Horned grebes ( Podiceps auritus) closely resemble eared grebes (Podiceps nigricollis) – another “pair” of look-alike birds that are so difficult to identify.
Recently I observed a solitary horned grebe on the Tule River (Shasta County CA). Since the breeding plumage of both male and female horned grebes look the same, I could not tell the sex of this lone duck. No other grebe was in sight and this grebe appeared perfectly content to be alone. For about fifteen minutes I watched as it dove and resurfaced, all the while slowly drifting downstream.
Horned grebes are excellent swimmers and can dive deeply. Because their legs are placed far back on their bodies, this small duck finds walking difficult and awkward and therefore spends almost all of its life on the water. Aquatic insects, fish, crayfish and other small aquatic animals comprise the horned grebe’s diet.
The horned grebe has black or grey and white eclipse (not breeding) plumage which becomes more dramatic and colorful during the breeding season. In the spring and summer, a horned grebe displays a black head and back with a cinnamon neck, breast and flanks. The eyes are scarlet and connected to the bill by a thin red line. Puffy buff, yellow or gold tufts, “horns”, form behind the eyes. The black bill is tipped in white. There are many subtle structural cues for separating the eared and horned grebes, such as size, crown flatness, puffiness of tail, narowness of bill, forehead slope to name a few. But to me these structural details are so variable and subjective, especially when the two species are not side by side for comparison, that I always search for more definitive means of separation. The white on the tip of the bill and the red line from the eye to the bill point to a horned grebe rather than an eared grebe. Additionally the postocular plumes of an eared grebe are more fanned while the horned grebe’s do look more like a horn.
After wintering along the coasts of North America and in larger bodies of water, often saltwater, the horned grebe migrates inland to small and medium-sized freshwater ponds and marshes to breed. Both males and females build the floating reed nest anchored to plants along the edge of the water. The nest is always wet and the eggs are never dry. A chalky coating keeps moisture out of the egg. The heat generated by the rotting plant material from which the nest is constructed helps keep the eggs warm.
Hopefully this lone horned grebe eventually found another grebe to appreciate its colorful plumage.