The Chinook salmon on the Klamath River have made a stunning recovery, reclaiming nearly 90% of their historic upper basin habitat within just two years following the world’s largest dam removal, highlighting a significant ecological triumph.
- Chinook salmon regained 88% of historic habitat in two years
- Four century-old dams removed in the largest global dam removal
- Recovery aided by gentle terrain and cold, spring-fed rivers
What happened
In October 2024, crews completed removing four hydroelectric dams on the Klamath River, which had obstructed salmon migration for over 100 years. These dams, located along the Oregon-California border, kept migratory Chinook salmon from accessing their historic spawning grounds in the upper basin. Scientists have now confirmed that within two years, Chinook salmon recolonized about 88% of that previously blocked territory.
Researchers used underwater sonar cameras to monitor fish passage, documenting an increase from roughly 7,700 Chinook crossing the former dam sites in 2024 to more than 13,000 in 2025. This rapid recolonization not only signifies the success of this historic project but also places the Klamath River among the most successful dam removal recoveries ever recorded.
Why it feels good
The Klamath River salmon comeback resonates as a hopeful sign of nature’s resilience when human-made barriers are removed. Salmon populations had dramatically declined due to dams, overfishing, and water withdrawals, with losses exceeding 90% at their worst. The vibrant return of Chinook salmon symbolizes progress not only for the species but for the ecosystems and communities connected to the river.
This ecological restoration also honors the cultural and subsistence importance of Chinook salmon for local tribal nations including the Yurok, Karuk, Klamath, and Shasta. Their sustained advocacy for dam removal was crucial in making this recovery possible, showing how collaboration between indigenous groups and environmental efforts can lead to transformative outcomes.
What to enjoy or watch next
The recovery extends beyond Chinook salmon; species such as coho salmon, steelhead, and Pacific lamprey have also been spotted exploring the restored river sections, though their populations remain smaller. This broader resurgence indicates growing biodiversity and healthier river ecosystems. Ongoing monitoring will track these species’ responses and the durability of the habitat improvements.
Looking ahead, the Klamath River serves as an inspiring model for similar restoration projects worldwide. The gentle terrain of the upper basin and cold, spring-fed waters have helped speed recolonization, providing valuable lessons for other rivers where dam removals might unlock ecological recovery and cultural renewal.