Two boys lug weighty river catfish in Cambodia. Once a staple food in Cambodia, catches of these large, slow-maturing fish have dropped 90 percent in the past 20 years.
Photograph courtesy Zeb Hogan
Map
Fast Facts
- Type:
- Fish
- Diet:
- Omnivore
- Average life span in the wild:
- Unknown
- Size:
- 5 ft (1.5 m)
- Weight:
- Up to 99 lbs (45 kg)
- Did you know?
- One in every four freshwater fish, and one in every ten of the world's fish, is a catfish.
- Size relative to a 6-ft (2-m) man:
-
The river catfish may be overshadowed by its famed cousin, the Mekong giant catfish, which shares the same river system in Southeast Asia. But this less celebrated species is a remarkable fish in its own right and, at 5 feet (1.5 meters) and 99 pounds (45 kilograms), it has no apologies to make in the size department.
River catfish are known to inhabit Tonle Sap Lake in Cambodia. Every year they leave the lake and enter the Mekong River as part of their annual spawning cycle. Breeding begins at the onset of the region's rainy season (May-July).
These unique fish have the nickname "iridescent shark catfish," a seemingly ill-suited comparison for a toothless, freshwater fish. The nickname arises from its tendency to swim close to the surface, raising its dorsal fin above the water. As for iridescence, river catfish have no scales, but their delicate skin is covered with a protective layer of slime that gives them a shiny glow.
These fish are threatened with habitat fragmentation, industrial pollution, and overfishing. Many millions of people depend on the Mekong River for sustenance, and river catfish have long been targeted for their succulent meat.
They are extensively farmed along some sections of the river, such as in Thailand, where wild specimens have become quite rare.
National Geographic Emerging Explorer Zeb Hogan is attempting to learn more about these catfish by conducting a large-scale tagging and monitoring study. Since 2004, his team has tagged more than 3,000 river catfish in hopes of documenting their behavior and helping authorities to provide better protections.
Photo Galleries
Freshwater Heroes
Environment Photos
Why Care About Water?
The National Geographic Society’s freshwater initiative is a multiyear global effort to inspire and empower individuals and communities to conserve freshwater and the extraordinary diversity of life that rivers, lakes, and wetlands sustain.
Freshwater Advocates
-
Sandra Postel
Sandra is a leading authority on international freshwater issues and is spearheading our global freshwater initiative.
-
Shannon Switzer
Shannon Switzer is an inspring young photographer and conservationist.
-
Zeb Hogan
Zeb travels to the most endangered freshwater ecosystems striving to save critically endangered fish.
Advertisement
Water Currents, by Sandra Postel and Others
-
What is Your Water Footprint?
Find out with our footprint calculator, then pledge to cut it!
-
The Hidden Water We Use
Find out how much water it really takes to support your lifestyle.
-
Take Action
Help lower your global water footprint and conserve water. Learn what you can do to help.
Special Ad Section
The World's Water
-
Why Should You Care?
Learn more about the world's water challenge with photos, stories, videos, and more.
-
Visualizing Our Water Footprint
You might be surprised to see how the daily choices you make affect critical watersheds around the world.
Test Your Water IQ
-
Photos: In the Field
Browse breathtaking images of life on the Serengeti.
-
A Thing or Two About Twins
Can the unique bond between identical twins be explained?
