The contrast in the pattern on the back is visible.

"Western Meadowlark has ... pale brown back, thin barring on wing coverts, 2 outer tail feathers mostly white. " (The Stokes Field Guide to the Birds of North America, p. 721)

"Eastern Meadowlark has ... dark warm brown back with reddish-brown tones ... broad dark barring on wing coverts; dark-centered upper tail coverts ...." (The Stokes Field Guide to the Birds of North America, p. 720)

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