It initially appears as if it's petting the deer, but the bird's actions have a purpose: they are gathering hair from the muntjac to use in building a nest. It's a common behavior for magpies and ...

With their large size, bold pied plumage, and fondness for open areas, black-billed magpies are easily seen. They hop and walk on the ground with a swaggering and confident gait. Monotypic.