Sculptures provide homes for tiny ocean residents.

The island of Kinmen, Taiwan—where oyster cultivation is a long-standing tradition—was the final flashpoint of the Chinese Civil War in 1949. More recently, Finnish environmental artist and architect Marco Casagrande noticed that rusted steel anti-landing poles still standing in the waters around the island are covered in oysters—and that filled him with hope. “Even the war tectonics can be taken over by nature and transformed into life-providing systems,” he says.

When creating Oystermen (2013), part of the Floating Islands art festival project at the Shanghai Biennale, Casagrande was further inspired by the long reflections of oyster farmers’ legs in the water. The permanent installation consists of four towering stainless steel sentinels, who stand six meters tall along an ocean road at low tide.

When the tide rises, the trail connecting Greater Kinmen to a smaller island disappears under the ocean’s watery embrace, as does half of each sculpture. At high tide the Oystermen—whose conical hats are covered in solar panels that power LEDs underneath at night—appear to stand on the water’s surface. Over time, oysters will envelop their submerged legs, creating an artificial reef.