The above photo is taken from "The Island" looking at an island in the estuary, the day before yesterday. A quiet, pleasant afternoon... 
There were birds about -- it is a Ramsar Wetlands Area and an IBA (important bird area). We saw cormorants, duck, terns, gulls, pelicans, egrets, herons, darters, Black Swans, a Whistling Kite (which you can see against the white of the puffy cloud over the trees...)


More and more of them arriving by the minute, all heading in the same direction...
To this area above, where pelicans and cormorants were diving like maniacs and other birds gathered to glean the remains of a fish feast.
Until, below, the pelicans and other birds were so thick on the surface, we couldn't see the water.
Interestingly, the cormorants were behaving in a remarkable way when they were on the surface, thrashing the surface with their wings, ploughing and churning up the water. The only reason we could think of was that they were actually trying to herd the fish or confuse them in a way that benefited other birds.
The schooling fish vanished, the birds disappeared, and the rainbow arced into the sky...
I love my island.