Tonle Sap: The Giant Lake of Cambodia and its Unique Ecosystem
Discover Tonle Sap Lake, a natural wonder located at the heart of Cambodia. This unique lake is essential to the survival and well-being of millions of people, as well as a multitude of animal and plant species. Explore its ecological secrets, picturesque floating villages, rich diversity of fish, and the challenges it faces.
The Ecological Importance of Tonle Sap
Tonle Sap Lake has been recognized by UNESCO for its ecological importance. It houses an incredible diversity of flora and fauna, some of which are unique to this region. The forest that surrounds the lake is also a valuable habitat for many endangered bird species, such as those that can be observed in the Prek Toal bird sanctuary.
The Natural Phenomenon of Tonle Sap
The unique hydrological system of Tonle Sap is a true natural phenomenon. The lake is fed by the waters of the great Mekong River. During the rainy season, the water level rises and the lake expands over thousands of km2. Conversely, during the dry season, the volume of water decreases considerably, revealing fertile land for agriculture.
This annual cycle creates an exceptionally rich ecosystem, housing a great variety of aquatic and terrestrial species. The life of the lake’s inhabitants, particularly fishermen and farmers, is influenced by these seasonal changes.
Fish Species and Fishing
Tonle Sap is a real treasure for fish enthusiasts. It has a great diversity of species, some of which are endemic to this region. Among the most famous are the giant Mekong catfish and the snakehead fish.
Fishing is an essential activity for the local population, who depend on the lake for their subsistence. In fact, nearly 75% of Cambodians’ protein intake comes from fish in Tonle Sap.
Tourism Activities
Visiting Tonle Sap is a unique experience not to be missed during a trip to Cambodia. Among the must-see attractions are the floating villages, such as Chong Khneas and Prek Toal, where you will discover the daily life of the people living on the water in floating houses.
In addition, the Prek Toal bird sanctuary is a paradise for bird enthusiasts and ecotourists. You can also explore the surrounding forests by boat or kayak to observe the local fauna and flora up close.
Challenges and Preservation of Tonle Sap
Unfortunately, this ecological gem is threatened by various factors, such as climate change, dam construction on the Mekong, and overexploitation of natural resources. Preserving Tonle Sap is essential to ensure the survival of the species that live there, as well as the well-being of local populations.
Efforts are being made to protect and conserve this precious ecosystem, particularly through local and international organizations working hand in hand with local communities.
In conclusion, Tonle Sap Lake is a multifaceted natural wonder, offering a fascinating glimpse into life in Cambodia and the delicate balance between human needs and environmental preservation. Discover this ecological richness on your next trip and support initiatives aimed at preserving this unique ecosystem for future generations.

Distribution of costs
%
Transport, food, qualified guides
%
Income for environmental education
%
Direct income for villagers (local development)
%
Entrance fee to the bird sanctuary and Environmental responsible contribution cost
Tours
According to your desires and the period of your visit, you will find here the panel of our itineraries. There is something for everyone. For more information, contact us.
The full package
in a day
This tour gives you the opportunity to go birding in the sanctuary and have an experience of the village itself.

Full day tour
From 6am to 5pm

Birding with a
Certified Osmose guide

September to March
Immersion
into tradition
Get ready to dig into Prek Toal’s deepest customs and live the very unique “life on water” experience.

Overnight stay

Cooking class

All year round
A glimpse of life on water
This day tour will give you an insight of the floating village life from a boat to another, understanding the local customs.

Full day tour
from 8am to 5pm

Weaving class

All year round
A Ranger’s Life
This overnight stay tour is made for the ones passionate about birding, who wouldn’t miss the opportunity of digging into Prek Toal’s mind-blowing customs.

