Swans are birds found on every continent except Africa and Antarctica.

The swan's neck is long and slender. Its neck is the same as its body, or even longer. Their mouths are flat at the front and their tails are short and round. They are social animals and prefer to live in lakes and swamps. Swans feed mainly on aquatic plants, but also on snails and mollusks.

The swan is a winter migrant, migrating north from mid-March to mid-April and breeding from May to June. Swans build their nests on dry ground or in reeds on shallows. Their average life span is around 20 to 30 years, and the longest can exceed 50 years. The lifespan of swans is determined by their breed and how they are kept.

During the breeding season, swans mainly inhabit open lakes, ponds, swamps, slow-flowing rivers, and adjacent tundra marshes. In winter, it mainly lives in large lakes, reservoirs, and ponds with reeds and other aquatic plants. It also occurs in wet grasslands and flooded plains, swamps, beaches, and estuaries. Sometimes even near farmland.

Interestingly, swans are monogamous animals. It's their habits and their genes. There are three main reasons why swans choose monogamy.

First, as a typical migratory bird, swans spend the winter in a warm place every winter. Some swans travel up to 2,500 kilometers a year. A stable mate is very important to them. Because swans don't have a lot of time for constant courtship. Migrating swans, to ensure their survival will not easily abandon each other. The migration is a long way, and in addition to food shortages, they must always be on guard against enemy attacks. Together, swans can help each other better, which helps to complete the migration process safely.

Second, swans are very territorial. In their territory, they do not allow other swans to come near. This behavior leaves the swan alone in its territory with its mate. In a way, such behavior can make the swan couple's relationship more stable.

Third, when male and magnetic swans have babies, it takes a lot of time and experience to raise them. The whole family is highly valued. When a female swan lays her eggs and hatches her baby, the male swan stays with her baby to protect her baby from enemies.

So if one partner dies, does the other partner stop looking for a new partner? The answer is yes. If one of them dies, his partner cries into the sky and refuses to leave for a long time. The surviving swans do not seek a new mate, but raise their children and die alone.

Scientists have also carried out several experiments to test the swans' loyalty. They found that very few swans seek a new mate after the death of their partner. But they do so to survive their migration.

For most swans, monogamy is the norm.