The "bird at crest of head" iconography has also been described by Alan Day, site 33GU218 located on his property, Day's Knob, in Guernsey County, Ohio. The bird's posterior and the human's nose are the same element in the stone. The bird and the elephant also share the same eye. Please note the continuation of the carving lines to create a feature below the beak highlighted in white, beyond the point where they intersect, showing two, confident, stroke actions by the artist to execute the pointy feature.
A possible interpretation here of the shared human nose and bird posterior, as indicated by the arrow in the photo, is "the human breath of life becomes bird waste" as a symbolic representation of funerary practices in which birds are utilized to dispose of human remains.
Jim May's Facebook album link titled "Small faces," and showing some of the small carved faces Jim identified on additional finds at Washougal, Washington.