Ladder-backed Woodpecker
Dryobates scalaris
The ladder-backed woodpecker is a small woodpecker about 16.5 to 19 cm (6½ to 7½ inches) in length. It is primarily colored black and white, with a barred pattern on its back and wings resembling the rungs of a ladder. Its rump is speckled with black, as are its cream-colored underparts on the breast and flanks. Southern populations have duskier buff breasts and distinctly smaller bills. Adult males have a red crown patch that is smaller in immatures and lacking in adult females.
ID text from Wikipedia, CC BY-SA 4.0
Nuttall's Woodpecker
Dryobates nuttallii
Nuttall's woodpecker has striped black and white patterned wings and tail feathers with white. Its undercarriage is a primarily white coat with a few spotted black regions. It has a black forehead with white streaks on the sides and an unbarred black region at the top of the back. Adult males have a distinguishable red crown which females do not. However, this physical feature is present in the juvenile of both sexes. Juvenile birds look nearly identical to adults, excluding that juveniles typically have some white color in the form of streaks on their heads. Voice: Vocalizations performed by Nuttall's woodpecker are considered to be not of any harmonic. Some vocalizations have been described: Call note: used between mated pairs to communicate their location to each other. Double call: same function as call note can but also be used as a low threat alarm call.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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