Welfare of Animals in Freshwater Fish Biodiversity

Freshwater fish are the most threatened vertebrate group globally, with individual and population welfare affected by pollution, dams, invasive species, and climate change.

Key Facts

Freshwater fish represent approximately 50% of all fish species despite freshwater comprising only 0.01% of global water
One in three freshwater fish species is threatened with extinction
Freshwater biodiversity loss is occurring faster than marine or terrestrial biodiversity loss
River fish experience welfare harm from oxygen depletion, chemical pollutants, and barrier impacts on migration
Native freshwater fish welfare is further compromised by invasive species that predate and compete with them

Welfare Considerations

Freshwater fish welfare is a largely invisible crisis: the rivers and lakes that support thousands of endemic fish species are being degraded simultaneously by nutrient pollution, chemical contamination, dam construction, and water extraction. Individual fish in oxygen-depleted water experience hypoxia stress; those blocked from spawning habitat by dams cannot fulfill reproductive imperatives; those competing with invasive predators face higher predation risk. River restoration — removing dams, restoring riparian vegetation, reducing agricultural runoff — is the most welfare-positive intervention at landscape scale.

What You Can Do

Support American Rivers dam removal campaigns for priority river restoration
Reduce fertilizer and chemical use in your garden to protect local waterway water quality
Donate to Freshwater Habitats Trust programs protecting priority freshwater fish habitats
Engage with local water management authorities about discharge quality standards protecting river fish welfare