Changing Planet

Cambodia: The Last Hope for Iconic Wildlife at the Brink?

The Mekong River is the 12th longest river in the world and the third most biodiverse river in terms of fish next to the Amazon and the Congo. It boasts the world’s largest inland fishery, providing food and livelihood for millions of people. It is a transboundary river that runs through six countries: China, Myanmar, Laos, Thailand, Cambodia and Vietnam, and supports hundreds of extraordinary species –- from birds to mammals, reptiles, and fish. It is also important habitat and the last remaining stronghold for species at the brink of extinction, including the giant freshwater stingray, giant ibis, Siamese crocodile, and the Mekong giant catfish. Since it is a transboundary river, there is a need for people to work together for the effective conservation and management of the river ecosystem.

As part of National Geographic’s Mentorship Program, I had the chance to participate in a Workshop on Saving Species on the Edge of Extinction, co-organized by my mentor, Dr. Zeb Hogan. The workshop was part of the USAID-funded Wonders of the Mekong project, a joint initiative that seeks to understand and share the value of the Mekong River ecosystem.

A group photo with conservation practitioners from Laos, Thailand, Cambodia and Vietnam. Photo courtesy of Zeb Hogan.

The workshop brought together conservation practitioners working throughout the Mekong Region into one meeting to talk about their research experiences, the technologies and methodologies they have been using, their conservation actions, and the challenges that they face in trying to address wildlife trafficking, species population declines, among other conservation issues. The workshop also highlighted the need for a strong multidisciplinary network of scientists, educators, filmmakers and other conservation practitioners, for a more holistic approach in conservation and management.

Since most of my experience is related to the marine ecosystem, attending the workshop was my first real experience with issues related to freshwater ecology and conservation. I learned about Freshwater Fish Conservation Zones (FCZs), which are similar to marine protected areas. While there are many efforts in trying to establish FCZs in different river systems, it is regarded as a new strategy. Indeed, freshwater ecology and conservation is relatively a newer field compared to marine ecology. This is why it is recommended that more studies should be done to have a more in depth understanding of these ecosystems, which can ultimately inform management.

Cruising along the Tonle Sap River with my mentor, Zeb Hogan, while learning about more about this important waterway. Photo courtesy of Erina Molina

After the workshop, I was able to visit Zeb Hogan’s study site along with Tach Phanara, a research staff from the Institute of Fisheries and Research Development Institute (IFReDI) of Cambodia. We cruised along the Tonle Sap River while learning about the importance of this river system. The Tonle Sap  is a river connecting the Tonle Sap Lake with the Mekong River. Since the Tonle Sap Lake is a breeding and spawning ground of fish species, the Tonle Sap River is an important corridor for fish species migrating into the Mekong River. Another interesting thing I learned about this river is that the flow changes direction every season. During the rainy season, the river flows from the Mekong River into the Tonle Sap Lake, while the river flows from the lake into the Mekong River during the dry season, which is the time when I visited the river.

The Mekong river is home to the critically endangered Mekong Giant Catfish. Photo courtesy of Zeb Hogan.

We visited the Bagnet or Dai Fishery along the Tonle Sap River to see their catch. This is a type of stationary fishing strategy that catches fish as they migrate down the river.

We also made a quick trip to the site along the Mekong River where Phanara collects fish larval samples for research. When we were there, he mentioned that they found that 70 percent of the fish larva manages to go into the Tonle Sap lake, while 30 percent of the larva continue and travel to the Lower Mekong River. This may signify that these fish know that the lake is the best place to grow and feed!

As an environmental scientist, it was great to see and learn more about the freshwater ecosystem through this mentorship travel experience. Attending the workshop indeed strengthened the idea that conservation is not just science; it covers different fields from scientists, to educators, filmmakers, and other conservation practitioners.

Fishers in the Tonle Sap River. Photo by Erina Molina.

Seeing Zeb in the field with the local fishers also highlights that it is essential to have a good relationship with local communities to foster stewardship from the people on the ground. Indeed, this means that everyone has a role to take part in conservation.

A photo with Zeb Hogan, my mentor and the principal investigator of the Wonders of the Mekong Project. Photo courtesy of Zeb Hogan.

Please watch my videos about this experience:

Cruising along the Tonle Sap River with my mentor, Zeb Hogan, while learning about it. 

Wonders of the Mekong.

Erina is currently taking up Masters in Environmental Science at the University of the Philippines-Diliman. As a National Geographic Young Explorer, she did further research in the Northern part of the Philippines exploring on possible shifting baseline syndrome in the context of examining vulnerable and locally extinct reef fish species. She wants to use this anecdotal evidence from fishers' knowledge and convert it to hard data which will be useful in fisheries management.

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