- Less than 2,000 northern and southern muriqui live on in the remaining fragments of Brazil’s Atlantic forest.
- Karen Strier and other researchers — many of them her former students — have taken up the cause of protecting these unique primates, with a good deal of success.
- For $150,000 US, “the equivalent of a few SCUD missiles, we could save the largest population of northern muriquis for posterity,” says Strier. Another $300,000 would protect critical habitat for the southern species.
Muriquis often start their day by hugging one another. The Brazilian monkeys can become so entwined in lanky arms and prehensile tails, around tree limbs and each other, that it’s hard to tell them apart. Their sociability doesn’t end there. These primates don’t fight over food, sex or sleeping arrangements — an easygoing lifestyle that earned them the moniker “hippie monkeys.”
However, such peaceful ways belie the muriqui’s fight for survival.
Tucked up in the trees of the Atlantic forest — a once-green corridor stretching along the east coast of Brazil, now largely deforested — the northern muriqui (Brachyteles hypoxanthus) has clung to the IUCN’s Critically Endangered list for more than 25 years.
Just this year, the southern muriqui (Brachyteles arachnoides) joined them on that list. Like many endangered species, the combined pressures of deforestation, fragmented habitats and hunting have steadily driven populations downward. By best estimates, less than 2,000 of both muriqui species remain.
On the surface, these surviving monkeys seem fortunate. Many populations live in state parks, federal reserves, or privately owned areas where they are protected. The woolly-coated creatures are also considered a flagship species of the Atlantic forest, and included in national and regional action plans for conservation. Still, the monkeys need even greater support to avoid slipping from their Most Endangered status toward extinction.
The muriqui nobody knows
“The muriqui really suffer from a lack of presence,” said Russell Mittermeier, executive vice chair of Conservation International and chair of the IUCN primates specialist group. “The pubic never sees them because there are so few in captivity. Even in Brazil, where these primates are the largest mammals endemic to the country, people don’t know they exist.”
This low profile persists despite the animal’s appearance on two postage stamps and a big campaign (failed) to make the muriqui the mascot for the 2016 Rio Olympics. However, one media event has been paying dividends for more than three decades of muriqui conservation: a documentary called “Cry of the Muriqui,” created by a Harvard University student and produced by the World Wildlife Fund-U.S. Primate Program. The film highlights the plight of muriquis and lion tamarins.
The movie didn’t blow out Hollywood box offices. But it impelled an anthropology grad student, Karen Strier, to visit Mittermeier’s research station in Brazil where the filming took place. She arrived at the Estação Biologica de Caratinga in 1982 — a preserve later renamed the RPPN-Feliciano Miguel Abdala after the man who permanently conserved this federally protected private reserve.
When Strier first saw the muriquis, she was utterly captivated; the animals transformed her life. Today, the Caratinga preserve and research station, now under her leadership and supported by her many colleagues, can boast one of the longest-running primate studies in South America.
Pioneering primate research
Strier’s early work at Caratinga played a pivotal role in advancing our understanding of primates. When she first described the muriqui’s egalitarian society, her research turned the prevailing primate behavior paradigm upside down.
Before the muriqui — and Strier’s research team — showed us differently, all primates were thought to lead competitive, aggressive lives like the breast-beating baboons and gorillas. However, years of observing these monkeys living in easygoing groups, without dominance hierarchies among males or females, pointed toward other possibilities, which Strier detailed in her first book, Faces in the Forest.
“We’ve learned a lot more about other primates and filled in the gaps in that behavior continuum, but the muriquis still hold to the peaceful extreme end of that,” said Strier, now a professor of anthropology and zoology at the University of Madison Wisconsin.
Strier continues to document the rise of the northern muriqui population at the Caratinga Biological Station, from a low of 22 to the current high of more than 354 individuals; five new babies were recently sighted.
