Guardian of the Cotton-top

The landscape architect who became the unlikely steward of Colombia’s critically endangered one-pound monkey

Rosamira Guillen’s first job back in Colombia wasn’t very glamorous. In 1995, fresh off a prestigious Fulbright Scholarship to study landscape architecture in the United States, she returned home to Barranquilla, a port city on the country’s northern coast, to work in a zoo. But the task of remodeling a small, putrid lagoon had Guillen swiftly lamenting the zoo’s deteriorating condition. “It was a zoo of the ’60s, with iron cages that looked like jails,” she recalls.

One of those enclosures housed a colony of small monkeys with dark, leathery faces and a puffy white mane. For Guillen, the squirrel-sized creatures, called cotton-top tamarins (Saguinus oedipus), were a respite from the otherwise dreary zoo. Their raucous chatter, jittery energy, and Einstein-like heads of hair captivated her. She was surprised to learn that the tamarins were native to her country, and in fact were found in the wild only in a few forested patches of land, near the Caribbean coast of northwestern Colombia. Not only were the tamarins rare, they exhibited unique behaviors, including a complex language that contained close to 40 distinct chirps, squeals, and whistles that the monkeys delivered in grammatical sequences—almost like sentences. And unlike most other primates, tamarins displayed an altruistic streak, raising their young in groups, rather than leaving each mother to fend for her own young. For such a small monkey, Guillen thought, they had huge hearts.

Though Barranquilla, Guillen’s hometown, was just a short drive from the forests that echoed with the monkeys’ bird-like whistles and chirps, she had never heard of this tiny primate, nor how rare it was. “I grew up and was born here, and they never taught me any of this!” she says. “I thought that was terrible.”

Over the next few years, that initial astonishment grew into a consuming fascination. Guillen devoured all the literature she could find on the tamarins—or titís (pronounced tee-TEES), as they’re called in Colombia. She learned that the species was endangered and that the titís were fast losing their forest home. And yet most Colombians didn’t know the monkey was anything special. The local costeños—coastal folk—didn’t know that cutting down the forests for charcoal, fence posts, and pasture was, tree-by-tree and acre-by-acre, backing the tamarins into a corner, eliminating the very habitat they required.

When Guillen was named director of the Barranquilla Zoo in 2001, she made the little monkey its emblem and embarked on a mission to conserve the cotton-top tamarins’ remaining forest—and to educate Colombians about just how special the titís are.

But she knew changes at the zoo wouldn’t be enough. Securing the titís’ survival would depend on turning the monkeys’ human neighbors into allies. To truly help the monkeys, she had to meet them—and the costeños—out in the wild. In speaking with people who lived on the fringes of the tamarins’ habitat, she says, she stressed that the titís’ conservation, by preserving forests and natural resources like water, would benefit both the monkeys and Colombians. It would be a win-win, she told them. Like many conservation projects, says Guillen, keeping the needs of humans is paramount. “We don’t want to tip the balance only for the titís and the forest, because you can’t leave the human component out.”

Today, Guillen is one of the cotton-top tamarins’ most vocal guardians. In 2008, she was hired to run Proyecto Tití, a non-profit based in Barranquilla that’s dedicated to protecting the cotton-top tamarins and their habitat. She is the first to admit that, as an architect with no scientific background, she was an unlikely choice to lead efforts to protect the monkeys. But those who have worked with her say that what she lacks in formal scientific qualifications she makes up for with confidence, charisma, and negotiating savvy. “Stealing” Guillen from the Barranquilla Zoo was “the best thing I ever did,” says conservation biologist and Proyecto Tití founder Anne Savage. “I knew she would be perfect. She’s a great leader, she’s bilingual, and she’s an architect, which really helps with a lot of things.”

One key to Guillen’s success, many colleagues say, is her persistent yet gentle style of diplomacy. In 2011, she blocked construction of an airport that would have destroyed critical tití habitat and come uncomfortably close to one of Proyecto Tití’s major study sites. Diana Guzman, president of the Colombian Primatology Association, says she asked Guillen how she’d pulled off this feat—it seemed incredible. Guillen replied that instead of being confrontational, she had “kept her enemies close,” meeting many times with developers and government officials until she eventually convinced them of the need to protect the forest.

Guillen’s dedication has won her recognition not only from colleagues like Savage, but also from the wider conservation community. In 2015, she won a Whitley Fund for Nature Award, sometimes known as the “Green Oscar,” for her work with the monkeys.

With Guillen at the helm, Proyecto Tití is taking a three-pronged approach to cotton-top tamarin conservation: engaging rural Colombians, protecting the monkeys’ remaining forest, and curbing the illegal pet trade. One of Guillen’s most ambitious projects is a new system of wildlife corridors just west of the town of San Juan Nepomuceno, in the department of Bolívar. Those corridors will reclaim an additional 80 hectares (198 acres) of tití habitat.

