As I mentioned Starlings in post 135, I thought that it might be worth including this video showing the behaviour of a large flock of the species (a murmuration) prior to roosting for the night beneath Aberystwyth pier on the west coast of Wales.
The resident population of the bird has declined dramatically in recent years to the extent that it is now on the Red List of endangered species and winter numbers are boosted by flocks from Scandinavia and Central Europe.
The flight patterns they make are something of a spectacle. Worth a few minutes of your time.
There's more here:
Aberystwyth Starlings