Thailand is striving to remain the top adventure and eco-tourism destination in the region as neighbouring countries begin to profit from the environmental tourism boom.
The tourism industry in the Greater Mekong Subregion (GMS) was the fastest growing in Asia-Pacific in 2013. The area recorded a 17% increase in international tourist arrivals from 2012, according to statistics from the Bangkok-based Mekong Tourism Coordinating Office.
The Asia-Pacific tourism market more than doubled in recent years, while travel between Asean countries rose by 11% during the same period. International tourist arrivals to the GMS have grown an average of 12% a year since 2002.
Millions of travellers coming to the region have been enjoying eco-tourism and adventure activities in Thailand, Myanmar, Laos, Vietnam and Cambodia.
The major sources of arrivals for this niche market during the past decade have been Britain, the Netherlands, France, Scandinavia, the US, Australia and New Zealand.
But emerging economies like India, South Korea, Brazil, the Middle East and China are providing an increasingly large portion of travellers.
"For Thailand, eco-tourism and adventure will still represent 10-20% of the entire sector," said Neeracha Wongmasa, president of the Thai Eco-tourism and Adventure Travel Association.
This year, Thailand hopes to welcome 800,000 foreign eco-tourism visitors, increasing to more than 1 million visitors over the next few years. Officials expect to welcome 34 million foreign tourists in 2017 as Thailand remains one of the world's top 10 destinations.
"The country will have to tackle a new decade of adventure and eco-tourism," Ms Neeracha said. "This segment is booming in all GMS countries."
She said her group recognises that while Thailand is able to attract tourists with its unique culture and natural sites, major competitors in the region such as Vietnam, Myanmar and Laos are moving to strengthen their marketing strategies at international tourism events.
In 2013, she said, the GMS received 51.7 million international tourist arrivals -- about 3% of the global market. More than 60% of these international visitors originated in Asia-Pacific, with the greater part coming from China, Japan, Malaysia, South Korea, Thailand and Vietnam.
China, for example, was the largest or second-largest source of tourists travelling to Cambodia, Myanmar, Thailand and Vietnam, Ms Neeracha said.
The Adventure Travel Trade Association deems the GMS ideal for adventure tourism, defined as a trip that "includes at least two of three elements: physical activity, natural environment and cultural immersion".
The Mekong Tourism Coordinating Office notes that while Thailand's share of total GMS arrivals fell from 61% in 2004 to 51% in 2013, the country has remained the gateway to the subregion.
At the recent Thailand Travel Mart Plus Amazing Gateway to the Greater Mekong Subregion 2017, the country's largest travel mart event, tourism buyers from Poland, Laos and India expressed interest in the growing adventure and eco-tourism business in GSM countries.
Operators said tourists are now directly entering Myanmar, Laos, Vietnam and Cambodia as more flights become available.
"This trend may have a negative effect on Thailand's tourism, because many tourists will fly directly to their destinations instead of making a stopover here, as many of them did in the past," said one executive of a tour operator from India.
Some travel firms have suggested Thailand focus on upscale markets if it wants to remain a major destination on the global map. Thanks to reasonable costs, the country has the potential to grow in sectors like medical tourism, sports, eco-tourism, cruise and water activities, gastronomy and Mice (meetings, incentives, conferences and exhibitions).
"The cost of travelling to Thailand and the Mekong region is 50% lower than that of travel to Singapore or Europe," said Vikrant Bhardwaj, an executive of India-based Trans Destinations.
More than 350 delegates and tourism experts are expected to gather for the Mekong Tourism Forum in Luang Prabang, Laos. During the June 6-9 meeting, attendants will discuss how to promote tourism in the region more broadly.
Experts and stakeholders have defined a five-prong strategy for long-term development in the region: human resources, improvement of tourism infrastructure, enhancement of visitor experiences and services, creative marketing and promotion, and facilitation of regional travel.
To push eco-tourism at the international level, the Thai Eco-tourism and Adventure Travel Association plans to visit Singapore schools to publicise Thailand's eco-tourism experiences. The group will also attend tourism events in European markets.