Grebes: Order Podicipediformes

Grebes are medium-sized, foot-propelled diving birds with stocky bodies, slender necks, and small heads.

Like many highly adapted diving birds, grebes have difficulty taking off from the water; with rapidly beating wings, they must run across the surface before becoming airborne. The toes of grebes are lobed and the tarsi are laterally compressed, thereby offering little resistance when drawn forward through the water. The legs are located far back on the body, thus making it difficult for the birds to move on land but giving them a powerful forward thrust during dives. The claws on the toes are unusual in being flattened like fingernails.

The dense, satiny plumage of grebes is waterproofed by secretions from a tufted oil gland above the base of the tail. The tail feathers are reduced, so grebes look tailless, a feature that contributes to the stocky appearance of some species. Grebes eat their own feathers, which then trap fish bones in the stomach, holding the bones for prolonged digestion or regurgitation.

In most species, the bill is slender and pointed; but in some—for example, the Pied-billed Grebe of the New World—the bill is stouter, an adaptation to this bird's diet of hard-shelled crustaceans.

The sexes are similar in appearance; some species acquire distinct breeding plumages. Elaborate courtship displays include fancy dives and rises out of the water and prolonged rushes side-by-side. The young are clad in fine down at hatching. In most species, the down is handsomely striped in black and white; but the down is plain gray in the Western and Clark's grebes of North America. Most grebes build floating platforms of aquatic weeds on which they mate and lay their eggs. They carry their young on their back, even when diving.