20th Anniversary of World Heritage

With its abundant biodiversity of flora and fauna, existing since ancient times, the Khao Yai forest can be likened to an invaluable treasure that continuously sustains all life. It is a priceless legacy from our ancestors, and the one thing our generation should—and must—do is to pass on this richness as an inheritance to future generations.

For this profound reason, Khao Yai was inscribed as a UNESCO World Heritage site 20 years ago, on July 14, 2005. Khao Yai forms an integral part of the World Heritage of Dong Phayayen-Khao Yai Forest Complex.

1.

What is a World Heritage Site?

A World Heritage Site is an area—which can be a forest, mountain, lake, various structures, or even a city—selected by UNESCO for its outstanding cultural, historical, scientific, or other significance, whether created by humans or nature.

The Dong Phayayen-Khao Yai Forest Complex World Heritage Site spans a total area of 6,152 sq. km. It is recognized as a habitat for rare or endangered animal and plant species, possessing an ecosystem rich in diverse flora and fauna. It encompasses 4 national parks and 1 wildlife sanctuary: Khao Yai National Park, Thap Lan National Park, Pang Sida National Park, Ta Phraya National Park, and Dong Yai Wildlife Sanctuary. The complex features a wide array of forest types, including moist evergreen forest, montane evergreen forest, dry evergreen forest, mixed deciduous forest, dry dipterocarp forest, grasslands, and secondary forest. It boasts over 2,500 plant species, roughly one-sixth of Thailand's total, including 16 endemic species, and 805 wildlife species.

As the Dong Phayayen-Khao Yai Forest Complex celebrates its 20th anniversary as a World Heritage site this year, the Khaoyai Connect team invites you to speak with "Chaiya Huayhongthong," the 58-year-old Chief of Khao Yai National Park. A seasoned forest protector who has served the park for over three years, Chief Chaiya shares his goals and vision for forest management in the current era.

2.

The Park and its 3 Missions

Chief Chaiya began the conversation by outlining the three core missions of Khao Yai National Park: 1. Conservation, 2. Academic Research, and 3. Recreation and Tourism.

"I prioritize conservation," he stated. "Because if we don't conserve, we won't have the resources, and people won't come to visit."

He further elaborated that Khao Yai National Park, ranking third in size nationally at 1.35 million rai (approximately 2,160 sq. km), experiences very minimal encroachment, less than 10,000 rai (16 sq. km). This stands in stark contrast to other areas where encroachment can amount to hundreds of thousands of rai. This success is attributed to the decisive policy of relocating residents during the era of Field Marshal Sarit Thanarat, which has allowed Khao Yai to maintain its richness. There has been no encroachment at all in the upper parts of the park, with only minor issues along its periphery.

"As a World Heritage site, we must maintain high standards. The advantage of being a World Heritage area is like a protective shield for us. Whenever there's a request to undertake any project within the park, it must first pass through the World Heritage Committee. For instance, building a reservoir would require their prior consideration. Any development within the park becomes more challenging. For example, constructing a dam, which requires a significant area, necessitates research, an EIA report (Environmental Impact Assessment), and an analysis of the environmental impact, as well as an assessment of the wildlife present. Because when a dam is built, we don't know which wild animal species might disappear."

3.

Smart Conservation with the Smart Patrol System

Currently, across the entire 1.35 million rai of Khao Yai Forest, there are approximately 200 officials, divided into 30 patrol units, overseeing a total of 8 management zones. Each unit has an appointed assistant in charge. Patrol units are required to spend at least 15 nights per month on overnight patrols in the forest.

Although the number of officials is very small compared to the vastness of the forest, in this era of advanced technology, their work has become significantly more efficient through "Smart Patrols." This quality-based patrolling system in protected forest areas utilizes Geographic Information System (GIS) technology for planning patrols, data collection, and standardized data analysis and processing. Its objective is for patrol units to gather high-quality data from their patrols, such as evidence of illegal logging and poaching, as well as various ecological factors. This data is then combined with technology to deter and prevent the destruction of forest and wildlife resources.

