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