She has monitored the population as its steady growth strains at the confines of a fragmented habitat, prompting new muriqui behaviors. The arboreal animals who once rarely lowered themselves to the forest floor, now spend hours a day scuffing along the ground. The monkeys forage in the leaf litter for new types of leafy or fruity food; they mate, and even take naps there — all risky behaviors for primates that are prey to other ground-dwelling animals such as puma.
“The way muriqui are responding to increased population density reveals their capacity for behavioral flexibility,” said Strier, who also co-directs a working group that writes comparative studies about the life histories of different primates. “It makes me more optimistic that what we’re watching is a process of their population recovering from being pushed to the edge.”
It’s not exactly an overnight success story, since the muriqui are still considered Critically Endangered. However, Strier’s project showcases some hallmarks of other successful conservation programs. For example, on the project’s 30th anniversary the nearby city of Caratinga bestowed honorary citizenship upon Strier as testimony to the deep ties that she and her colleagues conscientiously forged with local people.
Another hallmark of such farseeing conservation work is the depth of training available at the research station for Brazilian students. Many of these young academics have gone on to lead their own muriqui studies.
A broadened research effort
The northern muriqui have a stalwart champion in Fabiano Rodrigues de Melo, a professor at the Universidade Federal de Goiás, who recently spent a year as a postdoctoral fellow working with Strier at the University of Wisconsin-Madison.
“I’m always trying to find an opportunity to protect the muriquis,” said Melo. Among his many conservation roles, he sits along with Strier on the advisory board of the Muriqui National Action Plan. This Brazilian initiative was officially approved in 2010 by the Chico Mendes Institute, with a goal to “reduce at least one extinction category level for both [muriqui] species by 2020.”
He also started the Muriqui Institute for Biodiversity in hopes of increasing conservation grants to preserve the monkeys and other species. But Melo doesn’t spend much time sitting at his desk. Creating a selective breeding program for the muriqui is a top priority. This hasn’t been easy, because few of these monkeys are in captivity. Moreover, the wild female Melo picked out to start the program prefers her freedom; Socorro, as she is called, has eluded capture for the last four years. When she is finally caught, a solo male named Zidane awaits her arrival at the Fundação Zoo-Botânica.
Melo also gathers information about smaller isolated monkey populations. Of the approximately 1,000 northern muriqui left in Brazil, less than 400 live on the Caratinga reserve, which leaves a lot of unstudied monkeys about which little is known. When Melo locates isolated muriqui populations, he is especially interested in obtaining data on their genetic diversity. In small, scattered groups, genetically impoverished monkeys are more susceptible to disease and less resilient in the face of environmental changes.
Rallying to the Muriqui cause
Another of Strier’s long-term colleagues is Sérgio Lucena Mendes, who now coordinates an Instituto de Pesquisas da Mata Atlântica (IPEMA) project that follows about 100 northern muriqui scattered throughout a patchwork of privately owned forest fragments in Santa Maria de Jétiba. Mendes was a fellow student when he met Strier decades ago — both were studying primates in the same stretch of forest.
“My work encompasses population monitoring, landscape ecology, genetics, and scientific education aiming to propose and execute actions to protect a muriqui population in the Espírito Santo State,” said Mendes, now a professor at the Universidade Federal do Espírito Santo. “We also prepared an action plan to preserve the muriquis in this region and we are participating in the National Action Plan (PAN) to protect both muriqui species.”
Further south, the muriquis have benefitted from the interest of former Strier student, Mauricio Talebi. Now president of the Associação Pró-Muriqui, and professor at the Universidade Federal de São Paulo, he has studied the southern species for 15 years. About 90 percent of these monkeys are in the state of São Paulo, especially in the Carlos Botelho State Park, with a few groups in the city of Rio de Janeiro and Parana State. Although they live on protected lands, these monkeys are challenged by hunters far more than fragmented habitat.
Talebi earned a degree in veterinary medicine, but he developed a passion for primates before he began clinical practice. The muriqui intrigue him, not only for their big size — they average about 20 pounds — but also for their critical role in spreading plant seeds throughout the forest.
