Red-Mantle Saddle-Back Tamarin, Leontocebus lagonotus
RED-MANTLE SADDLE-BACK TAMARIN
Leontocebus lagonotus
Geographic Distribution and Habitat
The red-mantle saddle-back tamarin is found in the countries of Ecuador and Peru, between the Napo and Curary Rivers in the north, the Marañón River in the south, and the well-known Amazon River in the east. Within this range, they inhabit the mid-story and understory of Amazonian lowland forests, both in terra firma forest (simply put, dry land forests) and in seasonally flooded forest. They are able to survive close to human settlements. An adaptable species, they can be found in both primary forests, or those that are undisturbed by humans, as well as in secondary forests, those that have naturally regrown after a period of human-caused disturbance.
The red-mantle saddle-back tamarin was formerly considered to be a subspecies of the Andean saddleback tamarin (L. fuscicollis).
In addition, the red-mantle saddle-back tamarin was, along with all other saddle-back tamarins, once grouped into the genus Sanguinus. A taxonomic and genetic review conducted in 2016 found that saddle-back tamarins could be classified within their own genus (Leontocebus). However, this separation of genera is still debated among some biologists.
Size, Weight, and Lifespan
The red-mantle saddle-back tamarin has a head-body length of between 8.7-11 inches (220-270 mm), with a tail length between 10.8-13 inches (275-330 mm). Individuals weigh between 12-14 ounces (350-400 grams). Sexual dimorphism is not pronounced in the species; females and males look very much alike.
The life expectancy of wild red-mantle saddle-back tamarins is between eight and 13 years. Those in captivity have a maximum lifespan of 25 years.
Appearance
The red-mantle saddle-back tamarin is covered in a sleek, soft reddish or brownish fur coat, particularly on the shoulders and back, before fading to a reddish-brown hue around the rump. As evident by their name, the species has a brown or reddish “saddle” along the back. The underside of the body and limbs is reddish to black. Their feet, hands, ears, and tail are all black, and around the face things get interesting (and beautiful!) Near the black face, a distinct mantle (or collar) of long, red-brown hair covers the neck and shoulders, contrasting with the short white-gray hairs around the tamarin’s mouth and nose. Big brown expressive eyes are also encircled by white fur, and their black tails are non-prehensile, that is, not used for grabbing or grasping, but rather used to aid in balancing among the tree branches. Finally, their slender yet strong limbs have sharp claws to aid in gripping tree branches as they move throughout the forested habitat.
Diet
The red-mantle saddle-back tamarin hasn’t been studied in much detail in the wild, so much of the information has to be inferred from closely related species. If we look at the diet of the Illiger’s saddle-back tamarin (L. illigeri), the diet is composed of fruit, tree exudates such as sap and gum, flowers and their nectar, invertebrates such as spiders, snails, and insects, and small vertebrates such as lizards and frogs.
The dentation (teeth) of tamarins, unlike those of marmosets, which also feed on plant exudates, does not provide for gouging trees to stimulate the release of gum. Instead, they eat gum only when readily available.
Behavior and Lifestyle
Red-mantle saddle-back tamarins are diurnal, active during daylight hours, and arboreal, preferring to spend their time in the trees. Beyond this, very little is known about the behavior and lifestyle of this species, and must be inferred from other tamarin species. If we look at the Andean saddleback tamarin, they wake up at sunrise and spend almost the entire day foraging as a group, swinging or leaping acrobatically from branch to branch in search of food. They travel around 1.12 miles (1.8 km) per day, moving through the lower layers and forest understory, up to 32 feet (10 m) above the ground. Should they ever descend to the ground, they walk or run quadrupedally, or on all four limbs. Their strong claws help them to clamber back up into the relative safety of the trees.
As for sleeping habits, these can vary between tamarin species! What a conundrum for such a little-studied species as the red-mantle saddle-back tamarin (and me, writing this profile)! If we look at the sleeping habits of the black-mantled tamarin (L. nigricollis), they seek shelter in tree cavities or dense foliage during the night. They have been known to sleep in close proximity to one another, often curled up in a ball-like position. This provides them with protection from potential predators, as well as warmth. However, unlike humans, their sleep patterns tend not to be consolidated into one long stretch but instead may consist of multiple short episodes of sleep throughout the night.
Due to their small size, they are vulnerable to predators, particularly birds of prey such as the harpy eagle, snakes, and ocelots. If we look at the predator avoidance strategies of the black-mantled tamarin, they emit an alarm call, then beat a hasty retreat.
The genus Leontocebus is informally known as the “white-mouthed group” of tamarins, in reference to the white fur found on their faces.
Red-mantle saddle-back tamarins live in family groups of two to nine individuals, comprised of an adult male and female, and their (likely immature) offspring. It is not known if other adult members, whether related to the dominant pair or not, make up a portion of the group. This tamarin species is known to defend its territory against strangers; chases and fights may occur. However, not all encounters between neighboring groups are aggressive—some are peaceful.
