NANNING, May 13 (Xinhua) -- A research team from Peking University has found between 110 and 122 Indo-Pacific hump-backed dolphins in the waters of Qinzhou Bay in the Beibu Gulf, off the the southern coast of China.

It is the largest group of its kind to be sighted in the Beibu Gulf in recent years.

The majority of the rare dolphins we spotted were adults, said a research fellow with the Qinzhou Bay Indo-Pacific Hump-Backed Dolphins Research Center of Peking University.

Experts say that the healthy ecological environment is a key reason for the increase in the population of the Indo-Pacific hump-backed dolphins.

Indo-Pacific hump-backed dolphins are found from northern Australia and Indonesia to southern China, and around the coastal rim of the Indian Ocean to southern Africa. The dolphins, whose colors range from black and grey to white and red, are inhabitants of tropical to warm temperate coastal waters and they can enter rivers, estuaries and mangroves.

They are listed for top state protection in China.

"We fishing people consider the hump-backed dolphins as signs of good luck," Pei Qiangting, a resident from Sanniangwan Village of Qinnan District of Qinzhou City, "If there is a bad weather on the sea, dolphins can warn us. Therefore, we should work to protect them."

According to Su Yun, a local official with the Sanniangwan tourist administrative zone, large ferryboats are banned from entering the Sanniangwan seaside resort to avoid causing harm to the dolphins.