Moa (New Zealand) - extinct, but shrouded in mysteryr. 

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Ivory-billed Woodpecker (USA) - thought to be extinct, but sightings reported

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Whooping Crane (USA) - one of the rarest birds in the world

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Mauritius Pink Pigeon (Mauritius) - rare and elusive

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Spiny Babbler (Asia) - rare and poorly understood

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Slender-billed Vulture (India and Pakistan) - critically endangered and mysterious

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Jerdon's Courser (India) - rare and poorly understood

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Hooded Mountain-gem (Central America) - rare and elusive

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