Grey herons and great blue herons navigate complex welfare challenges in agricultural landscapes including fishing line entanglement, lead contamination, and persecution at fish farms.
Heron welfare in human-modified landscapes involves both entanglement hazards and deliberate persecution. Fishing line injuries cause prolonged suffering as birds with damaged wings slowly lose condition. Lead contamination from fishing weights causes neurological impairment before death. Persecution at fish farms kills birds whose foraging at aquaculture sites reflects their natural behavior in habitat now dominated by fish-filled ponds. Non-lethal deterrents at fish farms — netting, wire, acoustic deterrents — effectively exclude herons without welfare costs and are increasingly required rather than lethal control.