Overnight stay

Birding with a
Certified Osmose guide

September to March

Hello, I’m Osmi, the super bottle that will accompany you during the tour.
In an eco-friendly approach, Osmose no longer uses plastic bottles.
To ensure my hygiene, I am boiled at high temperature and cleaned after each visit.
My water is as good as bottled water, clean and fresh.
Thank you for your support, you help us protect the environment!
Sincerely, Osmi
Price grid
Up to 30 pax, fixed price. Above, please ask for a quotation.
French Guide : 15$ supp. Free for children < 5. From 6 to 12 years -25%.
The full package in a day

Full day tour
From 6am to 5pm

Birding with a
Certified Osmose guide

September to March

It’s 6.00 am…
We’ll pick you up at your hotel, take you to Meichrey’s port and board you to Prek Toal’s Village. Change boats and off to the bird sanctuary!
8.30am, birdwatching
Accompanied by your very own certified Osmose guide, cruise through the protected bird sanctuary and discover species of all kinds: Pelicans, Asian open bills, Greater Adjutant, etc.
12.30 pm,
Take a break:
Once we’re back at our Community platforms, have a great lunch prepared by professionally trained cooking members!
2.00 pm,
Meet the locals:
Visit the environmental education class and the water hyacinth workshop. See the village through the authentic experience of boarding a traditional Khmer paddle boat. From a floating family’s house to the floating gardens, fish farms and shops, discover how local communities have marvelously adapted to living on water.
3.30 pm,
Return home
Return to your hotel, full of memories around 5.30pm!
Immersion into tradition

Overnight stay

Cooking class

All year round

It’s 1.30 pm…
We’ll pick you up at your hotel, take you to Meichrey’s port and board you to Prek Toal’s Village.
15.30 pm,
Drop your bags:
On your arrival at the floating village, drop your bags at your family’s home-stay residence.
16.00 pm,
Culinary goodness for a beautiful break:
You will be given an intense Khmer cooking lesson and invited to savor your freshly made dishes for dinner, while taking time to admire the beautiful sunset on offer.
Day two, become a villager!
7.30 am,
Let’s wake up
8.00 am,
In depth discovery,
After having breakfast, enjoy an authentic experience, seeing the village on board a local’s traditional paddle boat. Understanding what they do from a floating family’s house through the floating gardens, fish farms and shops. Discover how local communities have marvelously adapted to living on water. Take a look at the village from high above by stopping at the Environmental Research Station.
10.30 am,
Local projects,
Once we’re back at our platforms, visit the local community projects the environmental education class and the water hyacinth workshop. Learn how to make your very own souvenir of the trip with a weaving class
13.00 am,
Return home
Return to your hotel, full of memories around 15.00pm!
A glimpse of life on water

Full day tour
from 8am to 5pm

Weaving class

All year round

It’s 8.00 am…
We’ll pick you up at your hotel, take you to Meichrey’s port and board you to Prek Toal’s Village.
10.00 am,
Paddle through the village
Accompanied by your very own certified Osmose guide, see the village through the authentic experience on board a traditional Khmer paddle boat. From a floating family’s house through the floating gardens, fish farms and shops, discover how local communities have marvelously adapted to living on water.
Take a look at the village from high above by stopping at the Environmental Research Station.
12.00 pm,
Take a break:
Once we’re back at our CBT platforms, have a great lunch prepared by professionally trained cooking members!
2.00 pm,
Visit the local community projects:
Visit the local community projects the environmental education class and the water hyacinth workshop. You’ll get to bring home your own souvenir of the day by getting a sewing class with the girls!
5.00 pm,
Back at the hotel, full of memories:
Return to your hotel, full of memories around 5.30pm!
Le tour du Ranger

