Bird of the Month: Western, Clark’s grebes

audubon-logo-wood-duck-square-medium-300x300By DeeDee DeLorenzo

Western and Clark’s grebes are found throughout Arizona and are common breeders in the marshes along the Colorado River. Both species are about the size of a loon and have contrasting black and white plumage and relatively long, slightly curved necks. Until 1985, they were thought to be color phases of the same species — namely, the Western Grebe.

There are several ways to identify each species. A breeding Western Grebe’s black cap extends below the eye, while the Clark’s Grebe’s cap stops above the eye. Another way to distinguish the two birds is by bill color. The Western’s bill is a drab greenish-yellow; the bill of the Clark’s is orange-yellow to bright yellow.

A less obvious way to tell these two grebe species apart is by their overall body plumage. The back and sides of a Western Grebe are dark with little or no white mottling. The Clark’s Grebe will show some white on the sides and the back tends to be lighter.

The Western makes a creaking, two-note call and sounds like a gate slowly opening then shutting: “ker-kreek.” The Clark’s Grebe makes a single syllable call: “k’rrree.” The gate opens, but doesn’t close.

Behaviorally, the Western and Clark’s grebes have a lot in common. During the winter, they share the same lakes and ponds. Here they can be seen gliding on the water with their heads slightly submerged or diving as they search of fish and crustaceans.

During the breeding season, their courtship displays are identical. The pair will rise from the water simultaneously and run on top like a pair of synchronized Olympic competitors. These rituals begin in February and continue until mid-May.

Nest building begins in March and is shared by both sexes. A typical clutch is comprised of two to five eggs and is incubated by both parents for about 23 days. When the chicks hatch they spend six to eight weeks with their parents who share the responsibilities of “back-brooding” and feeding their young

 

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Visit Prescott Audubon Society at PrescottAudubon.Org. Contact them at Contact@PrescottAudubon.Org.

DeeDee DeLorenzo resides in Bullhead City and is a retired elementary school teacher, Prescott Audubon Society board member, and dedicated supporter of the Friends of The Bill Williams River and Havasu Wildlife Refuge.

 

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