Join Wild Chronicles along the Mekong River in Cambodia where National Geographic Emerging Explorer Zeb Hogan races against time to save the critically endangered giant catfish. Weighing in at more than 600 pounds, these behemoths may be the world's largest freshwater fish. But overfishing and dam building threaten to render this Mekong icon extinct.

  1. How much fish is harvested annually from the Mekong River?

    • Answer

      More than two million tons of fish are harvested from the Mekong River every year.

  2. The Mekong is home to more large fishes than any other river. Why?

    • Answer

      The size and length of the river provide fish plenty of room to grow.

  3. How do Zeb and other researchers estimate the number of giant catfish in the Mekong?

    • Answer

      Researchers base their estimates on the number of fish caught every year.

  4. Zeb does most of his work with the giant catfish in Cambodia. However, the fish's migration does not begin there. Where does it start?

    • Answer

      The only known spawning ground of the giant catfish is in northern Thailand.

  5. How is Zeb helping educate Cambodian children about the importance of the giant catfish?

    • Answer

      Zeb has produced an illustrated children's book about the migration of the giant catfish.

critically endangered

level of conservation between "endangered" and "extinct in the wild."


structure built across a river or other waterway to control the flow of water.

Emerging Explorer

an adventurer, scientist, innovator, or storyteller recognized by National Geographic for their visionary work while still early in their careers.


no longer existing.


to harvest aquatic life to the point where species become rare in the area.


to make, or cause to become.