Overnight stay

Birding with a
Certified Osmose guide

September to March

It’s 1.30 pm…
We’ll pick you up at your hotel, take you to Meichrey’s port and board you to Prek Toal’s Village.
Upon your arrival, visit the environmental education class and the water hyacinth workshop.
Hop on the next boat! See the village through the authentic experience on board a traditional Khmer paddle boat. From a floating family’s house through the floating gardens, fish farms and shops, discover how local communities have marvelously adapted to living on water.
16.30 pm,
Culinary goodness for a beautiful break:
You will be given an intense Khmer cooking lesson to then savor your freshly made dishes for dinner, while taking time to admire the beautiful sunset on offer.
Day two, It’s time to go bird watching!
6.30 am,
The conservation
Accompanied by your very own certified Osmose guide, cruise through the protected bird sanctuary and explore all it has to offer with your guide and ranger.
12.00 pm,
Take a break:
Take a break for lunch and have your last bite on a floating platform.
1.00 pm,
Return home
Return to your hotel, full of memories around 3.30pm!
Tour Guides
Our Osmose guides receive a certification after a training of 3 months, renewed every 2 years.
Conscious of the contribution of this training, the guides are voluntary to participate and acquire new knowledge.
For 3 months they are taught all the secrets of Tonle Sap Lake and its biodiversity (fauna, flora, ecosystem etc.) Not to mention an indispensable chapter on threats to the lake. It is an active training with bird watching days to acquire specific knowledge and skills in ornithology. Finally, a chapter on Osmose and its various projects is given to them so that they can spread information about our actions to visitors.
Here is the portrait of 4 of our most active guides,
anglophone and francophone.
SOVANN
(English speaker)
“My name is Sovann. I was born in Kompong Chhnang province and moved to Siem Reap province in 2005. At that time, I had heard about Osmose’s work to protect the Tonle Sap lake environment and its integrated projects of environmental education, ecotourism and local livelihood development. I was very interested in the conservation and protection of wildlife and environment and wished to be a part of the movement. I’m very grateful to Osmose that in 2011 they allowed me to join the team after successfully completing my training as a certified guide.
During my time with OSMOSE, I have learned more and more about Tonle Sap’s complex ecosystem, the local’s daily lives and their uncommon culture.
I like my job so much because I love wildlife and we support Prek Toal’s local economy by providing alternative income through eco-tourism. I am happy to share my knowledge and experience to the ones curious to discover more about Tonle Sap’s lake conservation and local life.“
BUNCHANG
(English speaker)
“My name is Bunchang, I am 38 years old and come from a small village down by the lake in the south of Siem Reap city. I’ve been working for Osmose NGO for 8 years now. I’ve been having a beautiful experience and learning a lot about local peoples lives, birding and nature.
I’ve understood much more about conservation work. I feel useful as I can work to prevent the endangerment of Cambodian wildlife. One day, if I have the opportunity, I would like to build up the capacity of nature and conservation resources and contribute the best I can to the local’s education to ensure a better future for the people in the community.
What I love the most about working for Osmose NGO is that I can help people all around the world to know and understand my country’s natural resources. The Tonle Sap lake’s local peoples livelihoods, birding and culture. It is so beautiful and attractive to me!“
DARA
(English and French speaker)
“Je m’appelle KHIM Dara, je suis née dans la province de Battambang, située à environ 90 km au sud-ouest de la province de Siem Reap. Je suis à Siem Reap depuis 15 ans. Après avoir obtenu mon diplôme universitaire, j’ai expérimenté de nombreux travails au cours de cette période.
Enfin, j’ai été recruté comme éco-guide par Osmose en 2011, j’ai suivi une formation de trois mois sur l’écotourisme : Système Tonle Sap, Education à l’environnement, communauté Osmose et spécialiste de l’observation des oiseaux, etc.
J’ai travaillé pendant 7 ans dans les bureaux d’Osmose, en tant que responsable de la réservation francophone mais aussi en tant qu’éco-guide. Je ne travaille plus dans les bureaux depuis 2018 mais je continue d’offrir mes services de guide. J’ai vraiment apprécié ces expériences exceptionnelles et ce travail pour la communauté et l’environnement.“
Mr SUM
(French speaker)
“Je m’appelle Sum , j’ai 65 ans et je vis non loin du village Veal. Cela fait depuis 2013 que j’ai était certifié comme guide Osmose et suis très heureux de participer aux projets de cette organisation car je trouve qu’il y a un réel impact et de belles valeurs.
Je suis reconnaissant d’être cambodgien, état aussi connu sous le nom “d’Etat d’or regorgeant de richesses naturelles.”
Le grand lac qu’est le Tonle Sap, chef d’œuvre de la nature, dans lequel l’eau du Mékong se déverse et se retire, régule la nature à travers les saisons et protège ses proches habitants d’inondations et de sècheresse.
A l’intérieur de cette communauté, Osmose a créé des emplois pour les plus démunis, de nouveaux revenus pour les villageois. Une influence positive pour la communauté sur des aspects pressants : celles de la conservation nécessaire des oiseaux, de l’environnement et de la pollution.
Le Tonle est le cœur du Cambodge, Angkor Wat le porteur de notre héritage culturel. Un visiteur au Cambodge devrait toujours au moins visiter ces deux merveilles.“
Photo Gallery
Your reviews


