The Queen owned swans, dolphins, whales, and sturgeons. Here's who inherits them now.

• King Charles III will inherit thousands of swans, dolphins, whales, and sturgeon belonging to the Crown.
• The reigning monarch was given symbolic ownership of these species in the 12th century to protect from poachers.

King Charles III is set to receive a vast inheritance from both the Crown and the private estate of his mother, Queen Elizabeth II, after she died Thursday — but some of the assets are a bit surprising.

While his inheritance includes items and entities long synonymous with the royal family — including much of the Queen's expansive jewel collection and the $750 million Duchy of Lancaster estate — it also includes stranger assets such as 32,000 swans and an unidentified number of dolphins, whales, and sturgeons, El País reported.

According to El País, the species became the symbolic property of the Crown in the 12th century in order to protect them from poachers. As part of their ownership, the monarch oversees the annual "Swan Upping" event, a census of the swan population on the River Thames.

In the past, the process — which involves weighing, measuring, and assessing the health of the birds — has been conducted by the Queen's Swan Marker, David Barber, according to the Royal Family's official website. The last Swan Upping the Queen attended was in 2009, Metro UK reported.

The event also became an educational opportunity for school children, who attend to learn more about the biology of swans and the species's place in the ecosystem, according to Metro UK.

Whales and dolphins officially came under the ownership of the Crown in 1324, thanks to an obscure statute that states they are recognized as "fishes royal." This was later expanded to include sturgeon and porpoises, and under the law, the monarch can claim any that are captured or washed ashore within 3 miles of UK shores, according to Time.

The animals are among the many assets that are part of the Crown — or items that belong to the institution and are not privately owned by the reigning monarch. Across all assets, both privately owned and those belonging to the Crown, El País estimates the Queen's total fortune at $16.2 billion.

According to The Sunday Times annual Rich List, the Queen's private net worth is $429 million, cumulatively amassed during her seven decades on the throne.