A pair of common loons with eyes locked on each other in a behavior known as the circle dance on Pawtuckaway Lake in Nottingham. This behavior involves two rival loons swimming circles around each other as a test of fitness. Telegraph photo by CHRISTOPHER ROBERSON

A common loon stretching its wings on Pawtuckaway Lake in Nottingham. A loon’s wingspan can reach up to five feet. They are also capable of flying at up to 75 miles per hour. Telegraph photo by CHRISTOPHER ROBERSON