Red squirrels face extinction across most of Britain due to competition and squirrelpox disease introduced by grey squirrels, raising complex welfare and conservation questions.
Grey squirrel management through lethal control raises welfare questions about the killing of individual animals that are not themselves at fault for their invasive status. However, without management, red squirrels face local extinction and the welfare costs of squirrelpox disease are severe - affected red squirrels suffer skin lesions, eye swelling, and death. The welfare of individual grey squirrels must be weighed against population-level welfare of red squirrels in conservation decision-making.