Langstone, Hampshire: Our smallest goose species doesn’t quite have the military precision of others, but there is still cohesion to their loose formations

A flock of geese winging across an estuary in V-formation is one of the most iconic spectacles of the season, but a rare sight in Langstone and Chichester harbours. In flight, our wintering dark-bellied brents lack the military precision displayed by other species, most notably pink‑footed and barnacle geese. Instead, they ribbon across the steely December sky in long, undulating lines or stretch out laterally in a broad front.

As I walk along the shore, 200 or so brents take flight, flushed from the coastal grazing by an off-lead dog. They momentarily jink and morph as one entity, reminiscent of a starling murmuration; then, as they wheel around, heading for the mudflats, the flock starts to elongate and splinter, irregular gaps appearing as sub-flocks form. At first glance, there’s no semblance of order, but as they pass overhead, I realise that some birds are arranging themselves into loose wedge-shaped formations.