Grey squirrels introduced from North America have displaced native red squirrels across Britain through competition and disease, creating a welfare dilemma in native species conservation.
Grey squirrel management creates a genuine welfare dilemma. Grey squirrels are highly sentient mammals capable of suffering, yet their presence causes population-level harm to red squirrels through disease transmission. Lethal control through cage trapping and killing (typically by CO2 or shooting) is the currently standard approach and is effective when coordinated across landscapes. Methods including spring traps and shooting cause varying welfare outcomes depending on placement and operator skill. The grey squirrel contraceptive bait in development would be a significant advance, allowing population reduction without lethal control. Red squirrels themselves suffer significantly from squirrelpox, making prevention of transmission a welfare priority for the species being protected.