An elegant creature for a majestic setting. These all-white birds with yellow-and-black bills, gliding on the mirror of Lake Kussharo in Japan, are the Eurasian whooper swans, also known as the common swan. Named for their loud 'whooping' call, these beauties, with a wingspan between 2 to 3 metres, are one of the world's heaviest birds that can fly. While whooper swans are Finland's national bird, they only spend their breeding season there. Those swans, as well as others in various northern areas migrate to warmer, often coastal areas when cold weather sets in. All that travel doesn't ruin their relationships—these waterfowl form strong, monogamous pairs that can last for life.