"The air-seat capacity from China into Northeast Asia, including Macao, Taiwan and Hong Kong, is about three times the size of its equivalent into Southeast Asia. Korea is probably the main beneficiary and has been experiencing consistently high growth out of China."

Institute for Tourism Studies researcher Jae Yeon Choe says: "While preferences for easiness of visa procedures and air service expansion－such as nonstop flights－are factors, Korea's and Japan's pop, fashion and food culture continue to attract Chinese visitors."

IT developer Cheng Wei says his parents wouldn't "let" him visit Vietnam over the National Day holidays.

But he enjoyed Korea two weeks before on his first international trip.

"Korea is nearer than Vietnam," the Beijinger says.

"Flights are cheaper, and it's more developed."

Singapore is the most developed Southeast Asian destination to suffer from the tapering off of Chinese visitors. But industry insiders say that has more to do with Chinese policy than Singapore's positioning as a gateway to other destinations.

"With China exercising closer scrutiny on official government junkets and corruption, Singapore has lost some attraction," Choe explains.

"Gambling was a big draw."

King says Southeast Asian countries have "adopted separate approaches" to deal with the drop.

"Singapore has presented itself in China as a single standalone destination as a means of distinguishing itself from the trouble occurring in neighboring Malaysia," he says.

Chinese tourism to Malaysia dropped 9 percent to 850,877 between January and June compared with the same period of 2013, following years of growth, Tourism Malaysia's general director Dato' Mirza Mohammad Taiyab says.

He believes the dip to be temporary.

Malaysia has responded by studying Chinese travel preferences according to regions and is tailoring marketing according to specific locations, he explains. It's also staging social media campaigns focused on safety; introducing new products and packages; developing charter flights; and marketing more toward second- and third-tier cities.

"Malaysia's priority is to regain the goodwill and friendship of the Chinese people," Taiyab says.

"We are confident that the tourist flow from China will return to normal soon."

King says Thailand has been "particularly active" in courting Chinese tourists.

"(It's) waiving visa fees; launching special retail offers; partnering with Chinese travel agents to develop appealing packages; lessening import duties on luxuries; and stimulating flights to airports away from Bangkok.

Indonesia has started a Chinese-language website. "Indonesia has emerged as the region's main beneficiary of neighboring countries' decline.

Outbound tourism to the country grew 22 percent in the first half of the year, King says.