“Sat like a Cormorant,” Milton wrote of Satan in Paradise Lost, “devising death to them who lived.” I recall these lines now because the fisherman I met at this lovely country park was of similar mind. “If that’s a gun you’ve got,” he said, referring to my camera and monopod, “can you shoot them; they steal all my fish.” “Your fish?” I asked. Yet there was probably one point on which we agreed. Cormorants are better at catching fish than he is. The reservoir here is narrow but deep-watered and bound on both shores by steep-sided beech woods, which immerse the western half in a well of late afternoon winter shadow. Twelve cormorants, some of the southern race Phalacrocorax carbo sinensis, descended on to its silky green-black surface. They worked as a pack, sending out patterns of sparkling spray and white-edged ripples across the water’s quaking plane. One after the other, birds made quick-fire dives. Each was a perfect lesson in instant line and ancient purpose. The head and neck were recurved but arrowed down in the exact split second that the heavy body was raised clear of the water to drag thick paddle-feet hard behind. It made of each bird an exquisite ellipse of sinew and muscle from beak to tail. Down they went. The submerged snake-lines were marked by slight swellings in the surface sheen. No dive was less than 30 seconds. Then up they thrust again, splitting the plate of closed water like a gutting knife. I’ve seen them hunt like this on Lake Prespa in Greece, where 300 sinensis cormorants will encircle a fishing party of pelicans. I’ve also watched them do it in Portugal, where herons and egrets become so excited by the frenzy of fish-catching that they plunge in themselves and surround the melee in short, awkward failed sorties. Then a signal seemed to go out. The fish were done. Twelve birds lumbered up, and by the time I’d sorted exposure, adjusted ISO and shutter speed, got focus and pulled the monopod to the correct length, there was a beautiful vision of silvery fractal patterns spreading from so many black feet as their owners flew away.