"Discovering even one new species of mammal on an expedition would be extraordinary, but discovering four new mammal species, as well as eight new fishes and three new amphibians, is mind-blowing," said Trond Larsen, leader of the Rapid Assessment Program at Conservation International, as Euronews reported.
The expedition was led by a team of researchers from Conservation International who were joined by Indigenous scientists and guides from Global Earth, as well as local experts from the Indigenous Regional Federation of the Alto Mayo Awajun Communities.
"We know very little about the planet's biodiversity, and these ecosystems hold so many mysteries," said biologist Wily Palomino with Conservation International, who was part of the expedition, in a press release from Conservation International. "It would take 10 lifetimes to truly understand them. Expeditions like this are just the beginning."
The Alto Mayo is a diverse and complex landscape of intertwined ecosystems and local communities that stretches from the Andes mountains to the Amazon.
The purpose of the expedition was to find the greatest number of species in a short time. The setting for this unique search was unusual, however, since the area has been scarred by deforestation and is full of human settlements, rather than being the kind of "pristine" forest setting where an abundance of rare wildlife would be found.
The researchers said the findings of the expedition demonstrate that people and nature can live side by side, but we must take immediate action to preserve it.
During the expedition, the team of 20 slogged through swamps, rivers and lagoons. They crossed farm fields and climbed mountains into cloud forests, all the while looking for movements and other signs of animals while setting up camera traps and collecting samples.
Of the 2,000 species they recorded, 27 were new to science and nearly 50 are threatened with extinction. Four of the newly discovered species were mammals.
"Mammals are the best-known animal group in the world -- so discovering four new mammals in any expedition is surprising," Larsen said in the press release. "Finding them in a region with significant human populations is extraordinary."
The amphibious mouse the team discovered is part of the aguajales ecosystem -- a swampy area dominated by aguaje palms. The area is a designated "ecosystem recovery zone," where deforestation for rice farming is a threat to the mouse's unique habitat.
Larsen said the species -- which likely exclusively inhabits the Alto Mayo -- is part of a semi-aquatic group of rodents, of which most known species are exceptionally rare.
Just before coming upon a dark brown harlequin frog -- Atelopus seminiferus -- an extremely rare species that had never been seen at such low elevations, "Larsen had crossed a muddy logging track, where a donkey pulled a cart of fresh-cut timber through the forest," the press release said.
Palomino said many researchers hypothesize that fragmented forested areas hold little biodiversity, which is why they have largely ignored places like Alto Mayo. Palomino said the expedition challenges those views.
"The discovery of so many new and threatened species was so surprising, in part, because it was a nearly blank slate -- no one has ever really looked," Palomino said in the press release. "Now, we're proving the unexpected: Small patches of healthy forests can support a wealth of species."
Approximately 280,000 people live in Alto Mayo, including Indigenous Awajún people. To make ends meet during the end of the 1990s and early 2000s, community members were forced to allow migrant farmers to rent their lands.
This led to a steep rise in deforestation, according to Diego Dourojeanni, Conservation International's leader of work with Alto Mayo's Indigenous Peoples.
"Communities didn't deforest their land because they wanted to -- it was out of necessity," Dourojeanni said in the press release. "While it helped in the short term, it became clear that this practice came at a steep cost to resources, food security and the ecosystem services like clean water that the forests provide."
The expedition came out of efforts to address deforestation by working with the Awajún people and other local communities to help build alternative sources of livelihood, like selling vanilla and medicinal teas, in addition to practicing agroforestry with coffee beans and cocoa. They are also striving to improve Awajún community governance to ensure sustainable and equitable management of their territory.
The expedition was the beginning of a plan to connect Alto Mayo's remaining patches of abundant biodiversity to create a conservation corridor for the long-term protection of the region's wildlife.
"To effectively protect nature, you first need to know what's there," Dourojeanni explained. "By understanding where wildlife lives, we can make better land management decisions and target areas that are best suited for conservation and sustainable activities like ecotourism, selective logging and sustainable agriculture."
Dourojeanni said getting a better idea of what lives in the forest is not just important for economic reasons.
"We want people to value forests and resources in a more emotional way," Dourojeanni emphasized. "Because the truth is that if it's just for income's sake, it's really, really hard to compete with agricultural drivers of deforestation. And traditional knowledge on how to use the forest is at risk of being lost in a generation or two."
Dourojeanni said there have been signs of progress in the last decade. Communities have stopped renting out their land as much and have a better understanding of how important it is to protect their forests.
"It's not too late yet," Dourojeanni said. "If we do the right thing, people and nature can co-exist on this landscape."