How Salmon are Adapting to Climate Change
With warming ocean, river, and stream temperatures, wild salmon have been forced to adapt quickly. They’ve evolved over millions of years to make it here, so they’re resilient animals. However, wild salmon now face immense environmental and evolutionary pressures, causing their populations to rapidly decline.
The wild salmon that do survive have adapted by doing these things:
- Migrating further north where waters aren’t as warm. Both Atlantic and Pacific wild salmon have been observed moving northward.
- Migrating from the ocean to rivers earlier in the year. Salmon DNA reveals that nature now selects for salmon migrating earlier, meaning it’s an evolutionary response to climate change.
- Remaining in cooler pools of water until ocean or river temperatures become safe enough for the salmon.
We Can Also Help Salmon Adapt
Various officials have mentioned several mitigation strategies to reduce the impacts of climate change on wild salmon. Some of these strategies include:
- Installing water temperature monitors in rivers to help locate hot spots. In Nova Scotia, officials have installed these monitors in the Margaree and Mabout Rivers, for example. If the monitors record high temperatures, work crews will plant trees along the rivers to provide shade for wild salmon.
- Diverting the flow of rivers to create larger pools of cold water. This provides shelter from extreme heat for salmon swimming upstream.
- Replacing culverts and road crossings with alternatives so that salmon can access previously blocked areas. This will expand their habitat and open up new areas for them to spawn.
- Employing fish rescue programs to provide assisted migration for salmon. In some areas of the Pacific Northwest, wild salmon are already transported past dams and weirs so they can make it upstream. Also, when stream levels dip too low, fish rescue programs assist the fish into waterways with higher flow.
Final Thoughts on Saving the Wild Salmon in Scotland
Across the globe, salmon populations face imminent threats from climate change, habitat destruction, and other human-caused factors. However, some humans have come to their rescue in order to preserve the species that cultures around the world rely on. Some strategies they’ve employed include planting trees along rivers to provide shade, diverting water in rivers to increase flow, and removing culverts to increase habitat. Hopefully, we will see a large increase in salmon populations as a result of these efforts.