Plastic pollution in marine and freshwater environments causes direct welfare harm to millions of individual animals annually through entanglement, ingestion, toxic contamination and habitat degradation.
Marine plastic pollution causes welfare harm through multiple mechanisms operating at scales from individual entanglement to population-level toxic contamination. An entangled seal or sea turtle experiences progressive injury and restriction that may continue for months before death or rescue. A seabird chick fed plastic by parents misidentifying it as food experiences gastrointestinal obstruction and starvation. A fish ingesting microplastics receives toxic chemical loads and experiences false satiety that reduces nutritional intake. The welfare costs are real, widespread and increasing. Addressing them requires both individual rescue responses and systemic change in plastic production, use and disposal. Consumer and policy action on plastic reduction is simultaneously an environmental and animal welfare priority.