Swans choose their mate at a young age, when they are only a couple of years old. There is a complex courtship display when swans face each other, and dip and turn their heads or spread and raise their wings. They also "kiss bills," which forms the famous heart shape with their necks. Many swans are monogamous and mate for life, but some pairs are not. If the swan couple has trouble reproducing, they "divorce" and find new partners.