AnneBE100
Reviewed March 6, 2023
Amazing and worthwhile
We had an amazing day to Prek Toal village and bird sanctuary. Everything was well organised, punctual and as described in their tourprogram. Our guide, mister Va, was simple amazing. He was extremely knowledgeable and was happy to answer all of our many questions. He was very cheerful and attentive.
We approached Osmose in their office on a closed day but there was a lady who still got us in contact and we could arrange everything.
We love nature, quiet and just seeing the lives of people how it is so this day was truly perfect. We are a couple with a child of 7y old and we did the tour with another youngh couple we knew. This is suitable for youngh and old.
After 30min private minibus drive we arrived to the small fishing port were we had a short look around the fishsorting and boarded a boat (roof shade). We were about 1h on the water before we reached prek toal village (during this hour we passed another mobile floating village and beautiful river scenery with lots of fishing areas). In prek toal ( floating village which doesnt change location, all buildings floating and few stone buildings build on the riverbank like police office and mayors house) we climbed the local ranger building for a view and switched to a smaller motorboat (no shade) and entered the birdsanctuary. This was beautiful. Osmose supplied all of us with good quality binoculars and we saw a wide range of birds (and some monkeys!). The dry season is best for that. During the 2,5hours in the sanctuary we also climed the most amazing birdwatching treehouse and saw with a telescope they brought a nesting family of pelicans and maribu.
When we returned to the village we had lunch at a restaurant run by local women (delicious and plenty) and visited a hyacintstem weaving project were women make handicraft to sell and provide income. On peddleboats we continued to visit a floating crocodile farm and we saw local people fishfarming. The trip back was full of impressions again of local life. They day left us very happy and fulfilled. We loved it, our daugther loved it. We learned a lot and feel we understand now much better things we were just looking at before. Thank you Osmose and mister Va for this wonderful experience.
And… maybe not the cheapest but very valuable that with your money you support local people, projects and conservation of this beautiful area.
Date of experience: March 2023

Clemence
Reviewed March 6, 2023
Great experience!
We did a one day tour with Osmose and we loved it. We enjoyed a lot watching all kind of different birds and learning about the ecosystem of the Tonle Sap. The boat ride in the reserve was a unique moment, the nature is beautiful and well protected. We also liked the visit of the floating village of Prek Toal. It was incredible discovering how people live in the water. Finaly our guide Va (not sure if I spelled it right..) was great and very passionate about his work. This day will definitely be the highlight of our trip in Cambodia.
Date of experience: March 2023

Thomas D
Reviewed January 4, 2023
Fantastic experience & organization
We had the chance to discover the Tonle Sap during 1 day with Man who is a bird lovers and could point a lot of different species to us during the bird discovery tour. Then the visit of the village makes us wonder about how people live so connected to the lake. Osmose is doing a great job their! We recommend to have lunch at Osmose floating house:). Thanks and all the best!
Date of experience: January 2023

Reviewed January 2, 2023
Memorable day on Tonle Sap
Fantastic day on the water, that gives you a real understanding of the importance of Tonle Sap and the Mekong to Siem Reap, Angkor Wat and the way of life in the area. Well worth the effort and time to go a little off the beaten path to visit the bird sanctuary and Prek Toal floating village. Lunch is at a specially created “cafe” by Osmose staffed by local women from the village – clean and delicious. Our guide was knowledgeable and easy to talk to with, which made for a fun and interesting day! Highly recommend!
Date of experience: Dec 2022

Reviewed December 14, 2022
A fantastic tour
Had a fantastic day with Nan at Tonle Sap. It’s clear that Nan is so passionate about what he does. This tour was a huge highlight for my time in Cambodia. It was amazing to learn more about the birds in the area. Would highly recommend!
Date of experience: December 2022

CONTACT US
House # 0203, Group 8, Phum Wat Damnak, Sangkat Salakamreuk, Siem Reap, Cambodia PO Box 93-118

+855 12 832 812 / +855 63 765 506
contact@osmosetonlesap.com
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