Environmental conditions informing salmon returns in 2024

January 30, 2024

By: Meghan Rooney

Earlier this month, Watershed Watch staff participated in a well-attended update by DFO staff on anticipated salmon returns in 2024 and how environmental conditions in recent years may impact returns. This is part one of a two-part recap of DFO’s 2024 Salmon Outlook.

(Note: the DFO update did not cover steelhead as they are managed by the Province of B.C. rather than DFO. However, they face the same challenges as the salmon species discussed below.)

Who’s coming home in 2024? (It’s a bit complicated.)

While we know members of all five species of salmon will be returning to spawn in some capacity this year, the environmental conditions they have had to endure through their life cycles will be varied due to different age types and life histories. Depending on the species, salmon laid as eggs between 2019 and 2022 will be returning to spawn in 2024. These fish occupied marine and freshwater habitats in differing years.

Meghan Rooney

The image below provides greater detail on the salmon returning in 2024 and what years they were in freshwater or marine habitats.

Freshwater 

When it comes to freshwater habitats, conditions were quite varied between 2019 and 2023, but the general trend has been that conditions have worsened in recent years. 

In 2019, a spring heatwave triggered early snow melt. However, drought was mitigated by a very wet July. 2019 also was not a tough year for wildfires, however, 2017 and 2018 were and this could have resulted in increased sedimentation or slope destabilization in certain salmon-bearing waterways in regions that were burned.

Overall, freshwater conditions in 2019 were good for wild salmon, which would include Chinook and sockeye that will be returning this year, laid as eggs in the latter half of 2019.

In 2020, B.C. again experienced an early heatwave that triggered snowmelt in many regions, particularly Vancouver Island and the South Coast. Wildfire season was also minimal in 2020. Due to this, overall freshwater conditions were good for salmon, though some specific regions experienced higher levels of drought. Overall, conditions would have benefited sockeye and Chinook juveniles that remained in freshwater habitats to rear, as well as eggs of Chinook, sockeye and chum laid that year that will be returning in 2024.

2021 was the year B.C. experienced its deadly heat dome. While we started off with good snowpack levels, following the June heatwave the province experienced severe drought, particularly in the Okanagan, South Coast and on Vancouver Island, that would have posed problems for salmon returning to spawn. Low flows and high water temperatures that resulted would have impacted rearing sockeye and Chinook juveniles and sockeye, coho and chum salmon eggs that were laid that year. 2021 was also a worse year for wildfires in B.C., though it pales in comparison to the wildfire season of 2023.

2021 was also the year the South Coast of B.C. experienced significant flooding following atmospheric rivers, which was thought to have scoured out redds containing recently laid salmon eggs. The good news is pink salmon returns last year to the Fraser were better than anticipated, despite concerns they would have been impacted by flood events. Hopefully, this bodes well for other salmon populations that may have also been affected and will be returning in 2024. 

2022 started similarly to 2021 with average snowpacks, however, we experienced an extremely dry summer and fall in B.C. with a lack of precipitation persisting into November. Wildfire season was mild in 2022 but persistent drought created very difficult conditions for returning spawners in many systems. We will have to wait to see how it will affect returns for other salmon species, but pink salmon laid as eggs in 2022 will be returning this year (though even-numbered years for pink returns are non-dominant and returns are expected to be low, regardless).

Credit: Tavish Campbell

Marine Conditions

It’s not just freshwater conditions that have been in flux – marine conditions also changed between 2019 and 2022. A mild El Niño transitioned to a moderate La Niña in 2020, which weakened through 2022 before transitioning back to El Niño in 2023.

As presenter Dr. Sue Grant noted, as the planet warms, La Niña is starting to look like El Niños of the past.

While La Niña is typically associated with cooler ocean temperatures, which benefit B.C. salmon, the positive effects of La Niña are being reduced by warming ocean temperatures triggered by human-caused climate change. As noted by the U.S.A.’s National Oceanic and Atmospheric Administration, four ocean heat waves between 2019 and 2022 were the 2nd, 3rd, 6th and 4th largest marine heatwaves since records were started in the 80’s.

