Relict gulls seen at Hongjiannao Lake in Shenmu, Shaanxi

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)

Relict gulls (larus relictus) are seen at the Hongjiannao Lake in Shenmu, northwest China's Shaanxi Province, May 28, 2020. The Hongjiannao Lake, a desert freshwater lake in Shenmu, attracts lots of relict gulls to inhabit and multiply here from April to August each year. (Xinhua/Liu Xiao)