"And nowadays, we can't lie," he explained. "With Smart Patrol, we carry a GPS in our bags. When patrolling, if we find traces of animals or logging, we record the coordinates and statistics. At the end of the month, we hold a meeting to summarize the threats encountered each month."

Illegal Logging by "Tourists"

Chief Chaiya stated that the primary problem encountered in Khao Yai National Park is the illegal logging of two types of wood: Aquilaria wood (or fragrant wood) and Siamese rosewood.

"The current situation reveals that Thais are bringing Cambodians into the park under the guise of tourists. Sometimes we catch them sleeping in tents. When stealing fragrant wood, they scratch the trees and leave them. If you look, the front appears intact, but the back is completely gouged out. When Aquilaria wood is wounded, it produces a resin to cover the wound—that's the part extracted for perfume. And these secretly harvested fragrant wood trees aren't far, just 600 meters behind the visitor center. The gouged trees don't die, but they stop growing. When we apprehend them, we send photos and names to the immigration police (IM). However, it turns out that IM allows them to return, and they even have stamped passports. The problem is, we don't receive cooperation from external agencies," the Chief said, shaking his head.

As for illegal Siamese rosewood logging, groups come equipped with chainsaws to cut and immediately carry away the wood. Most of the cut pieces are about 2 inches wide and 2 meters long. After sawing, they use nails to tie ropes and carry them out. It's understood that this valuable wood is sent to China for carving due to its high price. Park officials use technology to monitor and suppress these illicit activities.

Regarding wildlife, poaching is less common now, perhaps because people no longer prefer consuming wild meat. However, this doesn't mean wildlife has no problems. The current situation shows a concerning decline in the barking deer and sambar deer populations.

4.

Missing Tigers, Missing Balance

From continuous academic research and data, we understand the current status of flora and fauna in Khao Yai National Park, including the types and numbers of species present, and which species are diminishing.

"Currently, Khao Yai has no tigers; they have gone extinct here. Without tigers, our deer and barking deer populations have drastically dwindled because dholes (wild dogs) consume them all. Previously, dholes were preyed upon by tigers, but now with no tigers, dholes thrive, as do elephants and gaurs, due to the absence of the top predator in the food chain. There are now no less than 100 dholes, and if you consider that they hunt all day, it's clear why spotting deer and barking deer now is so rare."

"Dholes are smart and swift; they can even take down gaurs by attacking them from front and back in packs. Deer have no chance of survival."

When asked if this situation was concerning, Chief Chaiya nodded, admitting it was quite alarming. Some nights, he now spots no more than 20 deer, whereas over a decade ago, one could see hundreds in a single night. For example, at Khao Laem Meadow, 4 kilometers from Heo Suwat Waterfall, it was said that the field was once teeming with deer, but now they are rarely seen.

Thus, structures like the "Corridor – Thap Lan Tunnel" on Highway 304 (Kabin Buri-Pak Thong Chai) represent another effort aimed at allowing wildlife, including tigers, to move back and forth.

"We are trying to get tigers to cross the corridor from Thap Lan. But the problem is, they say tigers prefer open forests, not dense ones, and Khao Yai is a dense forest. And if they cross the corridor, there's also a stream blocking their way, making it not easy for tigers to cross. Additionally, food on the other side seems abundant, so they might not want to relocate yet. Currently, they still haven't crossed. The closest paw prints found were about 1 kilometer from the corridor."

Chief Chaiya mentioned that tigers have been absent from Khao Yai Forest for about 20 years. This could be due to extensive hunting in the past, likely including tigers, coupled with a wild boar epidemic that led to many deaths, and it's uncertain if tigers consumed the carcasses.

"The last tiger we found was a carcass at a golf course. If it were poaching, they would have taken the carcass. But this one likely died naturally, as we found a dried carcass. We don't know the cause of death."