Warmer ocean temperatures are altering ocean food webs. Smaller, less nutritious zooplankton becoming more prevalent than their larger, more nutritious counterparts that are an important food source for wild salmon.

For salmon returning this year, generally, La Niña helped moderate conditions for B.C. salmon runs but recurring, severe ocean heat waves are counteracting these positive effects.

Our takeaways

Conditions in both freshwater and marine habitats are trending in the wrong direction for B.C. salmon. While actions to improve warming marine habitats will require worldwide action and will take time to see the effects of, we can reduce other impacts felt by wild salmon in the marine environment to improve returns, such as getting fish farms out of migration routes and stopping Alaskan interception of B.C.’s wild salmon.

There is much that can and should be addressed for freshwater habitats. While the provincial government has taken steps to improve how B.C. manages freshwater, decision-making around land and water needs to be integrated – we must be thinking and planning at a watershed scale. We need decision-makers to recognize the value of healthy watersheds, not only to maintain culturally, ecologically and economically important species such as salmon, but also to sustain local agriculture, mitigate the impacts of fires, floods, droughts and climate change, and so much more.

This means greater investments to secure and restore watersheds across the province. We need better planning, resources and policies in place so we can be proactive in the face of challenges, such as drought, instead of reactive. Restoring riparian habitats, improving habitat connectivity and maintaining minimum flow requirements will mean fewer fish kills and fewer fish salvages.

With low snowpacks and a persistent drought starting off the year, 2024 may prove to be a tough year for wild salmon. As we will cover in more detail in part two, returns in many regions of our province are expected to be at or below average.

If you want to take action to help wild salmon, please consider writing the premier, water minister and your MLA to help advance fresh water security in B.C.

Share This Story!

Environmental conditions informing salmon returns in 2024

January 30, 2024

By: Meghan Rooney

Earlier this month, Watershed Watch staff participated in a well-attended update by DFO staff on anticipated salmon returns in 2024 and how environmental conditions in recent years may impact returns. This is part one of a two-part recap of DFO’s 2024 Salmon Outlook.

(Note: the DFO update did not cover steelhead as they are managed by the Province of B.C. rather than DFO. However, they face the same challenges as the salmon species discussed below.)

Who’s coming home in 2024? (It’s a bit complicated.)

While we know members of all five species of salmon will be returning to spawn in some capacity this year, the environmental conditions they have had to endure through their life cycles will be varied due to different age types and life histories. Depending on the species, salmon laid as eggs between 2019 and 2022 will be returning to spawn in 2024. These fish occupied marine and freshwater habitats in differing years.

Meghan Rooney

The image below provides greater detail on the salmon returning in 2024 and what years they were in freshwater or marine habitats.

Freshwater 

When it comes to freshwater habitats, conditions were quite varied between 2019 and 2023, but the general trend has been that conditions have worsened in recent years. 

In 2019, a spring heatwave triggered early snow melt. However, drought was mitigated by a very wet July. 2019 also was not a tough year for wildfires, however, 2017 and 2018 were and this could have resulted in increased sedimentation or slope destabilization in certain salmon-bearing waterways in regions that were burned.

Overall, freshwater conditions in 2019 were good for wild salmon, which would include Chinook and sockeye that will be returning this year, laid as eggs in the latter half of 2019.

In 2020, B.C. again experienced an early heatwave that triggered snowmelt in many regions, particularly Vancouver Island and the South Coast. Wildfire season was also minimal in 2020. Due to this, overall freshwater conditions were good for salmon, though some specific regions experienced higher levels of drought. Overall, conditions would have benefited sockeye and Chinook juveniles that remained in freshwater habitats to rear, as well as eggs of Chinook, sockeye and chum laid that year that will be returning in 2024.

