It was about as exotic as an assignment gets: a journey to the Amazon Basin in search of the elusive pink dolphin, now under threat by development.
Our adventure began long before we arrived in the Amazon. There was the overnight flight to La Paz, Bolivia's capital high in the Andes mountains. Then there was a sunrise flight to the tropical city of Trinidad, capital of Bolivia's Amazon. Finally, there was a charter flight into the jungle aboard a flashy single-engine Cessna with a colorful -- and aggressive -- eagle painted on its front.
As we left civilization behind, I looked down on the open grasslands of the savannah below as hardy cows grazed freely. The savannah gave way to a lush landscape of swamps and dense jungle. Although the sun was shining, we could see isolated clouds on the horizon, with rain falling below -- as if in a child's drawing of a rain cloud. And just as you'd expect in that drawing, the sky was framed by a spectacular rainbow.
As I marveled at the scenery, my thoughts drifted to the assignment ahead. Suddenly, I found myself drifting back to another exotic adventure I'd taken in 2008. I traveled to Patagonia in Southern Chile to look at a fascinating and unknown population of blue whales in the Gulf of Corcovado.
In the spectacular setting, we delighted as our boat was escorted by a dozen deep-sea dolphins. What a thrill it was to see their gray-blue bodies bound through the air all around us. Would we really witness this again in a river setting with dolphins that were pink?
No time for nostalgia, our destination was below: the remote village of Bella Vista on the Rio Blanco, a tributary of the Amazon. This village of 1,500 people is a 36-hour bus and barge ride from Trinidad -- when the road is passable.
It is a poor place, but the wealth of fish, game and tropical fruits means the people here live a life of rugged abundance. After we settled into our jungle lodge, we boarded two long, narrow wooden boats. With cameras rolling, we slowly motored our way up river.
My guide was Gabriela Tavera, a biologist with the Bolivian nature group Faunagua who has been studying the mysterious dolphins for the past three years. We quickly learned that there are actually two species of dolphins in the Amazon: Bolivian pink dolphins and traditional river dolphins.
"It's easy to recognize where they [the Bolivian dolphins] are because when you see the water, and it's really calm," Tavera said. "It's easy to see the waves they make when they're swimming and catching fishes and playing, so you notice them when you see them."
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Easy to see them? As we motored our way up the river, we scanned the river's surface and saw nothing. I had a sinking feeling.
Our trusty boat driver, a local villager, began pounding the water with his paddle, assuring us that far from being skittish, the dolphins are attracted to noise.
Tavera encouraged us to keep looking for a break in the water's surface or a splash.
"Here in Bolivia, we have one of the healthiest populations of river dolphins in the world," she said with confidence. "You can easily find them. You can see them. They are really playful, and curious, so they're really a great species to see."