Red squirrels in Britain and Ireland face local extinction from competition with and disease carried by introduced grey squirrels, creating welfare challenges for conservation programs.
Red squirrels in areas without grey squirrel control face prolonged die-offs from squirrelpox. The disease causes skin lesions, blindness, and death over days to weeks. Conservation programs that trap and kill grey squirrels cause welfare harm to the controlled species to benefit the protected species. Translocation of red squirrels involves capture stress. These competing welfare considerations are inherent in managing introduced species impacts. The welfare of both species deserves consideration in management decisions.