In Qinghai province, footage of animals that had not been seen since the 1990s, due to excessive hunting, has been captured by infrared cameras several times in the past three years. The animals include snow leopards and Chinese mountain cats, both listed as "vulnerable" by the International Union for Conservation of Nature.

In December, seven endangered alpine musk deer, which are classified as "endangered" on the IUCN's Red List of Threatened Species, were sighted in Qinghai's Three-River-Source National Park. Moreover, a herd of about 100 wild red deer under State protection was also observed by local rangers in February.

Similar cases have been reported off China's coast. On June 29, a Bryde's whale, a Class 1 protected species, was sighted by fishermen in Dapeng Bay near Shenzhen, Guangdong province.

Footage of the whale, which had been in the bay for more than a week and had an ample food supply, was taken by a local broadcaster, attracting some 300,000 views.

It was only the second time a whale had appeared in the bay in 16 years. According to the book Chinese Cetaceans, the previous sighting was in 2005 near Sha Tau Kok in Hong Kong.

Liao Baolin, an expert at the Shenzhen Research Institute of Guangdong Ocean University, said the whale's visit was a rare occurrence but was not surprising. The species has high requirements for food and water quality and is usually found in oceans, where there are plenty of fish.

Chen Cheng, who lives in Shenzhen and has noted the marine life population rising in the area, said: "The quality of coastal waters in Shenzhen has improved greatly in the past five years. It's easy to find jellyfish in these waters. I once came across a dolphin, so I hope whales will appear more frequently in the future."