Giant Things of Oaks, PA
8 years ago
Bill Schmoker's Nature & Birding Blog

Breeding Eared Grebes (above, Colorado, April) have all black necks and wispy yellow plumes that radiate out from the eye area. Note how dark feathers can be seen through the plumes, and the sharp crest atop the head. Breeding Horned Grebes (below, North Dakota, June) have a solid yellow swipe of feathers going back from the eye, a flatter head, a rufous neck, and a little white tip to the bill. No problemo, you say?
The problemo is that these birds now show a very similar pallate of white, gray, and black in about all the same places when in non-breeding (basic) plumage. Structure can still be helpful, as Eared Grebes (below, Colorado, November) typically show a more domed head than Horned. Note also the blurry-looking border between the dark cap and the light neck. Also note that darkness extends behind and below the eye (feathers known as auriculars.) Eared Grebes are often willing to forage near the edge of lakes, particularly along rocky shores. They can also be seen far from shore, though.
In contrast, winter Horned Grebes (below, Colorado, November) have a more sharply defined dark cap and the eye is right at the edge of the darkness, with white below and behind in the auriculars. Their heads almost always look flatter than Eared Grebes', and most of the time there is a white spot on the lores (feathers in front of the eyes.) If you get a good enough look, you will see that the white bill tip is retained in the winter. To me they look somewhat like dwarf Western Grebes in their basic plumage. It occurs to me like seeing Horned Grebes near shore is much rarer than with Eared Grebes.

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