High Water Temperatures Threaten Newfoundland’s Salmon Population

High water temperatures and reduced water levels are significantly impacting the Atlantic salmon population in Newfoundland and Labrador. According to the latest report from Fisheries and Oceans Canada (DFO), over 60 percent of the province’s salmon rivers remain in the critical zone. This decline is alarming, with predictions indicating that the number of young salmon affected by these conditions could further decrease returns over the next five to six years.

Nick Kelly, a salmon stock assessment biologist with DFO, expressed concern during a press briefing on Friday. He explained that as water levels drop, temperatures can increase rapidly. “Once water levels drop, temperature can go up much faster,” Kelly stated. He noted that the 2025 salmon stock assessment shows a continued downward trend, following historic lows that have been observed since 2023. Specifically, 62 percent of assessed rivers in Newfoundland are categorized as being in the critical zone.

Current Conditions and Historical Context

The situation is particularly dire in southern Labrador, where one of three assessed rivers is also listed as critical. The other two rivers in the region are stable, while the northern Labrador river monitored is experiencing positive returns and is classified as healthy. This year’s low water levels are attributed to limited snowmelt and drought conditions in July and August, which have compounded the challenges for salmon populations.

Kelly reported that these adverse conditions have led to mortality events in seven freshwater rivers, including well-known locations such as Middle Brook, Placentia Bay, and Point Leamington. While the overall fatalities were low, the Conne River faced a notable exception. Once home to as many as 10,000 returning salmon each year during the 1980s, the river has seen a drastic decline. This year, only about 585 fish returned, with at least 100 reported deaths.

During a particularly severe week in July, multiple rivers experienced spikes in temperature, with river temperatures reported in the high 20s Celsius, approaching lethal limits for salmon. “Within the same span of about a week or so in July, we had a lot of these mortality events on a bunch of different rivers on the island,” Kelly explained.

Industry and Future Monitoring

The salmon farming industry is also facing challenges, with similar die-offs reported at various farms across Newfoundland this fall. Kelly emphasized that salmon populations are under ongoing threat, particularly as fewer smolts make their way to sea each year. This decline could lead to even smaller returns in the future.

Fisheries and Oceans Canada plans to continue monitoring the impacts on salmon populations closely. Kelly confirmed that a management plan for the 2026 season will incorporate the latest assessments along with insights from stakeholders and socioeconomic factors.

The situation remains critical for Newfoundland’s salmon population, highlighting the urgent need for effective management strategies in response to climate-related challenges.