In the summer of 2022, a group of scientists and conservationists traveled to the Alto Mayo region of northern Peru.
For 38 days, Trond Larsen, an ecologist at Conservation International led a team of 12 Peruvian scientists with the help of expert guides from the local indigenous tribe, the Awajún. Over the course of the trip, they found 27 species previously unknown science.
These findings were surprising because the expedition was in an area dominated by people and actively being deforested due to pineapples, rice, coffee and chocolate agriculture.
Hiding in plain sight
On the first night of the expedition, Larsen finished his dinner quickly and walked out with a headlamp, excited for what he might see.
Within just a few minutes he noticed something that shocked him: "I'm looking in the vegetation and just about chest height is this small bronze, beautiful salamander on a leaf with stubby little legs and, you know, a stubby tail, robust, chunky tail."
Larsen says salamanders are rare in the tropics – and this one is so rare, it's new to science! The Bolitoglossa salamander was thriving but only in a small patch of white sand forest.
That wasn't the only shock of the trip.
By the end, Larsen and the team documented 2046 species, 27 of which had never been recorded by scientists.
"Finding so many species of vertebrate animals, of mammals, four new species of mammals, that's almost unheard of on an expedition like this," says Larsen.
A swimming mouse particularly captured the hearts of the team. This newly-described species is part of a larger group of rare semi-aquatic rodents. It has partially webbed toes and lives a lot of its life underwater, swimming and hunting aquatic insects.
Rounding out the list of mammals was a squirrel, a bat and a spiny mouse.
Then, there were the fish – specifically, eight newly described species. Arguably one of the most photogenic among them: the blob-headed catfish.
But this fish was not new to everyone.
New to whom?
The fish is used in traditional dishes eaten by the Awajún, a local Indigenous tribe. So, it was funny to Yulisa Tiwi, an Awajún woman on the expedition team, that it was new to science.
"When a scientist comes and tells us that this is something new for the scientific community, we just say 'Wow!' And it's like ... 'That's different.' Let's take a look at all the other species we have," she says.
What did surprise Tiwi was finding a critter that she thought had disappeared from the forests in the Alto Mayo.
When Tiwi was young, her grandparents regaled her with stories of their warrior ancestors. Her grandparents would recount tales of a frog's poison used to coat the tips of weapons. So when the Atelopus frog was found, she was overjoyed.
"After everything that I had been told by my grandfather, being able to see that species, to know that it's still there – was a bit thrilling. Being able to say, 'Wow, this species still exists; we can extract its venom to kill whoever we want,'" she laughed.
Tiwi hopes that future researchers working in Peru will learn from the collaborative nature of the expedition – and specifically seek out the expertise of the Awajún women. "Women are the ones who possess more traditional knowledge. They have a deep knowledge of their territory, of their forest," she notes. "They know about food, about medicinal and edible plants, how to move around during the night and guide you on a hike."
Larsen echoed this feeling, and particularly emphasized how additive the partnership was for their species documentation. "To find so many new species living in these human dominated landscapes. But I think, you know, in large part, it's due to the hard work that the Awajún people have put into protecting their indigenous lands and the forests and the biodiversity that they depend upon."
Given that scientists hadn't expected to find so many new species here, right under people's noses, it makes you wonder: What else is lurking right in front of us?
Other ecosystems or critters you think would make a good episode? Let us know by emailing shortwave@npr.org!
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This episode was produced by Hannah Chinn. It was edited by our showrunner, Rebecca Ramirez. The audio engineer was Jimmy Keeley.
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