Clark's Grebe (Aechmophorus clarkii) is a North American species in the grebe family. Until the 1980s, it was thought to be a pale morph of the Western Grebe, which it resembles in size, range, and behavior. Intermediates between the two species are known.
The "Clark" of its common name—and its specific epithet "clarkii"—honor John Henry Clark, a 19th-century American surveyor who was also a naturalist and collector.The genus name Aechmophorus comes from the Ancient Greek words "aichme", meaning spear, and "phoros", meaning someone who bears things around; it refers to the bird's long, daggerlike beak.
This species nests on large inland lakes in western North America and migrates to the Pacific coast in winter. It maintains local populations year-round in California, Nevada, Arizona-(the Lower Colorado River Valley), and central Mexico. It feeds by diving for carp, herring, mollusks, crabs, and salamanders.
A white-faced version of the Western Grebe, the Clark's Grebe formerly was thought to be the same species. Differences in face and bill color keep the two grebes from interbreeding.
Adult Description
Medium-sized waterbird.
Black back and cap.
White face.
White neck and underside.
Long neck.
Long, thin bill.
Habitat
Clark's grebes have a wide range but are relatively uncommon. They can be found on large, open freshwater or saltwater marshes, reservoirs and lakes throughout the west, with summer populations extending as far north as the western halves of the Dakotas through Montana, southern Idaho, Nevada, Colorado and Utah. In winter, the birds migrate to the Pacific Coast from southern Oregon to Baja California, with more isolated winter populations found in western Texas and eastern New Mexico. Year round populations can be found in central California and Mexico, as well as along the California-Arizona border.
Reproduction
These are monogamous birds that mate after an elaborate courtship display that includes "dancing" across the water and sharing reeds. A mated pair will build a floating nest and both parents will incubate the 2-6 eggs for 23-24 days. The precocial hatchlings will climb onto their parents' backs within minutes of birth, and will remain under both parents' care for 63-75 days until their first flight. Because of the long growth period, Clark's grebes raise only a single brood each year.
Length
21.7–29.5 in
55–75 cm
Wingspan
31.9–32.3 in
81–82 cm
Weight
25.3–59.4 oz
718–1685 g
Other Names
Le Grèbe de Clark, Grèbe élégant, Grèbe à face blanche (French)
Achichilique, Acitli (Spanish)
Behaviour
The Clark's grebe is a superior swimmer and diver but can be slow and awkward on land. As opportunistic feeders they will sample many different foods but feed primarily on fish. Young grebes ride on their parents' backs and stay in position even during feeding dives. When threatened, Clark's grebes are much more likely to dive than to take flight.
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