Displays territorial behaviors bordering on neurotic; exerts tireless effort protecting his feeder from other species. Missiles from above and violently spears the comparatively sluggish Black-headed Grosbeak who explodes in a shrieking burst of feather. I once saw this aggressor take a young Grosbeak to the dirt and stab the submissive victom repeatedly with his long, sharp beak ... Not my favorite feathered fellow.
I've considered a bb gun purchase and exacting vigilante justice to preserve the peace.

Lewis' Woodpecker

Melanerpes lewis  L 10¾" (27 cm)

Greenish-black head and back; gray collar and breast; dark red face, pinkish-red belly. Food source: Insects, mostly caught in air; also eats fruit, nuts. Stores acorns, which it first shells, in tree bark crevices. Range: Uncommon to fairly common in open woodlands of interior; rare on coast. Fall and winter movements unpredictable. Largely eliminated in coastal northwest; accidental in east.