Recalibrating risk: implications of squirrelpox virus for successful red squirrel translocations within mainland UK

Introduced grey squirrels (Sciurus carolinensis) cause native red squirrel (Sciurus vulgaris) decline via resource competition (Wauters, Gurnell, Martinoli, & Tosi, 2002) and carry squirrelpox virus (SQPV). Infection is sporadically transmitted to red squirrels and spreads within the population—precipitating disease. Sainsbury et al. (2020) assert that UK mainland red squirrel reintroductions cannot be justified in light of international guidance and that translocations will fail because of SQPV. They suggest animal suffering will result because grey squirrel control cannot be sufficient to prevent epidemic disease amongst sympatric red squirrels.