American Pipit
Anthus rubescens
  "Grayish brown and faintly
  streaked above, this six-inch pipit has buffy underparts streaked
  with brown ... the slim profile, and the slender, warblerlike
  beak serve to distinguish the pipit from several sparrows of
  similar size and color."
  "The back grayish with faint
  or no streaking ... breast and flanks buffy, heavily streaked
  to unstreaked ..." (The Stokes Field Guide to the Birds
  of North America, p.585)
  The back contrasts with the "Strongly streaked black and
  whitish on back" (The Stokes Field Guide to the Birds
  of North America, p.584) of Sprague's Pipit.
  The tail feathers.
  
    
      Photo taken with a Nikon D90 using
      a Nikon 400mm, f/5.6.
      December 30, 2011.