Photo taken on Jan. 13, 2019 shows red-billed gulls at Cuihu Park in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 11, 2019 shows red-billed gulls at Dianchi Lake in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 13, 2019 shows red-billed gulls at Cuihu Park in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 11, 2019 shows red-billed gulls at Dianchi Lake in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 4, 2019 shows a red-billed gull at Dianchi Lake in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 4, 2019 shows red-billed gulls at Dianchi Lake in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 7, 2019 shows red-billed gulls at Cuihu Park in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 4, 2019 shows red-billed gulls at Dianchi Lake in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 11, 2019 shows red-billed gulls at Dianchi Lake in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)
Photo taken on Jan. 7, 2019 shows red-billed gulls at Cuihu Park in Kunming, capital of southwest China's Yunnan Province. (Xinhua/Yang Zongyou)