At this time, that’s all that is known for certain! Once again: More research is needed on this species! It’s possible that, like the black-mantled tamarin, members of both genders tend to leave their birth groups once mature to form groups of their own. If we look at the Andean saddleback tamarin, home range size depends on the availability of food sources, and varies with the seasons, fluctuating from 39.5 to 297 acres (16–120 ha). Home ranges often overlap with those of other tamarin groups, so interactions are common. Monkeys from different groups often feed, unbothered by their neighbors’ presence. Some of these interactions with neighboring tamarins include grooming and playing, and, sometimes, even mating occurs with the outsiders! According to wildlife biologists, friendly encounters between groups serve specific functions. Foremost, larger numbers provide a greater defense of resources. This practice also provides the opportunity for non-sexually mature individuals and non-breeding adults to get to know potential mates from neighboring groups. For individuals who engage in mating with members from another group, migration from one group to another is known to occur. At least there’s a sense of familiarity…
While interactions with other primate species have not been studied for the red-mantle saddle-back tamarin, if we look at the Andean saddleback tamarin, sympatric primate species, or those that tend to occur within the same area, include western pygmy marmosets (Cebuella pygmaea), Goeldi’s marmosets (Callimico goeldii), and moustached tamarins (Tamarinus mystax). Wildlife biologists believe that these mixed-species associations may be a strategy of protection against predators, with “safety in numbers”.
No information is available regarding the red-mantle saddle-back tamarin and their communication repertoire, and again must be inferred from information on closely related species. If we look, once again, at the black-mantled tamarin, their primary method of communication is a unique repertoire of vocalizations, which include bird-like whistles and frog-like croaks. They recognize the alarm calls of other saddle-back tamarin species as a means of reacting to and avoiding predators.
Besides vocalizations, grooming is a common means of maintaining social bonds within the group, and anogenital (i.e., rear-end) scent marking has been observed. Sometimes, this scent marking is done in succession by several individuals, with each subsequent individual smelling the place rubbed by the previous individual.
Very little is known regarding the reproduction and family habits of the red-mantle saddle-back tamarin, and must be inferred from that of closely related species. The only facts known for certain are that gestation (pregnancy) lasts for around 140 days, and twin births are common. In addition, infants are carried around by the adult male and are only given back to Mom for feeding.
If we look for one final time at the black-mantled tamarin, they reproduce year-round, with no set breeding season. Like other species of saddle-back tamarins, their sexual patterns can be a bit flexible. If there is a single breeding female, or at least a more dominant female among the others within the group, she is often monogamous, breeding with one adult male. However, if multiple adult males are present, she may reproduce with any one of them, with no aggression between the males, to boot! How… understanding and cooperative. The latter form of reproduction is known as polyandry. The birth interval, or time between births, is around five months.
Please note that the next two paragraphs continue to be based upon information known about the black-mantled tamarin, despite a specific known parenting difference with the red-mantle saddle-back tamarin. The young of the black-mantled tamarin are dependent upon Mom for protection and guidance, while those of the red-mantle saddle-back tamarin primarily rely upon Dad. At around two to three months of age, young will begin to venture away from their caretaker’s back and explore the environment on their own. However, they still maintain close proximity to their parent for protection and guidance.
The babies are incredibly small at birth, weighing only around 1.4 ounces (40 g). They are completely dependent on the caretaker parent for survival, and spend the majority of their time clinging to his or her back. At around six to eight months of age, the young begin to consume solid food, gradually weaning off their mother’s milk. As they grow older, the young continue to learn essential skills from their parents as well as from other group members. They observe and imitate adult behaviors, such as foraging techniques and social interactions, which are crucial for their survival in the wild. They reach sexual maturity and thus, adulthood, at around two to three years of age, upon which they leave to form groups of their own.
I’ve said it before, and I’ll say it again: More research is desperately needed regarding the life history of the red-mantle saddle-back tamarin!
As some of their diet consists of fruit, the red-mantle saddle-back tamarin aids in the regeneration of their forest habitat by dispersing seeds through their feces as they move around their habitat. As a prey species, they also play a role in feeding local predators within the habitat. They additionally play a role in pollination. Like bees and butterflies, they collect pollen from flowers while drinking nectar. They then deposit the pollen on each flower they visit, thereby pollinating the plants. Finally, they may also be considered pest controllers through their consumption of insects.
The International Union for Conservation of Nature lists the red-mantle saddle-back tamarin as Least Concern (IUCN, 2015), appearing on the IUCN Red List of Threatened Species.
The red-mantle saddle-back tamarin is a common species throughout its range. Despite being listed as Least Concern by the IUCN, they are considered Near Threatened in Ecuador, mainly due to the high rates of deforestation and fragmentation of the Amazonian forests. The red-mantle saddle-back tamarin is also hunted for the pet trade, posing another potential threat to the survival of the species.
The red-mantle saddle-back tamarin is listed in Appendix II of the Convention on International Trade in Endangered Species (CITES), an international agreement between governments whose goal is to ensure that international trade in specimens of wild animals and plants does not threaten their survival.
The red-mantle saddle-back tamarin is found in Yasuní National Park, Sumaco-Napo Galeras National Park, and in three private reserves (Jatun Sacha, Selva Viva, Yanacocha) in Ecuador, as well as the Reserva Nacional Park in Peru.
Conservation actions needed include any necessary steps to combat the high rates of deforestation and fragmentation of the Amazonian forests in Ecuador, as well as cracking down on the pet trade targeting the red-mantle saddle-back tamarin. In addition, an ENORMOUS amount of research on the life history of the red-mantle saddle-back tamarin is necessary, should they continue to be a common species found in parts of the South American continent.
- https://www.alltheworldsprimates.org/Members/Home/MasterPrimate.aspx?tid=1350
- https://www.bioexplorer.net/animals/mammals/monkeys/red-mantled-saddle-back-tamarin/
- https://en.wikipedia.org/wiki/Red-mantled_saddle-back_tamarin
- https://www.iucnredlist.org/species/43950/17980627
- https://www.zoo-leipzig.de/en/animal/rotschultertamarin/
Written by Sienna Weinstein, April 2025