One of the most remarkable places on Koh Chang is its mangrove forest. Mangroves grow in some 123 countries worldwide, mostly across Southeast Asia, and yet they make up less than 0.4% of the planet’s total forest cover. Which is precisely why I’d call the mangrove forest on Koh Chang a genuinely remarkable place.
To be more precise, there are actually two mangrove areas here — Salak Phet and Salak Khok. Both sit in the island’s south-east, close to one another, but it’s worth understanding that the two are quite different.
- Salak Phet and Salak Khok: two different forests
- The history of Koh Chang’s mangroves
- Why mangroves grow on Koh Chang
- Why the mangroves matter
- When to visit the mangrove forests on Koh Chang
Salak Phet and Salak Khok: two different forests
Salak Phet has the more varied structure, with 12 recorded plant species — mangrove forests typically support only two or three species, so Salak Phet is, in its own way, something of a rarity. It also covers a larger area and opens out into a substantial bay. Salak Khok, by contrast, is smaller, closely tied to one of the local fishing villages, and opens into a far more enclosed bay.
The history of Koh Chang’s mangroves
These mangrove forests can genuinely be called ancient. Research at Salak Khok has uncovered evidence of mangrove growth dating back 6,000 years, with data pointing to the presence of the tidal conditions these plants depend on to survive.
At Salak Phet, scientists have managed to reconstruct the ecosystem’s history across the past 1,500 years. This doesn’t only confirm that the plants existed — it also traces how the territory itself has shifted over time: how the forest’s area shrank as the sea retreated, then expanded again as water levels rose, and how it interacted, throughout, with the surrounding land grasses.
Both mangrove forests are now protected, falling under national park status. Salak Phet has a dedicated nature trail, open to anyone wanting to walk through the forest all the way down to the bay, taking in the trees’ strange, twisted forms and that classic Instagram-worthy view — red wooden walkways threading through the green, with mountains rising in the background.
Historically, mangrove zones have always been closely tied to local settlements and fishing communities, and Salak Khok is protected today by the very village it borders. The local community has built a form of traditional tourism around it, offering visitors a glimpse of daily life, nature, and the fruitful, mutual coexistence between people and this fragile ecosystem.
Why mangroves grow on Koh Chang
Mangroves aren’t merely well-suited to periodic flooding by seawater — they genuinely need it to survive. The south-eastern part of Koh Chang makes an ideal home for mangroves, for two reasons:
- tides here can reach up to a metre in height, which is a considerable amount for such flat terrain;
- the island is exceptionally wet, receiving around 5,000mm of rainfall a year, roughly 90% of it during the rainy season — meaning a huge volume of water arrives in a very short window of time.
This is especially true at Salak Phet, where the area has historically had low salinity, largely thanks to the strong influence of fresh water.
Why the mangroves matter
For Koh Chang, mangroves play a genuinely vital role, closely bound up with the lives of the people who live here. Their ability to respond to shifting water levels, and to move in step with the retreating or advancing sea, helps preserve habitat for people, animals and countless other organisms alike — fish among them, which the local community depends on for its livelihood.
When to visit the mangrove forests on Koh Chang
The best time to visit, in my view, is the middle or tail end of the rainy season, when you can see the trees standing directly in the water. In the dry season, with no fresh water flowing in, overall water levels drop and much of it seeps into the ground, leaving behind what feels like one vast expanse of mud.
The forest is easy to explore at any time of year, thanks to wooden walkways laid out throughout. And even if you’re visiting Koh Chang in January, don’t skip the forest on that account — it’s still well worth seeing.