Cotton-top tamarins are one of the world’s most endangered primates, with fewer than about 7,400 remaining in the wild. The International Union for Conservation of Nature (IUCN) designates them as Critically Endangered, in part because 92 percent of their historical habitat—the dry tropical forest with its towering ceiba and fruit-bearing yellow mombin trees—has been replaced with cow pasture, farm plots, and, most recently, palm oil plantations. The titís have gone from enjoying an estimated 9 million hectares (35,000 square miles) of forest, a region about the size of the state of Maine, to roaming a patchwork that totals just 720,000 hectares (2,800 square miles).

But while deforestation may be the cotton-top tamarins’ most present danger, it isn’t the only threat they’ve faced.

Decades ago, biomedical researchers discovered that titís were suitable subjects for studies of colitis and colon cancer treatments. In addition, behavioral scientists have long been interested in studying the monkeys’ cooperative breeding habits and reproductive hormones. But sustaining a lab colony of tamarins wasn’t a matter of making a one-time visit to the Colombian jungle, says Charles Snowdon, a professor emeritus at the University of Wisconsin who has studied cotton-top tamarins for decades. Because it’s hard to breed the species in captivity, Snowdon explains, researchers kept going back to the wild for more research subjects. From the early 1960s through the 1970s, an estimated 20,000 to 40,000 cotton-top tamarins were exported from Colombia to Europe and the United States, putting a significant dent in the wild population.

The costeños, it seemed, were never told that their primate neighbors were in trouble. When Snowdon first traveled to Colombia in the late 1980s, villagers he met thought the monkeys were as plentiful as squirrels—and they had no idea titís were unique to Colombia. “They thought we had them in the United States,” he says. Had the locals known, he believes, they might have protested the mass export.

In 1982, in response to the combined impacts and threats of habitat destruction and biomedical plundering, cotton-top tamarins were listed as endangered, and their export for medical research was halted. Despite their ongoing protected status, and their listing as a top-priority species by the Convention on International Trade in Endangered Species (CITES), however, titís continue to be illegally captured and moved out of Colombia. A simple Google or YouTube search will reveal how popular and far-flung the monkeys are as pets—for the same reasons Guillen fell in love with them. “Their sin is that beautiful white mane,” she says.

Once a week, Guillen travels to the bush to find wild cotton-top tamarins. Usually she heads to a small ranch in Santa Catalina, in the Colombian department of Bolívar, an hour-and-a-half drive southwest of Barranquilla. A few kilometers off the main road into the stubby hills, Guillen walks into the forest. The terrain is dry and sepia-colored for half the year, moist and verdant otherwise. Regardless of the season, what Guillen invariably stumbles onto is another chapter of the cotton-top histrionics that she and Proyecto Tití’s biologists have been following for more than a decade.

One member of troop in this patch of forest is an individual Guillen calls “Tamara,” a crabby old cotton-top she’s known for most of the monkey’s life. Now, at 16—an age seldom seen in the wild—Tamara has almost 30 offspring to her name. For years, like most cotton-tops, she was monogamous. But now she has a new partner: “Octavio,” a strapping three-year-old. Guillen says Tamara also has a history of strong-arming females who get in her way, including her own mother.

“It’s like sitting down to watch a soap opera,” says Guillen. “Oh, check out Tamara, she’s being so annoying,” she says, recounting a recent episode in which the matriarch was being particularly crotchety. Then, as if the camera were panning over to a young tamarin nearby, she continues: “Look at the young one, no one’s paying attention to him!” And then, as if suddenly recognizing the significance of the young tití’s solitude, she corrects herself: “No, what’s happening is they’re leaving him to learn things on his own.”

As the youngest of 10 children—8 of them boys—Guillen is no stranger to complex family dynamics. Seeing so many human-like behaviors exhibited by one-pound monkeys never ceases to fascinate her. In fact, titís’ social structure is in some ways much like our own, most notably in how families share the responsibility of raising young, a practice known as cooperative breeding.

Cotton-tops typically give birth to twins, each weighing about 10 percent of the mother’s weight. Tití mothers rely on their mates, brothers, and other relatives to help staff the tree-top daycare. Savage, who has been working with cotton-top tamarins in Colombia since 1987, has found that sometimes, unrelated monkeys also chip in, an unexpected behavior in the primate world—most animals tend to raise only offspring they are closely related to. Gorillas, orangutans, and chimpanzees, for example, don’t engage in cooperative breeding. Among those apes, only the mothers care for young. That makes tamarins unusual. Add these selfless rearing habits to the titís’ complex repertoire of vocalizations, and interesting hormonal responses that are likely connected to their social behaviors, and there are plenty of reasons to continue studying them.

