sun grebe, common name for a tropical, mainly aquatic bird of the family Heliornithidae. Sun grebes, also called finfoots, are remarkable for their colorful, puffy-toed, webbed feet, which may serve as lures for fish and other aquatic animals. They are good divers and hunt, either swimming partially submerged or from low perches. Their diet consists mainly of small aquatic animals, but they are also known to eat some plant matter. They have elongate bodies, about 12 to 20 in. (30.5-51 cm) long, and necks with long and pointed, grebelike bills. However, they are not related to the true grebe. Shy and solitary creatures, sun grebes are found singly or in pairs, typically in the vicinity of densely wooded pools and streams, and little is known of their habits. Once widely distributed, they are now limited to three species. The largest of these is the Asian sun grebe (Heliopais personata) measuring up to 20 in. (51 cm) in length, and found from Bengal to Malaya and Sumatra. Its body is olive-brown above, with a black head and throat, a yellow bill, and bright green legs with white stripes. At 16 in. (41 cm), the African finfoot (Podica senegalis) is dark brown with black and white spots above, a white belly, and bright red feet and legs. It is thought to be more of a climber than the other species. Only a third to a quarter as bulky as the Asian sun grebe and measuring less than 12 in. (30 cm) in length is the American sun grebe (Heliornis fulica) of South and Central America. Its plumage is colored similarly to that of the Asian sun grebe, but it is scarlet-billed with yellow, black-striped legs. All three species are marked by a white band running from eye to neck. Sun grebes build their nests from grass and reed, on platforms away from water. The female lays from two to five white, red-and-buff streaked eggs per clutch. Sun grebes are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Gruiformes, family Heliornithidae.

grebe, common name for swimming birds found on or near quiet waters in most parts of the world. Grebes resemble the loon and the duck; they have short wings, vestigial tails, and long, individually webbed toes on feet that are set far back on a short, stubby body. They float lower in the water than do ducks, and at the approach of danger they sink progressively lower and then submerge, a practice which has given them the name helldiver.

They are poor fliers and awkward on land; their loosely constructed nests are either hidden in the rushes and weeds at the water's edge or placed on floating vegetation fastened to growing plants. Many grebes cover their eggs with refuse when they leave the nest, and some carry the young on their backs. They have complex courtship rituals, including dancing in pairs on the water. They eat crustaceans, fish, and aquatic insects and plants; unique among birds is their unexplained habit of swallowing feathers. Grebes were formerly hunted for their silky breast feathers.

The best-known representative in the Western Hemisphere is the pied-billed grebe, Podilymbus podiceps, locally called dabchick, water witch, and didapper. Other grebes are the western and Holboell's grebes of North America and the eared and horned grebes of North America, Europe, Asia, and Africa. There is a flightless species in South America.

Although grebes have been considered to be related to the loon, DNA testing suggests that they may be most closely related to the flamingo. Grebes are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Podicipediformes, family Podicipedidae.

Any of about 18 species of diving birds (family Podicipedidae) found in most tropical and temperate areas and often in subarctic regions. Most species can fly, and some are migratory. Grebes have a pointed bill, short narrow wings, and a vestigial tail. The position of their legs, set at the rear of the body, makes walking awkward. They feed chiefly on fish or invertebrates. Courting or rival males perform elaborate aquatic dances in pairs. Species range from about 8 to 29 in. (21–73 cm) long.

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