Look away if you’re squeamish. The chalkstreams are incredibly beautiful, but, scratch the surface, and it’s a pretty tough place to survive. Otters eat fish. Mink eat water voles. Owls eat field mice. Fish eat other fish. A heron just loves a frog and kingfishers can dip for a minnow a minute for hours on end. Swans are famously aggressive and tales of human broken arms abound, however, this account shows a far more chilling side to their nature.

Midway through the afternoon, a male swan came charging upstream, followed by its partner. Looking upstream, the fishermen could see another swan. The intruder kept feeding until the incumbent male got within 10 yards, then turned around and charged into it, rather like two stags.

Ultimately, the incumbent male was stronger and was quickly on top of the intruder, gripping its neck with his beak. He then started to beat the body of the intruder with his feet while repeatedly pushing its head under water. Soon, the intruder seemed to give up. The incumbent kept his grip on the other’s neck and held its head under water even when it was clearly dead, as its mate joined in. All three drifted downstream, with the two incumbents continuing to attack the dead swan.

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