The Eurasian collared dove is a dove species native to Europe and Asia; it was introduced to Japan, North America and islands in the Caribbean. They are considered sly and aggressive competitors, engaging in fierce fights with rivals, striking with beak and wings, pulling feathers, and even jumping on a rival's back. - Wikipedia

They exhibit aggressive "bully' behavior as soon as they arrive at my feeders. Immediately, they will chase off Mourning Doves first, and then any and all competitor species.

See any other birds in this image? No? That's because they shooed them away. Eventually, the other species return to feed by staying clear of the Dove's aggression.

The Mourning Dove on the other hand is very calm and peaceful with its feathered friends with an attitude of " All are welcome, plenty to go around for everyone".

The Hawks that hunt here often target the doves of both species. Bigger meal for the effort. I have seen feather piles in my yard after an attack.

Canon T3i with 70-200 Canon Zoom lens @ 200mm, handheld.

Cropped, contrast enhanced to reduce kitchen window glare/reflections.