On a pleasantly warm summer’s day, a steady procession of traffic eases over the stone bridge carrying the A44 across the river Severn at Worcester and out past the county cricket ground. In the shadows of the masonry arches, scarcely noticed, a pair of common terns engage in aerial ballet – wheeling, turning, stalling momentarily before plunging, fully submerged, into water the colour of tea with too little milk.
Whatever it is they are catching, momentarily attracts the attention of a few of the much larger birds they have for company; most of them simply continue to drift with the slow current. In any event, none of the gulls – herring, lesser black-backed, even the nifty and mobile black-headed variety – is anywhere near quick enough to effect a mugging before the food is swallowed whole and on the wing. The terns, for their part, seem wholly indifferent to the presence and interest of their larger neighbours; they are busy, and hungry.