The endangered Mekong catfish can be as big as a grizzly bear. A Mekong giant catfish was recently caught and released.
National Geographic explorer Zeb Hogan (pictured, left) helped Cambodian fisheries officials mark and release a rare Mekong catfish that fishermen caught near Phnom Penh on Nov. 9.
Courtesy photo: University of Nevada, RENO
Written by: Brian Clark Howard, National Geographic
A group of Cambodian fishermen harvested a big surprise earlier this month: a large Mekong giant catfish, which was seen in the country for the first time this year.
Zeb Hogan, a fish biologist at the University of Nevada, said the giant catfish was captured near Phnom Penh and is about 2.1 meters long and weighs about 90 to 114 kilograms. Reno checked and marked the fish.
"It's not too big for the Mekong catfish, but it's still bigger than any catfish caught in North America over the past century," Hogan said. He is a National Geographic explorer and host of The River Monster on the National Geographic Wildlife Channel.
The largest known catfish in North America is the blue catfish caught in North Carolina in 2011 and weighs about 65 kilograms. But compared to the grizzly bear-sized Giant Catfish caught in Thailand in 2005, it weighs about 293 kilograms and is about 2.7 meters long.
As their name suggests, the Mekong catfish live in the Mekong River basin of Southeast Asia. They are the largest scaleless freshwater fish in the world, and are also known in the region as "royal fish" due to their size and importance to the local culture.
"This catch is exciting because it means that this extremely rare and endangered fish still lives in the Mekong and still migrates from Tonle Sap Lake to the Mekong River every year to spawn," Hogan said.
In the 19th century, thousands of Mekong catfish were captured each year. But their numbers have plummeted by 95 percent due to overfishing, pollution and habitat destruction. Today, no more than six Mekong catfish are found each year within their habitat.
Killing the catfish is illegal locally, but a series of new dams on the Mekong could wreak havoc on the catfish's habitat.
"If their spawning grounds were upstream of the dam, they might be cornered," says Hogan, who has been studying the fish for 20 years. "But we don't know anything about it."
To better understand the fish's behavior, Hogan and officials from Cambodia's Fisheries Ministry put a plastic label on the catfish's fins. If it can be seen again, the research team can learn more about its actions. This fish lives for more than 60 years, so it can provide us with important data for a long time.
This large fish is about 2.1 meters long and weighs about 90 to 114 kilograms.
In order to release this "giant beast", Hogan dived into the water about 3 meters deep. It quickly wandered on its own, and its body looked healthy. When fishermen first caught it, they sprayed it with perfume, a cultural symbol of respect.
(Translator: King of Hearts)