Whooper swans spending winter in the coastal city of Rongcheng in Weihai, Shandong province have been seen warming up for their journey to Siberia as the weather gets warm, according to Rongcheng Swan National Nature Reserve.

Some whooper swans in the city have shown signs that they are preparing to set out on their journeys, and most will start migrations in early March, said the reserve.

To provide enough food for the swans, the reserve has been distributing corn at places where the swans are living.

With its geographic location and wetland habitats, Rongcheng is important to migratory waterbirds, with over 20,000 estimated to stay at the site annually, according to the reserve. The whooper swans migrate annually from places including Siberia and stay for around five months at the bay in Rongcheng, making it one of the largest wintering grounds of whooper swans in the world.