Field Notes: Whitewater and Monster Fish on Brazil’s “River of Doubt”


I’m in Cacoal, Brazil, with National Geographic explorers Zeb Hogan (left), the world's foremost megafish expert, and Trip Jennings (right), an accomplished kayaker and filmmaker. Located 130 miles east of the Bolivian border, the town is just a few hours' drive from the where we’ll launch the first-ever expedition to study the aquatic life in the Rio Roosevelt, once known as the River of Doubt, tomorrow morning. If we're lucky, we'll get to document some of the huge fish Teddy Roosevelt described during his 1914 exploration.

—Text by Kyle Dickman; Photograph by Adams Mills Elliott

It just so happens that Cacoal is celebrating its 90-some-odd-year anniversary with too much sugarcane liquor. This occasion would normally merit grabbing a Cachaça and lime and hitting the streets to dance, but the only thing open in this jungle-frontier-turn-cattle town is the bars. The problem? We’re still trying to source gear we’ll need for our 130-mile float down the Rio Roosevelt’s whitewater. As I write this, my teammates are looking for the propane we'll need to cook during the trip.

Our eight-person crew has been in Brazil for three days now. The highlight so far was a 3 a.m. stop (that’s when it opens) at one of Brazil’s largest fish markets in the Amazon-riverside city of Manaus. This is where Zeb Hogan, a 35-year-old icthyologist, went to work. In two hours, he identified a handful of the 300 species of freshwater fish sold at the floating market throughout the year.

Hogan’s been globetrotting since he founded the Megafishes Project in 2006. His goal is to catch and document as many of the world’s two-dozen species of freshwater fish that grow larger than six feet as he can. Two-thirds of the giants are already listed as endangered or threatened. Our Brazil project’s different than the 40 other Megafish Projects Hogan's led. Not only is he rafting, which is new to him, but scientifically Hogan’s not sure what he’ll find during the ten-day research expedition. But then again, nobody is. The three other expeditions who traveled the length of the river, most notably President Theodore Roosevelt’s 1914 first descent that gave the river its name, researched and cataloged terrestrial species—insects, birds, mammals—while navigating the Class III-IV rapids studding the river. Hogan will be the first to focus on the Roosevelt’s aquatic life mostly because he’s teaming up with whitewater-expert Jennings to access the habitat. Come tomorrow morning, assuming we score a propane tank, we’ll see how these two explorers' collaboration works out. 

See their Spot Satellite Messenger posts here or follow the team on Twitter.

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