How does a fish ladder at a dam help salmon populations?
The purpose of a fish ladder, or fishway, is to help migrating fish navigate past dams that would otherwise block access to spawning habitat.
What are disadvantages to fish ladders?
Fish ladders such as pool and weir may be effective but come at energy cost which is not always the most efficient for all species and may reduce the capacity of a fish to reach its spawning grounds.
Do fish ladders help salmon?
Salmon migrating upriver often encounter blockages and obstructions they need to circumvent. The implementation of fish ladders alongside large dams have provided salmon with a way to forge ahead, though they still face the challenge of locating, entering, and traversing these fishways.