When asked if it's possible to release tigers into the park:

"It's uncertain. Ultimately, if there truly are none, we might have to do that. I think releasing them or letting them come naturally wouldn't make a difference. Tigers can survive here because we wouldn't bring Bengal tigers; we'd bring native Indochinese tigers, our original species. Some ask why we don't bring the many tigers from captivity, but they are different breeds, exotic species. All national parks prohibit the introduction of non-native plants and animals. So, we either have to wait for natural tigers to cross over, or we might have to capture and relocate them. Right now, everyone wants tigers to return to Khao Yai to restore balance, to prey on dholes, and to help manage elephant and gaur calf populations."

5.

Outstanding Recreation: 7 Popular Hiking Trails

Statistics show a continuous increase in tourists visiting Khao Yai National Park. In 2023, there were 1.4 million visitors, with 50,000 being foreigners. In 2024, the number rose to 1.88 million visitors, including 100,000 foreigners. The peak tourist season is from October to January, with the highest single-day count reaching 20,000 visitors.

"Apart from Westerners, foreign tourists visiting Khao Yai nowadays also include Japanese, Chinese, and Singaporeans. Most come for wildlife viewing, like birds and elephants, and for hiking."

Chief Chaiya noted that Khao Yai boasts numerous attractions, including Heo Narok Waterfall, Heo Suwat Waterfall, Pha Trom Jai Cliff, Pha Diao Dai Cliff, various viewpoints, and 7 hiking trails. This allows for crowd distribution even with a high number of visitors. There are 6 entrance fee collection points: Nernhorm Gate, Chao Por Gate, Takro Waterfall, Kaeng Hin Phoeng, Sarika Waterfall, and Krok E-Dok Waterfall.

Hiking is gaining immense popularity among tourists. There are 7 trails in total, ranging from 1.2 to 8 kilometers in length, taking approximately 45 minutes to 6 hours to complete. All routes are round-trip, with no overnight stays permitted. For this activity, visitors can contact park officials at the Khao Yai National Park Visitor Center or by phone at 086-0926529 or 081-0639241.

Trail 1: "Visitor Center – Kong Kaeo Waterfall"

This 1.2-kilometer loop trail takes 45 minutes to 1 hour to complete. As the shortest route, it is suitable for all ages. Along the way, visitors may encounter Aquilaria trees (fragrant wood), which release a delightful aroma when burned, and might spot wildlife such as white-handed gibbons, pileated gibbons, and various bird species.

Trail 2: "Pha Kluay Mai Waterfall – Heo Suwat Waterfall"

This 3-kilometer trail, taking 2 hours to complete, connects the two waterfalls. It meanders along the Lam Ta Khong stream, passing through alternating forest types, including dry evergreen forest. Visitors may discover Thismia kelabitiana, a newly discovered species of stone flower that emerges from the water, as well as red rattan which produces distinctive long red inflorescences near the waterfall in April.

Trail 3: "Km. 33 – Nong Phak Chi"

This 3.3-kilometer trail, taking 2.5-3 hours, offers an experience of diverse forest types, including lush dry evergreen forest, secondary forest, and grasslands. It features large shade trees such as banyan and Java plum, and the giant Holy Basil (Ocimum sanctum), a plant endemic only to the Dong Phayayen forest complex. This route is a foraging ground for elephants and gaurs, and animal tracks may be found throughout. Occasionally, visitors might spot hornbills nesting in tree hollows or gibbons swinging through the canopy, feeding on fruits.

Trail 4: "Dong Tiew – Sai Sorn Reservoir"

This 2.7-kilometer one-way trail, taking 1.5-2 hours, leads to Sai Sorn Reservoir, a beautiful sunset viewpoint. During the rainy season, various flowers like Dancing Ladies (Globba spp.), Begonias, and Hermit's Tea (Clerodendrum chinense) can be found. The highlight of this trail is a centuries-old giant Samphong tree (Tetrameles nudiflora).

