fish have returned," said Kelly.
"This spring, we're hoping to deploy a bunch of acoustic receivers in Bay d'Espoir, which are these foot-long cylinders that can detect tags, that have been planted in salmon, as they swim by. We're going track their migration and survival in Bay d'Espoir."
At the same time, Kelly said, other DFO scientists will be looking into the potential impacts of sea lice on salmon survival.
The DFO listed several factors having an impact on juvenile salmon returns, including changing ocean water temperatures — 2021 and 2022 were two of the warmest years on record — sea ice, changes in zooplankton and predation.
"When they're at sea it's a whole complex variety of factors that could be influencing their survival from year to year. It's something that all salmon researchers, on both sides of the Atlantic, are trying to get a better handle on," said Kelly.
"On the south coast potentially there's some implications from aquaculture activities on the wild populations."