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Canon 6D, Canon EF 100-400L ƒ4.5-5.6 IS USM, at 400mm, ISO800, 1/320, ƒ/5.6

The nuthatches constitute a genus, Sitta, of small passerine birds belonging to the family Sittidae. Characterised by large heads, short tails, and powerful bills and feet, nuthatches advertise their territory using loud, simple songs. Wikipedia