Wheeling birds often look portentous, like they know something we don't. They do, of course. There must be plenty they know and sense that we can't begin to imagine, some of which leads them to turn in strange arcs through the sky, to scatter then reassemble their flocks.

Today I was walking into town, past the old converted mill building on the slimy banks of the Colne, luxury apartments that have been there for as long as I can remember. A man stood outside with a cigarette and a steaming mug of tea, watching a large tumble of gulls reconfigure themselves endlessly on the horizon. I paused to watch them, then watched him watching them, until he turned to look at me, and I walked on. We had our patterns, and the birds had theirs.