New videos reveal the hidden lives of Andean bears

Camera collar footage is unveiling the secret lives of Andean bears (Tremarctos ornatus), South America’s only surviving ursid. A wild Andean bear in Peru was caught eating soil or clay, courting females and even cannibalizing a dead bear cub.

“It’s so hard to see an Andean bear,” says Ruthmery Pillco Huarcaya, a wildlife biologist at Amazon Conservation, a nongovernmental organization in Cusco, Peru. Scientists estimate there are fewer than 20,000 left in the wild. “And it’s even harder to see what they are doing.” Even though the bears are deep brown or black with bright spectacled faces and can weigh up to 340 pounds, they’re tricky to spot in the dense, steep forests of the Andes.

Zoos and sanctuaries offer some insight into the bears’ mannerisms but not much. It’s their behavior in the wild that is crucial for informing conservation decisions. The Andean bear is listed as vulnerable on the International Union for Conservation of Nature red list, and the species is under threat from illegal poaching, habitat loss, mining and climate change (SN: 4/30/24). Now, collars equipped with video cameras are offering up some clues into the bear’s natural behavior, researchers report December 4 in Ecology and Evolution.

The project “is wonderful, and it’s unique,” says Mauricio Vela-Vargas, a wildlife biologist at the Wildlife Conservation Society in Bogotá, Columbia, who wasn’t involved in the research. “For the first time, we have information that affirms a lot of hypotheses.”

Bears have long been embedded in Andean folklore. In a Quechua village by Cusco, Pillco grew up listening to her grandmother’s stories about ukukus — half human, half bear demigods who climbed a Peruvian glacier to bring water back to nearby human communities. She always wanted to discover more about the real bears, the real ukukus, living nearby.

Pillco now leads the initiative to attach camera collars to Andean bears across Peru’s Kosñipata Valley. Sitting back and looking through videos may seem straightforward, but watching the footage is just the tip of the iceberg. Before they could comb through the footage, Pillco’s team had to find bears, catch them and attach the collars.

The task wasn’t easy. The valley’s terrain is rugged and inhospitable to hikers, says Andrew Whitworth, an ecologist specializing in tropical biodiversity at Osa Conservation, a nonprofit in Costa Rica. He had never seen an Andean bear before. Whitworth says he joined Pillco on the project, intrigued by “the excitement of doing something that’s really difficult and a little bit insane.”

To catch the bears, Pillco asked a local mechanic to help build traps — huge metal boxes designed to capture Andean bears and ping the researcher’s phones. 

“Sometimes we had false alarms, but the first time was a full experience,” Pillco says. 

One night, they had sent a field assistant on a lengthy hike through the rugged forest to bait a trap near where they suspected a bear was wandering. On the assistant’s way back, the entire research team’s phones started pinging ‘TRAP ALERT’. Pillco was convinced the assistant had done something wrong. She grilled him: “Did you close the door?” Did you set it properly?” The assistant assured her that everything was done right. Still, she asked him to go and check. 

“He went back, and the bear was there! … It was just waiting for the bait to be put in,” she says. Whitmore, who was almost too sick to move at the time, was so thrilled he got out of bed and was among the first to arrive at the scene.

Pillco and Whitmore initially tried out Crittercams, small GoPro–like cameras that hook onto separate collars, on two bears they were able to catch. They were eventually able to hook up another bear with a camera collar — a different device that integrates video, GPS location and movement speed. 

This bear wore the camera collar for four months. Then, the researchers had to retrieve the device.

“That was one of the toughest things,” Whitmore says. The team could release the collar remotely. But it didn’t fall off right away. Once they had a general location, the team, which included locals who knew the terrain, backpacked out to retrieve it. They ventured through the thick cloud forests, crossed a river by building their own bridge and walked for days until they reached the right area. Everyone combed the ground — including Pillco’s search dog Ukuku. But it was a local guide who found it first.

The collar footage revealed Andean bear behavior never recorded before. The bear consumed previously undocumented foods like a type of stinging nettle plant, a wooly monkey and a dead bear cub, and he spent seven days mating with a female bear (with breaks, of course). And even though Andean bears are thought to be quite isolated creatures, this one bear encountered others, usually peacefully, many times. 

The footage is important not only for scientists but also the local communities, which own much of the land where Andean bears live. As people in those communities try to conserve swaths of land, knowing what kind of berries and plants Andean bears like to nibble on helps land managers decide what species to grow. Pillco is also presenting her videos at an upcoming bear festival and working with nearby schools to engage children with the forests and bears that surround them.

“We’re really looking to build conservation ambassadors with community people, because I think it’s key to empower them” to protect their land, Pillco says. “Because I can go, my organization can go, but the communities are going to stay there.”