Identification Keys and Tips
| Western Grebe | Clark's Grebe | |
| Aechmophorus occidentalis | Aechmophorus clarkii | |
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| Western and Clark's Grebe were only split into two distinct species in 1985, as prior to that, they were regarded as one species. The two species are very similar, especially in their winter plumage when their primary differentiating characteristic (facial pattern) becomes nearly identical (much less dark around the eye in winter-plumaged Western Grebes). Winter-plumaged birds are best distinguished by bill color. The photos of the two birds above are both summer-plumaged birds. Both were taken in very different light, but plumage, facial pattern, and bill differences are readily apparent. Note the Western Grebe is carrying young on its back, a common behavior in both species. Also note that intermediate birds are often seen. Extent of dark feathering around eye can vary widely in these birds, even in summer plumage, making identification even more difficult. Flank plumage is also often intermediate in hybrid birds. |
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| Facial Pattern (Summer Plumage): Black cap extends below and surrounds eye. | Facial Pattern (Summer Plumage): Black cap terminates above the eyes, with white surrounding the eye. | |
| Bill Color: Greenish-Yellow, often with two-tone look (darker at top and bottom of bill) | Bill Color: Bright yellow to orange | |
| Body Color: Flanks are generally dark | Body Color: Averages lighter on the flanks than Western, often with much white. | |
| South Dakota Status: Much more common in state of South Dakota than Clark's Grebe, especially in the eastern part of the state. | South Dakota Status: Rare in South Dakota, most frequently found in western part of the state. | |
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