A pair of crested ibises from China arrive at Japan's Narita Airport, Oct. 17, 2018. (Xinhua/Hua Yi)

TOKYO, Oct. 17 (Xinhua) -- A pair of crested ibises from China arrived in Japan on Wednesday as a symbol of friendship between the two countries.

The pair of rare birds arrived in Japan's Narita Airport Wednesday afternoon, and were transferred to the Sado Japanese Crested Ibis Conservation Center in Niigata prefecture around evening.

The donation was made by China for the first time since 2007, and a signing ceremony of the handover document was held Wednesday.

Li Chunliang, deputy director of China's National Forestry and Grassland Administration, said at the ceremony that the arrival of the pair of crested ibises is an important action for protection of the rare birds as well as an embodiment of cooperation between China and Japan in wild animal protection.

The pair of crested ibises, named Lou Lou and Guan Guan, respectively, will bring not only rich genetic diversity but also Chinese people's friendship to Japan, he said.

A crested ibis from China receives physical examination at the Sado Japanese Crested Ibis Conservation Center in Niigata Prefecture, Japan, Oct. 17, 2018. (Xinhua/Ma Caoran)

Takaaki Katsumata, Parliamentary Vice-Minister of the Environment in Japan, said that the crested ibises are a symbol of the friendship between China and Japan, and their arrival will help the protection of Japanese crested ibises and promote communication and cooperation between China and Japan in this area.

A crested ibis is an iconic bird deeply rooted in Japanese history and culture. However, the number of crested ibises in Japan plunged in the 20th century and the Japanese-born ibises became extinct in 2003.

Cooperation between China and Japan on protection of crested ibises started in the 1980s, and since then, China had donated five crested ibises to help rebuild the species in Japan, while Japan had been supporting the protection of the crested ibises habitat in China through governmental and non-governmental projects.

The crested ibises in Japan nowadays are all descendants of those from China. Japan now has some 370 wild crested ibises, most of which are living on the Sado Island.