Clark's Grebe (Aechmophorus clarkii) is a large (55-75 cm) waterbird that has a black cap and back, white neck and underside, and is distinguishable from the western grebe (Aechmophorus occidentalis) by their white face and bright yellow bill. They breed in the western U.S., Mexico, and southwestern Canada. They inhabit marshes, lakes, and bays where they feed on fish and aquatic invertebrates.