Freshwater Wildlife

Aquatic Invertebrate Welfare and Agricultural Chemical Pollution

Aquatic invertebrates including water boatmen, freshwater shrimps, and mayfly larvae are highly sensitive to agricultural chemicals. Their welfare and ecological function are foundational to healthy freshwater ecosystems.

Key Facts

Aquatic invertebrates are used as bioindicators of river health in UK monitoring systems
Freshwater shrimps (Gammarus) are among the most pesticide-sensitive invertebrates in UK rivers
Mayflies, stoneflies, and caddisflies require very clean water to complete their life cycles
Agricultural pesticide runoff events cause acute mass mortality of invertebrate communities
Recovery from pollution events can take years and requires recolonisation from surviving populations

Welfare Considerations

While the sentience of aquatic invertebrates is scientifically uncertain, precautionary welfare consideration is warranted given their complexity and the scale of mortality events. Mass mortality of river invertebrates represents enormous numbers of animals dying in distress. The ecological consequences affect all species in the food web, from fish to water shrews to kingfishers.

What You Can Do

Support Riverfly Partnership monitoring to detect invertebrate declines early
Advocate for rigorous enforcement of the Water Framework Directive
Donate to Rivers Trusts catchment restoration work
Support organic farming and agri-environment schemes that reduce chemical runoff
Contact your water company about their catchment management investments