“After seeing these animals in captivity, there is nothing more fascinating or impactful than seeing the animals in their natural habitat,” says Guillen. That makes their precarious status all the more wrenching, she says. “Colombia is a beautiful country filled with natural landscapes, from snow-capped peaks to deserts, savannas to tropical forests. But it’s missing a lot of protection from the government.” Although Colombian officials have recently begun paying more attention to preserving the country’s natural resources, Guillen fears the protections needed to safeguard the titís may come too late. “It’s frustrating because by the time the government makes a decision, you’ve already lost the forest.”

An hour past the Santa Catalina field site, Guillen is leading a new project that she started more than two decades after she met her first cotton-top tamarins and launched a career in conservation. Outside Los Colorados National Park, in collaboration with farmers and landowners, Guillen is designing a web of forested corridors, each at least thirty meters wide, so the cotton-tops can travel between larger patches of habitat. “We want to reverse the process of fragmentation that has occurred due to cattle ranching,” she says. “We’ve created a buffer around Los Colorados. The corridors we’re making are going to protect another 80 hectares.” Completing the project will require some land purchasing and negotiations with the local government and landowners, but Guillen is confident it will happen.

Once that’s done, Proyecto Tití’s tally of total forest it has protected will amount to more than 1,900 hectares, a little over 7 square miles. While Guillen knows that’s not a lot, it’s a start. After all, she says, protecting nature in Colombia is an uphill battle. As its decades-long civil war draws to an end, Colombia’s countryside is opening up to scientists, to tourists, and inevitably to business.

“We’ve been able to get to a lot of places we couldn’t before,” says Guillen. “But that’s a double-edged sword, because if we can get there, developers can get there too. Which is why we need careful planning from the government.”

Forest conservation isn’t the only tool in Proyecto Tití’s arsenal. At the heart of Guillen’s approach is her conviction that conservation work is synonymous with environmental education and income-generating community work. Towards that end, she is bringing the plight of the monkeys into the homes and schools of her fellow Colombians. Schoolchildren in the rural communities that abut the tití’s forests, for example, are learning about the cotton-top tamarins and the urgency of their conservation through coloring books, storytelling, and theater. Guillen and her team hope students will form an early bond with the monkeys and thus become a legion of stewards living near the titís. To combat the illegal pet trade, Proyecto Tití holds events boasting the virtues of keeping dogs rather than monkeys as pets. The wildlife trade is difficult to track, so it’s unclear how much these efforts have lowered the capture and sale of titís.

Proyecto Tití has also helped generate some modest income for people living near the tamarins’ habitat while also enlisting costeños to help draw attention to the animals’ plight and mitigate deforestation. Guillen says almost 100 local families are now involved in manufacturing tití-friendly products such as cotton-top tamarin plush toys and backpacks, plastic fence posts (to replace wooden fences), and cooking briquettes made from recycled organic waste instead of forest-sourced charcoal. Guillen hopes that all these activities will, by raising the profile of this special monkey, help stifle the pet trade, too.

The cultural sensitivity of Guillen’s approach has made it a model for animal conservation, says Guzman, of the Colombian Primatology Association. “What we’ve seen with Proyecto Tití is that they can change a paradigm, convince the community to value its natural resources, and make money off of the forest without defiling it,” she says. “They’re giving these communities a new identity.” Proyecto Tití’s model has also attracted attention from The Walt Disney Company, which has pledged money for the organization’s conservation and education programs. This is thanks in large part to Savage, Proyecto Tití’s founder and also the conservation director for Walt Disney Parks and Resorts.

The titís—and Guillen—still face an uphill battle. Proyecto Tití’s income-generating projects aren’t exactly get-rich-quick schemes—rural communities will need more support if they’re to resist the allure of deforestation. So far, the Colombian government has done little beyond preserving a few swaths of forest to support the cotton top tamarins’ conservation. And changing culture is a long process. Farmers have deeply held beliefs about the value of treeless pastures compared to intact forest; cattle ranchers know it’s cheaper to replace wooden fences twice a year than to invest in expensive plastic ones; and to many locals, the white-haired monkeys that swoop into their yards to steal fruit are nothing but a nuisance. For most rural Colombians, Guillen says, making ends meet will always outweigh protecting an endangered species.

“It’s a huge challenge,” she says as she prepares for another trip out into the field. “As with anything that depends on human nature in rural communities that have so many needs, it’s complicated.” That’s why conservation efforts need to include approaches that benefit everyone, she says. That message of mutual benefits of protecting the monkeys and the forest is what she brings to rural Colombians.

“What’s good for the tití is good for you, too. If you have forests, you have water, you have food sources, you have better climate regulation. And all that benefits us just like it benefits the tití. Don’t do this just because the tití is cute or Colombian. Do it because it will guarantee our food and physical security into the long term.”

Header image of pair of cotton-top tamarins by Lisa Hoffner
Unless otherwise noted, all other images by Ronald de Hommel

Aleszu Bajak

Aleszu Bajak, a freelance journalist based in Boston, grew up in Bogotá, Colombia. He now teaches journalism at Northeastern University and runs the blog In 2014, he was a Knight Science Journalism fellow at M.I.T.

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