Sparrowhawk, Accipiter nisus.
Sparrowhawks are small birds of prey adapted for hunting birds in confined spaces like dense woodland and gardens. Females and young birds have brown back and wings, and brown bars underneath. Males have bluish-grey back and wings. Females, being larger than males, as with all birds of prey, can catch birds up to pigeon size. Some sparrowhawks catch bats.
Photo: © Kevin B Agar