Exploring the largest swathe of protected rainforest in South America

Saro grabbed my arm and pointed into the flooded forest where the creek spread mirror-calm through endless trunks into darkness.

“Shhh!” he said, cutting the boat engine. We stopped talking and drifted slowly, like a fallen petal on the current. With the outboard silent, I noticed that the forest was alive with sound – the whirr of cicadas, the chic-chic of kingfishers, the chirrup of frogs. A pair of metre-long blue-and-yellow macaws flew over us, screeching raucously.

But I still couldn’t see what he was pointing at. I shielded my eyes from the sun and squinted into the gloom of the flooded forest. Handkerchief-sized, electric-blue morpho butterflies floated between the trees. A purple gallinule – like a giant, regal moorhen – waded over a bed of water hyacinth on spindly yellow legs. Then I saw a flicker; an undulation of something man-sized, swimming between the trunks. Then a sheen of wet, waxy fur flashed out of the water, illuminated in a shaft of light that pierced the canopy. There was a snort, followed by the sound of rapid breathing. Whatever it was, it was coming closer.

“Ariranha!” whispered Saro.

Now it was right by us. Something broke the creek’s surface a few metres in front of our prow: inquisitive, dark eyes; a sleek brow; and a face that came clear of the river, beady eyes staring right at us, with a dab of white under a big whiskered mouth filled with sharp teeth. I gasped.

“Ariranha!” repeated Saro softly, “A mother giant otter! She will call her cubs to come close. Watch!”

The mother let out a rasping cry, then three smaller faces bobbed behind her. They stared, inspected us from afar, as curious as cats, as cute as puppies – though each was as long as an adult labrador. Their mother cooed, played with her cubs and then suddenly remembered herself and barked sharply. An alarm warning. “Not food,” she seemed to call, “but danger!” Just as quickly as the family had appeared, they vanished, beneath the water and back into the trees.

I pinched myself. A giant otter in the wild! After decades of hunting, these spectacular animals have been pushed to the brink of extinction. To see one outside of a wildlife documentary was nothing short of extraordinary. To see a whole family filled me with hope. It was a sign not only that we were in the depths of the Amazon’s wilderness, but that, despite the ravages of Brazil’s Bolsonaro government, there…