“To me, they are poetic,” said Talebi. “These monkeys are forest gardeners, a very important function. If the muriquis go extinct, then in two or three decades these forests will experience a much smaller diversity of trees.”
Northern and southern muriqui variations
Interestingly, the “hippie” behaviors chronicled by Strier up north are not always demonstrated by the southern species. “Imagine,” said Talebi, “I enter this forest, and everything I studied about the peaceful muriqui is completely different here. These monkeys are competing for food and teasing each other. So science knows one monkey, but I am starting to learn about another.”
In the past five years, Talebi has focused on this “new frontier” in southern muriqui science by systematically monitoring population demographics. “For species on the verge of extinction, it’s okay to look at one population where everything seems to be going well,” he said. “But we need to monitor the isolated, smaller populations, too.”
His main study site is the Carlos Botelho State Park, a fully protected area harboring an estimated 600 to 800 muriqui. Talebi is also comparing four other fragmented field sites spread across the state of São Paulo, where a total of maybe 100 monkeys remain. Much of the funding for these projects comes from FUNBIO, the Brazilian Fund for Biodiversity, and from big companies, such as paper manufacturers Fibria Papel e Celulose and Klabin S/A, that want to improve their environmental images.
Talebi also checks on previously reported muriqui groups. In many places where there were once healthy populations, he’s finding no trace of the animals. The discovery of local extinctions on such a large scale was the prime reason the southern muriquis’ endangered status was heightened this year, he said.
Despite these discouraging findings, the muriqui conservation landscape is improving. For muriquis in the Caratinga reserve, the key is to find more living room so the expanded population can continue growing. Strier is optimistic about the naturally occurring reforestation of abandoned farmlands adjoining the preserve which could provide new habitat for the monkeys.
Smaller groups of northern muriqui likely need different management strategies, she said, such as translocating females between groups to maximize breeding and genetic diversity.
For the southern muriqui, Talebi outlines multiple conservation approaches: outreach and education to increase the perceived value of the muriqui by the public; improving corridors between “islands” of forest to join isolated monkey groups; and the training of the next generation of scientists to carry on Strier’s tradition of research and conservation.
Although government and corporate assistance have aided muriqui conservation, it’s always a struggle to keep enough money in the coffers.
By Talebi’s accounting, efforts to save southern muriquis have cost about $50,000 US each year during the last ten years, with another $100,000 invested in buying lands to provide almost-pristine habitat for the monkeys. To assure a future for the muriquis, those funds would need to double each year, he said. More critically, about $300,000 is needed to buy one final piece of land that would safeguard the home range of the main population of southern muriqui.
For the northern muriqui in Caratinga, Strier calculated that yearly costs run about $100,000 to maintain ongoing research and support the personnel who work for the Reserve and provide infrastructure. As a private reserve, there are no federal or state funds. Ideally, a better future for the monkeys would include an expanded forest and more staff on the Reserve to help with tourists and educational projects. Those plans could push annual expenses closer to $150,000 for this one site, where more than one-third of the northern muriqui population lives.
“What we need for Caratinga, and would welcome from one or more donors, is to establish a trust fund,” said Strier. A $3 million trust with a five percent interest rate could yield $150,000 each year to cover operating costs and research. “For the equivalent of a few SCUD missiles, we could save the largest population of northern muriquis for posterity, continue to study it, and still have funds left over to help support management projects elsewhere,” she said.
Money isn’t the only thing muriqui conservation needs. Although donations to any of the muriqui conservation groups are clearly welcome, volunteers with specific skills or expertise can also be valuable to the researchers.
Talebi, for instance, said he could benefit greatly from the services of a “cool website designer” for his new NGO, a task that could be accomplished without ever stamping a passport. He also invites university students to pursue their studies at his muriqui research sites. Ecotourism is becoming a resource for muriqui conservation as well, benefiting the communities and people that share their forest habitat.
“The main challenge for the next 30 years is: How can we harness the creativity of people — not just scientists and government — to save these incredible monkeys?” said Talebi.