Trail 5: "Dong Tiew – Nong Phak Chi"

This 5-kilometer trail, taking 3 hours, again features the centuries-old giant Samphong tree as its highlight. During the rainy season, visitors can observe forest mushrooms of various shapes and colors. This trail is a foraging area for many wildlife species, including elephants, bears, hornbills, and gibbons.

Trail 6: "Visitor Center – Heo Suwat Waterfall"

This 8-kilometer trail, taking 6 hours, is considered a significant natural lesson due to its considerable length. The forest consists of moist and dry evergreen forest interspersed with bamboo groves. It boasts many valuable plant species, such as Siamese rosewood, Aquilaria (fragrant wood), and dense fern patches. Wildlife is abundant, including elephants, gibbons, Asiatic black bears, and hornbills.

Trail 7: "200 Years of Thai-U.S. Relations"

This 2-kilometer trail, taking 1.5 hours, is the park's newest route, established to celebrate the long-standing relationship between the two countries. It adheres to U.S. National Park standards under the Sister Parks Arrangement for Resources and Knowledge Sharing (SPARK) program. Along the trail, visitors will discover the beauty of diverse forest ecosystems, including dry evergreen forest, secondary forest, and expansive grasslands. Commonly sighted wildlife along this route includes Siamese fireback pheasants and Kalij pheasants.

For all 7 trails, visitors must contact the visitor center beforehand, as some routes require a park official to accompany the group, while others do not.

6.

The Heart of a Forest Worker

Chief Chaiya believes that the department needs a dedicated team of officials to inspect what each national park needs to develop. For instance, the roads in Khao Yai National Park have not been improved for many years, especially on the Nernhorm side, where they are in very poor condition, and the park cannot undertake repairs independently.

Another crucial issue is tourist insurance. Many times, when incidents occur, the department lacks funds for compensation, such as the case of a Filipino tourist hit by a rockslide at Heo Narok Waterfall. The department needs to consider implementing mandatory insurance. Currently, insurance is an optional 10 baht add-on upon park entry, but discussions are underway to include the insurance fee in the ticket price in the future, which would streamline operations.

"I'm not worried about wildlife care; I'm concerned about the deteriorating public infrastructure that I can't repair. I can fix staff housing or the water supply, but the problem I can't fix is the 40-kilometer-long road, which is used by 7,000-8,000 people daily. Anyone driving through will see signs warning of falling rocks—that area is prone to collapse. That's what I worry about. This road was built and handed over to us, making it difficult to request repair budgets later on, and the budget required is enormous. Another concern is trees that are ready to fall because they lean towards the light; I fear they might fall on tourists. We can partly address this by cutting down hollow or heavily leaning trees, but we cannot maintain a 40-kilometer road on our own. This is where insurance should help."

7.

Celebrating 20 Years of UNESCO World Heritage

With an elevation of 800 meters above sea level, its abundance, and biodiversity, Khao Yai stands out remarkably, attracting people to both live and visit. Therefore, for Pak Chong town, Khao Yai is considered the principal entity that all lives must respect.

Regarding what makes Khao Yai's 20th UNESCO World Heritage anniversary special, Chief Chaiya mentioned that Khao Yai National Park typically holds a merit-making ceremony every year on September 18th. However, this year is special: a major event might be held concurrently with the 20th anniversary of its World Heritage status on July 31st, which is Ranger Day (World Forest Rangers Day). This event was previously hosted in Khao Yai in 2022, and it is expected to return this year. It will be an event where various departments within the Ministry of Natural Resources and Environment will gather to commemorate forest protection, a day for forest rangers to feel proud.

Because there are forests, there is life. The 20th anniversary of its World Heritage status serves as a reminder to recognize the importance of forests, to help preserve this abundant forest — a legacy we received — and to pass it on to future generations for a continuous, good life.

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