Species Of Grebes, Conservation Of Grebes, Status Of North American Grebes
Grebes are aquatic birds that make up the family Podicipedidae. This is the only family in the order Podicipitiformes, a rather unique group of birds that is not
closely related to other living orders, and has a fossil lineage extending back 70 million years. The 20 species of grebes range in size from the least grebe (Podiceps dominicus), with a body length of 9.9 in (25 cm) and weight of 4 oz (115 g), to the great crested grebe (Podiceps cristatus), 18.9 in (48 cm) long and weighing 3.1 lbs (1.4 kg). The wintertime color of grebes is brown, grey, or black on top and white below, but during the breeding season most species develop a rather colorful plumage, especially around the head and neck.
Grebes are well adapted to swimming, with feet placed far back on the body, and paddle-like, lobed toes that provide a greater surface area for propulsion and a very short tail. The dense plumage of these birds provides waterproofing and grebes are strong, direct flyers. However, once they are settled in a particular place for breeding or feeding, grebes tend not to fly much.
Grebes breed on freshwater lakes and marshes on all of the continents except Antarctica. Some species winter in coastal marine waters, or on large lakes. Grebes have a noisy courtship behavior, often accompanied by a spectacular display. For example, courting western grebes (Aechmophorus occidentalis) run in tandem over the water surface, each bird striking a symmetric, ritualized pose known as the penguin dance.
The nests of most grebes are made of anchored, piled-up mounds of vegetation in shallow water. The young chicks often ride on the back of their parents, where they are brooded. The prey of these birds includes fish and aquatic invertebrates.
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