I am just wondering that most birds are socially inclined before the night settles. They like to do some sort of a 'choral' type of chattering with each other. In fact a small breed of Passer montanus are now performing this typical 'social- choral function' in the tall young Sandoricum koetjape near the road trying to conquer this tree as their own as early settlers: they have been doing this for the past two or three weeks. They usually do this at about five or past five in the afternoon. As to my observations in a specific place in Africa, the birds blanketed the skies during twilight- usually in social groups as one being of the same species but there are times that some birds flew by themselves and one alighted in a huge tree, Tamarindus indicus by itself. Whether alone, in small or huge group, they flew together as one wide band spanning and hurrying up as if there is someone chasing after them to go to their roosting sites. This could be a different type of socialization with a broad perspective consisting of multispecies ones. Besides the "choral- social" chatter, starlings when they did their migratory flights, especially at dusk, showed their best performance (is it?). In this respect, I am just as curious why they behave this way before the night settles. There is more bonding, I suppose. I would like to do research on this and I don't want a duplication.
Here is the link to the starling birds doing wonderful migratory movements at dusk- http://www.jpost.com/Not-Just-News/AMAZING-VIDEO-A-flock-of-starlings-form-spectacular-flyover-in-Israels-sky-389818