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The African green pigeon (''Treron calvus'') is a species of bird in the family Columbidae, and one of 5 green pigeon species in the Afrotropics. As with others in their genus, they frequent tree canopies where their parrot-like climbing ability〔Gerhard Rösler: Die Wildtauben der Erde – Freileben, Haltung und Zucht, Verlag M. & H. Schaper, Alfeld-Hannover 1996, ISBN 3-7944-0184-0〕 enable them to reach fruit, but rarely also forage on the ground. The species has a wide range in Sub-Saharan Africa with around 17 accepted races. Adult birds have maroon shoulder patches (olive in immatures) and rufous undertail coverts. They reach a length of 25–28 cm. Their call is a series of flowing whistles, rendered as ‘thweeeloo, thweeeoo’. They inhabit riparian forest, woodland and savanna, where they associate with fruiting trees, especially wild fig (''Ficus'') species, including ''Ficus sycomorus'' and ''Ficus sur'', and in cities the ornamental Chinese banyan. They also take fruit of Saffrons (''Cassine'' spp.), Jacket plum (''Pappea capensis''), Buffalo thorn (''Ziziphus mucronata''), Water berry (''Syzygium cordatum'') and Jackalberry (''Diospyros mespiliformis''). They may also feed on exotic Loquats and Mulberries, or on carrion by occasion. They may occur and breed in high densities but are prone to regular local movements. Their range includes Angola, Benin, Botswana, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Republic of the Congo, Democratic Republic of the Congo, Ivory Coast, Equatorial Guinea, Ethiopia, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Kenya, Liberia, Malawi, Mali, Mauritania, Mozambique, Namibia, Niger, Nigeria, Rwanda, São Tomé and Príncipe, Senegal, Sierra Leone, South Africa, South Sudan, Swaziland, Tanzania, Togo, Uganda, Zambia and Zimbabwe. They nest in a tree fork that offers an adequate vantage point of their surrounds. The nest is a weak platform of sticks, collected by the male and arranged by the female.〔(Video of nesting behaviour, The Internet Bird Colletion )〕 Nesting may take place in any month of the year, though mostly in summer. 1-2 eggs are laid that hatch in 13–14 days. Chicks leave the nest at about 12 days. Image:African Green Pigeon (Treron calva) in fruit-bearing tree.jpg|''T. c. nudirostris'' feeding on wild figs, Gambia Image:Treron calvus glaucus, in vyeboom, f, Pretoria.jpg|''T. c. glaucus'' in a suburban fig tree, South Africa ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「African green pigeon」の詳細全文を読む スポンサード リンク
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