Editor's Note: For this month's feature story, "What It Takes '05: Hard Science," we took a look at ten courageous field scientsts who risk everything to turn in their data. Imagine facing Monday morning deep inside a melting glacier or chasing polar bears, or parachuting into a jungle that no one's explored. Biolgist Zeb Hogan, featured here, is also a National Geographioc Emerging Emplorer.

Online Exclusive: Hear Zeb Hogan reveal what it takes to get to know the giant freshwater fish of the Mekong River on National Geographic's World Talk >>

As head of Cambodia's Mekong Fish Conservation Project, Zeb Hogan has saved dozens of giant freshwater fish from local nets. This year the World Wildlife Fund and the National Geographic Society sent him on a two-year, six-continent mission to identify and study any freshwater variety over six feet long or 200 pounds.

''I don't have a party lifestyle in Phnom Penh, where I live, so when my cell phone rings at 2 a.m., I know it's a fisherman. They all have my number. On the market, they get 50 cents a kilo for a giant catfish. I pay a dollar. My Khmer isn't good, but I can understand someone yelling, 'Big fish, big fish! Come now!'


"The river is about half an hour away, and I'm usually riding in the rain, in the dark, on the back of a motorcycle. We pull up to some shantytown fish market where everyone's shouting and haggling and a boat appears to take us to the nets.


"The first year, we had one that weighed 595 pounds. Bugs were swarming around my headlamp, and someone pulled on a rope and this huge fish came up out of the murk. To lift it up and weigh it, we wrapped it in a plastic tarp and put five guys on each side. The most important job is holding the tail. That's where the fish gets its leverage. If you let go of the tail, that's it.


"When we released the fish, it nearly sank us. Now we use bigger boats, but that night it was a 12-foot boat dragging a ten-foot fish. We inched along, killed the engine, and I jumped in. Giant catfish grow weak after fighting a net, and I have to grab on to them to make sure they're strong enough to swim before we release them. I hold on to the mouth, on to one of their big lips. I get its head down, so water can move through its gills. After a while, a catfish regains its strength and dives deep, where it's safe, and where I can't go."

Read about the nine other amazing field researchers in the October 2005 issue of Adventure.

Volunteer Research Vacations: Play field researcher on one of these ten scientific expeditions around the globe >>


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