Aquatic Animals

Freshwater Fish Passage Barriers

Dams, culverts, and weirs block fish migration routes, causing population fragmentation and preventing access to spawning habitat.

Key Facts

Over 60% of large rivers are fragmented by dams globally
Salmon and trout require unobstructed access to upstream spawning grounds
Fish passage structures like ladders provide partial but incomplete solutions
Dam removal has dramatically restored fish populations in multiple river systems
Culverts under roads block millions of miles of fish habitat in the United States

Welfare Considerations

Fish blocked from spawning migrations experience behavioral frustration and ultimately fail to reproduce. Blocked passage concentrates fish in suboptimal habitat where disease spreads and predation increases. Dam removal, passage structure installation, and culvert replacement address this welfare problem while providing major ecological benefits.

What You Can Do

Support dam removal projects on fish-bearing rivers
Advocate for fish-passable culvert requirements in road projects
Donate to river restoration organizations
Support research on fish passage structure effectiveness
Engage with water management agencies about fish passage priorities