A “Swat ecological team” has discovered 20 hitherto unknown species in the misty cloud forests and cascading waterfalls that flank the Zongo Valley in Bolivia.
Among the animals found were a tiny 10mm long frog, a viper, two metal-branded butterflies and an orchid with a viper’s mouth. The virgin forests are just 48 kilometers from the capital, La Paz, but the expedition also rediscovered the devil-eyed frog, seen once before, and a satirical butterfly that had not been seen for nearly a century. Next to these were endangered species, including the bear with glasses and the toucan with the beak of a canal.
The high and coastal peaks of the Andes are home to enormous biodiversity because movement between them is difficult for wildlife and gives rise to isolated points of evolution known as “islands of the sky”.
The scientists spent two weeks walking up and down the 2,000-meter slopes and, while hoping to find new insects, were surprised by what they found. “We certainly didn’t expect to find new vertebrates, like the two snakes and the frog, so it was very exciting,” said Trond Larsen of Conservation International, who co-led the expedition with Claudia Cortez, head of conservation of the municipal government of La Paz.
Brachionidium, or cup orchid, with striking purple and yellow flowers. Photography: Trond Larsen / Conservation International
“What’s so amazing is that you could hear the distinctive frog trick all over the woods, but you come over and stop calling,” Trond said. “Trying to detect it when it doesn’t make any sound and it’s hidden in the moss was a tremendous task.”
The team rediscovered the devil-eyed frog that had only been seen once, 20 years earlier, by Steffen Reichle, a Bolivian-based scientist who was also involved in the new expedition. “It was really exciting: it was supposed to be extinct, but we actually found it to be relatively common,” Larsen said.
The expedition was part of Conservation International’s Rapid Assessment Program, which Trond describes as an “ecological SWAT team” that responds when information about a little-known area is urgently needed.
In the Zongo Valley, the assessment supports a new conservation area that will protect not only wildlife but also clean water, building materials and forest food on which locals are based. The ecosystem also regulates the flow of water to the small dams in the valley that help feed the capital of Bolivia. Protected mountain slopes will also provide vital refuges for species moving upwards to escape the growing heat caused by the climate crisis.
Oreobates zongoensis) was previously known to only one individual observed more than 20 years ago in the Zongo Valley. Photography: Steffen Reichle / Conservation International
The team of scientists, made up of 17 people, entered their study area by a long, high suspension bridge that stretches across the Zongo River. In addition to the highly poisonous shortener, they found another new snake that had the colors red, yellow, and green of the Bolivian flag.
The flowers of the new viper-mouthed orchid appear to mimic an insect and can be used to trick involuntary pollinators, while a new cup orchid showed striking purple and yellow flowers.
A species of bamboo found by the team was new to science, but already well known to indigenous communities who use it to make musical instruments. sikus, or panpipes. Another plant, from the root family, which closes the leaves at night, resembling hands in prayer, was rediscovered after 125 years.
“This truly beautiful and diverse landscape has become a safe haven for amphibians, reptiles, butterflies and plants that have not been found anywhere else on earth,” Larsen said.