Dramatic underwater photos capture the elusive Amazonian pink dolphins red-handed.

In 2023, as the Sun was about to set, photographer Thomas Peschak entered the black waters of the Rio Negro River in the Brazilian Amazon. With his camera in hand, he waited for the perfect moment to catch a thief in the act. As fishermen cast their nets into the river, suddenly a sleek pink shape emerged from the depths, swimming toward the trapped fish. Peschak held his breath underwater and started shooting. Moving quickly, the creature – an Amazonian pink river dolphin – poked holes in the net and stole a catfish.

"They are very agile and can manoeuvre with incredible exquisiteness around these nets underwater," Peschak says. "They are great thieves!"

At the time, Peschak knew he was documenting something no one else had managed to capture on camera. These dolphins have learned to associate the nets and the sounds of fishing boats with an easy meal. Peschak is the first photographer to document this behaviour underwater.

The lack of precise information on where to find these animals and the poor visibility in the muddy waters of the Amazonian rivers were major challenges, he says. But Peschak, who has worked as a marine photographer for over 20 years, drew on his expertise in ocean documentation. "In most of these rivers in the Amazon, no one has ever dived to photograph before," he says. "There's no map, no description. You basically have to go underwater and figure things out for yourself."

Untold Amazon

As global leaders gather in the Brazilian Amazon city of Belém for COP, the UN Climate Change Conference, we are running a special series exploring this iconic region's mysteries across different countries.

The photos earned him the photojournalist story award at the prestigious Wildlife Photographer of the Year Award in 2024.

Known locally as boto in Portuguese and bufeo in Spanish, the pink river dolphin is a funny sight. With its melon-shaped head, rose-coloured skin, and slender, hundred-toothed snout, it is the largest freshwater dolphin in the world, growing up to 2.5m (8.2ft) long and weighing as much as 200kg (440lbs). Four types of pink river dolphins live in the Amazon River basin. All of them are endangered, facing significant population declines in recent decades due to hunting, entanglement in fishing nets, pollution and droughts.

Like other dolphin species, they use echolocation to "see" by emitting clicks and interpreting the returning echoes. But the bump on top of their foreheads, called a "melon", serves as an extra aid in navigating their murky environment, functioning as an amplifier for sound and helping them create a mental map of the water, its obstacles and prey.

The dolphins' unusual body shape, skills and intelligence have contributed to rich folklore about them. Many indigenous groups and river communities throughout the Amazon rainforest share stories of the boto living in an underwater world with vast cities deep inside the rivers. Other tales, less sympathetic towards the animal, claim that the dolphins can transform into humans. At night, they appear in villages disguised as pale men who seduce and kidnap young women.

The reputation of a thief, whether of women or fish, has made life difficult for the pink river dolphin, according to Peschak. While revered and........

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