Grey squirrels are intensively managed across the UK to protect native red squirrels and woodland birds, with welfare implications for the millions of individuals killed annually.
Lethal trapping causes death by drowning, shooting, or crushing depending on trap type. Spring trapping of lactating females leaves dependent juveniles in dreys to starve. Cage traps that are not checked frequently cause prolonged suffering. Grey squirrels, despite being invasive, are sentient animals capable of suffering. Immunocontraception being developed would reduce the need for mass lethal control.