Red squirrels survive in mainland UK strongholds and island refugia after displacement by grey squirrels and squirrelpox disease, with active management sustaining welfare.
Squirrelpox infection causes severe suffering including swelling, lethargy, and scab formation before death within two weeks. Grey squirrel control through lethal means raises welfare concerns for the grey squirrels removed. Vaccination programmes for red squirrels remain experimental. Island refugia provide disease-free populations at welfare cost of geographic isolation.