More than 20 Bryde's whales have been tallied near Beihai's Weizhou Island in South China's Guangxi Zhuang autonomous region, the first pod of whales found living in China's inshore area.

The pod of whales has been frequently spotted near the island since a group of scientists found six whales around the island during a scientific study in April last year.

According to Chen Bingyao, associate professor of life sciences at Nanjing Normal University, the marine mammals have returned after decades of absence, which indicates an improving marine ecosystem under China's stricter pollution control.

The tourism authority of Weizhou Island launched a regular marine patrol on March 11 with coast guards, to protect the herd of whales and target illegal hunting and killing of the whales, according to Xinhua.

Bryde's whales mainly live in tropical and temperate waters, and hunt small fish as prey. They were first named by Norwegian whaling expert Johan Bryde.