2021 was the year B.C. experienced its deadly heat dome. While we started off with good snowpack levels, following the June heatwave the province experienced severe drought, particularly in the Okanagan, South Coast and on Vancouver Island, that would have posed problems for salmon returning to spawn. Low flows and high water temperatures that resulted would have impacted rearing sockeye and Chinook juveniles and sockeye, coho and chum salmon eggs that were laid that year. 2021 was also a worse year for wildfires in B.C., though it pales in comparison to the wildfire season of 2023.

2021 was also the year the South Coast of B.C. experienced significant flooding following atmospheric rivers, which was thought to have scoured out redds containing recently laid salmon eggs. The good news is pink salmon returns last year to the Fraser were better than anticipated, despite concerns they would have been impacted by flood events. Hopefully, this bodes well for other salmon populations that may have also been affected and will be returning in 2024. 

2022 started similarly to 2021 with average snowpacks, however, we experienced an extremely dry summer and fall in B.C. with a lack of precipitation persisting into November. Wildfire season was mild in 2022 but persistent drought created very difficult conditions for returning spawners in many systems. We will have to wait to see how it will affect returns for other salmon species, but pink salmon laid as eggs in 2022 will be returning this year (though even-numbered years for pink returns are non-dominant and returns are expected to be low, regardless).

Credit: Tavish Campbell

Marine Conditions

It’s not just freshwater conditions that have been in flux – marine conditions also changed between 2019 and 2022. A mild El Niño transitioned to a moderate La Niña in 2020, which weakened through 2022 before transitioning back to El Niño in 2023.

As presenter Dr. Sue Grant noted, as the planet warms, La Niña is starting to look like El Niños of the past.

While La Niña is typically associated with cooler ocean temperatures, which benefit B.C. salmon, the positive effects of La Niña are being reduced by warming ocean temperatures triggered by human-caused climate change. As noted by the U.S.A.’s National Oceanic and Atmospheric Administration, four ocean heat waves between 2019 and 2022 were the 2nd, 3rd, 6th and 4th largest marine heatwaves since records were started in the 80’s.

Warmer ocean temperatures are altering ocean food webs. Smaller, less nutritious zooplankton becoming more prevalent than their larger, more nutritious counterparts that are an important food source for wild salmon.

For salmon returning this year, generally, La Niña helped moderate conditions for B.C. salmon runs but recurring, severe ocean heat waves are counteracting these positive effects.

Our takeaways

Conditions in both freshwater and marine habitats are trending in the wrong direction for B.C. salmon. While actions to improve warming marine habitats will require worldwide action and will take time to see the effects of, we can reduce other impacts felt by wild salmon in the marine environment to improve returns, such as getting fish farms out of migration routes and stopping Alaskan interception of B.C.’s wild salmon.

There is much that can and should be addressed for freshwater habitats. While the provincial government has taken steps to improve how B.C. manages freshwater, decision-making around land and water needs to be integrated – we must be thinking and planning at a watershed scale. We need decision-makers to recognize the value of healthy watersheds, not only to maintain culturally, ecologically and economically important species such as salmon, but also to sustain local agriculture, mitigate the impacts of fires, floods, droughts and climate change, and so much more.

This means greater investments to secure and restore watersheds across the province. We need better planning, resources and policies in place so we can be proactive in the face of challenges, such as drought, instead of reactive. Restoring riparian habitats, improving habitat connectivity and maintaining minimum flow requirements will mean fewer fish kills and fewer fish salvages.

With low snowpacks and a persistent drought starting off the year, 2024 may prove to be a tough year for wild salmon. As we will cover in more detail in part two, returns in many regions of our province are expected to be at or below average.

If you want to take action to help wild salmon, please consider writing the premier, water minister and your MLA to help advance fresh water security in B.C.

Share This Story!

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One Comment

  1. Leona Marie Antoine February 6, 2024 at 2:32 pm - Reply

    Thanks for the information. I wonder if salmon will adapt to other tributaries that are cooler, knowing that existing migratory route water is minimal quality and quantity. Be interesting to gauge that. I wonder too about the Big Bar landslide impact.

    Steelhead I hope will be managed more effectively with a new Ministry shuffle.

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