Two summers ago, a patient looking out his Belgian-hospital window spied in a tree an odd, abandoned magpie nest of plastic and wire. He had, by coincidence, just read a newspaper article about a ...

It’s the Mad Max dream of a bird’s nest: A menacing composite of metal, clay, twig and plastic. Spotted in a sugar maple tree in Antwerp, Belgium, the gnarly architecture brims with at least 1,500 ...

Picture a bird’s nest. Chances are, what comes to mind is a woven basket of twigs and plant fibers—you might not imagine a crown of metal spines. But that’s exactly how some crows and magpies in ...