Searching for Pink Dolphins in Bolivia's Amazon

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.

Photo: Searching for Pink Dolphins in Bolivias Amazon: When A Story in An Obscure Corner of the World Doesnt Turn Out Quite as PlannedPlay

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.

Photo credit: ABC News/Jeffrey Kofman.

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."

Development Poses Threat to Wildlife

As we cruised up river, we spotted spectacular jungle birds, beautiful butterflies and colorful trees and flowers. But dolphins?

In unison, Tavera and our boat driver pointed to a distant spot ahead. All we saw was a pool of water, as if someone had thrown a rock into the water. Then another. Then another. Clearly there was some creature ahead, but it grazed the surface so briefly that there was no way to see it. A dolphin? Maybe. Pink? Maybe.

We had come to see the dolphins because, in this part of the Amazon, they are considered a barometer of the river's health. Bolivia's poverty and remoteness have left this corner of the Amazon undeveloped and relatively untarnished. But that isn't going to last much longer.

Remote places like Bella Vista get their electric power from diesel generators, which operate a few hours each day when the diesel barges can maneuver up river. Bolivia's government is under enormous pressure to harness the power of the river's rapids to create a perpetual and cheap energy supply.

Those are small projects, but across the border, the Brazilian government is building two massive dams to provide electric power for that country's exploding economy. Although they hold promise for clean energy, the dams have an unforeseen cost: flooding huge areas.

The new lakes threaten to alter one of the most pristine tropical wildernesses on the planet. Scientists believe that thousands of years ago, dolphins from the ocean swam up the Amazon's tributaries and become isolated here by the huge rapids that mark the rivers' rapid descent. The dams threaten to flood the rapids and, with them, the isolation that allowed the pink dolphins to evolve.

The dolphins here are seen as the proverbial canary in the coal mine: If they are healthy, the other creatures in the river are healthy, too.

"It can provide a sense of how the water and forest are doing, how the whole system is doing because they feed on fish, who have eaten fish, who have eaten other fish," said Marianana Panuncio, a field worker at the World Wildlife Fund's Bolivia office. "So if there is something wrong with the system, in a way the dolphin acts a warning bell for the health of the river."

Pregnant Women: Dolphin Seduction?

Back on the river, we'd spent a day-and-a-half looking for dolphins. It was an exercise in exasperation. We saw flashes of pink -- not a bright pink, a fleshy pink -- like the skin of the very pink pigs we saw ambling up Bella Vista's streets.

But try capturing these elusive creatures on camera. It was as if they were taunting our trusty cameraman, Al Durruthy. The crafty dolphins seemed to be laughing at Al as they surfaced everywhere his camera wasn't.

"Damn, they're fast," said Al, with a sense of defeat in his voice.

Time was running out. Our boat driver had an inspiration. After a lunch break, he returned with a guest -- a young woman from the village. Her name was Dorca, she was 21 years old and very pregnant.

"Yes," Dorca said, "I believe I can help you."

According to local legend, a protective instinct in the dolphins attracts them to pregnant women. And, so, there we were, quietly motoring up river with a very pregnant woman at my side in the boat -- a strange form of dolphin seduction. Now, it really felt like the dolphins were laughing at us.

Alas, Dorca didn't seem to make much difference. Yes, we spotted the fleshy pink of a few dolphins as they surfaced -- oh-so-briefly -- for air.

Yes, they are pink. And yes, they are abundant. Catch a glimpse of them ... if you can.