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Grebes ( Podicipedidae ) By: Kristina Best Wetland Wildlife Management Eastern Kentucky University
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Taxonomy of Grebes Phylum: Chordata Class: Aves Order: Podicipediformes Family: Podicipedidae Genus: Podilymbus or Podiceps
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The History of Grebes The History of Grebes Grebes have been around for at least 80 million years. Many fossils have been found: Very successful species. Not closely related to any other birds.
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In General Diving Birds Legs set back on body Toes with three lobes for swimming Spend most of time in water and are very awkward on land Many have not been studied extensively Very diverse and interesting
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In General Distributed throughout the world Absent from the arctic, antarctic, and some islands in the ocean Grebes have one family (Podicipedidae), six genera, and 22 species They leave the water only to nest, walking very short distances upright like penguins.
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Grebe Toes Grebes Have three asymmetrically lobed toes that are thought to aid in swimming. Adds lift and increases energy efficiency. The toes being separate increases lift to drag ratio. (Johansson and Norberg 2000)
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Grebe Diving Feathers are dense and water proof On underside, feathers are at right angles to the skin. They stick straight out and then curl at the tip. By pressing feathers against the body, grebes can adjust their buoyancy. This allows them to swim in the water with only their heads above the water. They will often do this to hide instead of flying away.
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Pied-Billed Grebe Podilymbus podiceps 9-12 inches long Sexes similar Small grebe with a short, thick bill Brown plumage that is darker on back May or may not have a black ring around bill White coverts under the tail
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Pied Billed Grebe Lives in fresh water, but will go to salt water in the winter when ponds and lakes freeze Breeds in open water Seasonally monogamous Construct floating nests connected to vegitation 2 to 10 pale bluish or greenish eggs incubated by both parents 23 days until hatch
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Breeding Range
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Winter Range
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Pied-Billed Grebe Chicks will ride on parents back or cling to tail, although they can swim right after hatching Eat mostly aquatic invertebrates Sometimes eat fish, small reptiles, and amphibians
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Horned Grebe Podiceps nigricollis 11112-15 inches long SSSShort pointed bill SSSSexes similar SSSShort, thin, black bill with pale tip BBBBreeding: Head black with gold strip going from back of eye to back of head. Reddish neck, dark back, and white belly. WWWWinter: Black cap, hind-neck, and back. White face, fore- neck, and belly.
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Horned Grebe Breeds on marshes and lakes Winters on saltwater and lakes that do not freeze 4-7 bluish white eggs Incubation 22-25 days 45-60 days till fledge Young can swim after hatching Ride on parents back
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Breeding Range
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Winter Range
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Horned Grebe Eat mainly fish and aquatic invertebrates Swallow own feathers which lodge in stomach and prevent fish bones from interring intestines Rarely seen at night. Once on wintering grounds they seldom fly Migrate at night
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Eared Grebe Podiceps nigricollis 12 inches long with a 23 inch wingspan Short, thin, black bill with no pale area Sexes similar Breeding: Black head with a golden ray of feathers behind eye. Black neck and back with reddish sides. Winter: Gray/white neck and chin. Dark body with whitish sides.
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Breeding Range
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Winter Range
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Red-necked Grebe (Podiceps grisegena) 18-20 inches has red neck, black cap, whitish cheeks, and long, pointed yellowish bill. In winter, grey with paler cheeks and bill
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Breeding Range
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Winter Range
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Western Grebe 18 inches long with a 40 inch wing span Long neck and long, yellow-green bill Black crown, nape, and dark body White neck and belly
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Other Grebes
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Key to the Grebes Overall size? = Robin-sized Bill shape? = short & thick.... Pied-billed Grebe = thin bill Eye color? = yellow.... Least Grebe = red Season? = summer Golden tuft? = horns like an expanding eyebrow.... Horned Grebe = ears fanning out behind eye.... Eared Grebe = winter Face? = black cap above eye, white face below eye.... Horned Grebe = black face with white U-shaped crescent along lower edge... Eared Grebe = Mallard-sized Neck color? = red-fronted in summer or mottled gray in winter.... Red-necked Grebe = black & white, sharply defined edges Eye background? = white around eye.... Clark's Grebe = black around eye.... Western Grebe Pied-billed GrebeHorned GrebeEared GrebeRed-necked GrebeClark's GrebeWestern GrebePied-billed GrebeHorned GrebeEared GrebeRed-necked GrebeClark's GrebeWestern Grebe
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Management Practices Control sedimentation, pollution, and water levels Develop or maintain wetlands Don’t let livestock in or on bank of stream or wetland Control predators: Wild dogs Restrict human disturbance during migration, breeding, and nesting Maintain good vegetation for breeding
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Avoid installation of channels and dams Avoid dredging Control the use of herbicide, pesticide, and insecticide
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Questions?
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