bird-colonies birds breeding-place colonies color colors colour colours conservation contrast contrasting crowded dark estuarine-wetlands estuary estuary-waters fence fenced foliage food-supply forested-wetland habitat light low-lying melaleuca-rhaphiophylla migratory-birds nesting nesting-place nests nursery paperbark-trees paperbarks reserve ripples rippling rookeries rookery roosting roosting-place slow-flowing swamp-paperbark tidal trees vegetation water waterbird- habitat wetlands wildlife african balearica-pavonina banded beak bird black black-crested-crane black-crowned-crane black-head-patch captive crane crest crown display displayed displaying distinctive feathers forager golden-head-feathers gruidae gruiformes large long-legged long-necked omnivore omnivorous plumage spreading Sub-Saharan toes trained trees-roosting Ugandan-national-bird vertebrate white wings wingspan cloud Crows England english farm field Great Britain landscape meadow natural nature peaceful rural sheep sky South Downs summer Sussex tranquil