While spending time on the Tempe Town Lake Pedestrian Bridge ogling at the Red-necked Grebe, I started to notice small variations among the Western Grebes. The grebe on the right in the above photo seems to have white lores, and grey plumage above the eyes, while the grebe on the left does not. The bill is only slightly yellower than the Western's, not strikingly so. Is the one on the right a Clark's Grebe?
Try as he/she might, the Clark's couldn't interest the Western in gathering nesting material.
Above are 2 Western Grebes with their darker bills, black lores, and dark plumage just below the eye.
From left to right - 2 Western Grebes, a possible Clark's Grebe, and the Red-necked Grebe.
The poor Red-necked Grebe kept getting chased away by the trio.