Visual Stories

Photos: Lower Russian Lake fish weir

What the heck's a weir, anyway?

"It's French for fence," explained Alaska Department of Fish and Game Area Management Biologist Robert Begich.

Put simply, the fish weirs used by the department are typically long aluminum dam-like grates that extend the width of a river or creek to impede fish passage. Salmon migrating upstream to spawn are trapped behind the structure, which includes a small door through which technicians can allow fish to move through one at a time. This lets workers click off each fish on hand counters as the salmon pass.

Read more: Low-tech but precise, Russian River weir helps technicians count thousands of Alaska salmon one by one

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