MOTTLE-FACE TAMARIN

Tamarinus inustus

Geographic Distribution and Habitat

The mottled-face tamarin (or mottle-face tamarin) is found in Brazil and Colombia. They occur in a variety of habitats between the two countries, including lowland forests, flooded forests, dry terra firma forests, and the unique white sand ecosystems known as Campina and Campinarana. Both Campina and Campinarana differ from other Amazonian habitats not only by the name-sake white sand but they also lack of nutrients in the soil. Because of this, the plants need to be highly specialized to uptake all the nutrients they can, and many of the plant species found in the white sand forests are endemic (meaning they can only be found in that area). Similar to other tamarins, the mottled-faced tamarin is abundant in secondary forests that have regrown after experiencing human disturbance compared to primary forests that have grown undisturbed.

TAXONOMIC NOTES

Originally, scientists classified all tamarins as a single genus: Saguinus. As scientists studied tamarins more over time, they started to realize not all tamarin species were as closely related as they previously thought, and began finding more accurate ways of classifying the group. One of the more recent updates to tamarin taxonomy has been the recognition of three distinct genera of tamarin instead of one, bringing the introduction of Tamarinus and Oedipomidas. With the genera now being split three ways, the mottled-face tamarin was moved to the Tamarinus genus, along with the moustached tamarin, white-lipped tamarin, and emperor tamarin. Scientists made this decision based on genetic differences, which are also supported by morphological, behavioral, and geographic differences.

Mottle-face tamarin range, IUCN 2024

Size, Weight, and Lifespan

Mottled-face tamarins are particularly small monkeys, with a head-body length of 8.19–10.20 inches (20.8–25.9 cm) and a tail length of 12.99–16.14 inches (33–41 cm). They are not sexually dimorphic, which means that males and females are similar in size. Their lifespan is currently unknown but is likely similar to other tamarins which can live up to about 25 years in captivity and just under 20 years in the wild.

Appearance

The word “mottle” describes the irregular swatches of white on the mottled-face tamarin’s face. Other than these markings, they are almost completely black over the rest of their body. The edges of the long cape-like fur (or mantle) on their back can be reddish-brown in color. Males can be easy to identify by the appearance of the exposed white skin on their genitals. Although the mottled-face tamarins’ pointed ears do make them look a bit like a gremlin that was fed after midnight (from the 1984 movie, “Gremlins“), we still think they’re cute in their own way.

Photo: © Josh Vandermeulen/iNaturalist/Creative Commons
Diet

Similar to other tamarin species, mottled-faced tamarins are primarily frugivores and have been observed consuming fruit from at least 23 different plant species. They’ve also been seen eating spiders and insects. Similar to other tamarin species, mottled-face tamarins forage from small fruit patches near the forest floor. Scientists believe this foraging behavior allows the small tamarins to avoid competition with the larger fruit-eating monkeys that they share territory with.

Other tamarins have been observed eating small vertebrates such as lizards and frogs. Catching prey is more difficult and occurs less frequently than eating fruit, so although this has not been observed in mottled-faced tamarins they may also enjoy an occasional lizard lunch that has yet to be recorded by researchers.

Behavior and Lifestyle

As the least studied species of tamarin, there have only been a handful of somewhat short-term studies on mottled-face tamarins, so much of our understanding of them is a bit fuzzy. From a study on a single wild group, we can estimate their home range is about 0.14 square miles (35 ha), and they will travel about 0.60 miles (961 m) in a day. Because this is based on a single group over a short period of time, we can expect these numbers to be updated with future studies.

Mottled-face tamarins are arboreal and don’t descend to the ground except occasionally to quickly grab dropped food. They are active during the day and rest together at night. As the studies on mottled-face tamarins are limited, our understanding of their behavior is as well. Based on what we know about other tamarins, they likely are fairly peaceful between group members and rarely show aggression. Aggression can increase when there are changes in the group’s dynamic or over food.

Mottled-faced tamarins have been observed in association with double-toothed kites. Locals believe this is due to predation from the kites on the tamarins. However, researchers have not observed instances of predation and double-toothed kites primarily eat insects (although they will sometimes eat other small vertebrates, so predation on tamarins is not entirely unimaginable). Birds with similar diets have been observed foraging alongside other primate species (including other tamarins) because it’s easier for them to catch insects that are evading the primates. Researchers think this is more likely the reason for the association between double-toothed kites and mottled-face tamarins than predation.

Fun Facts

They are referred to by locals as hueviblanco (or “white-egg”) due to the striking appearance of bare white skin of the males’ genitalia against their black fur.

Daily Life and Group Dynamics

Mottled-face tamarins have been observed in group sizes of 3–11 individuals. Although long-term studies on the group dynamics of mottled-faced tamarins are limited, there are some general patterns observed in other tamarin species that likely also apply to mottled-faced tamarins. Both males and females may leave their natal group (the group they were born into) and join a new group as they reach maturity. Some individuals may decide to stick around in their natal group for longer though. Females will sometimes “float” on their own near other groups until there is space for a breeding female, or until she finds more emigrating tamarins to form a new group.

They share their habitat with squirrel monkeys, tufted capuchins, Humboldt’s white-fronted capuchins, collared titi, red howler monkeys, and black-headed uakari. They also overlap in range with noisy night monkeys, although due to differences in sleeping habits are unlikely to interact with them.

Communication

How mottled-face tamarins communicate hasn’t been studied as of yet, but there have been extensive studies on the communication methods of other tamarin species. Tamarins are known for having complex multimodal communication systems, utilizing vocalizations, facial expressions, and scent. Their vocal repertoires are made up of species-specific chirps and trills for communicating affiliation, group location, and alarm calls. A distinctive facial expression used by many tamarin species is tongue-flicking, which is typically used by females to flirt with males. Both sexes will also scentmark to signal their sexual status to each other. Although the specifics of how these methods of communication may differ for mottled-face tamarins, these generalized behaviors from other tamarin species give us a good starting point for understanding them.

Reproduction and Family

There have not been any in-depth studies of mottled-face tamarin reproduction as of yet, but we can make some assumptions based on other tamarin species. Tamarins most commonly give birth to twins, but may sometimes have a single infant, triplets, or (rarely) quadruplets. Typically, however, only two infants are likely to survive. Tamarins typically have a gestation length falling between 4–6 months, so we can guess that mottled-face tamarins will also fall into this range. Births occur once a year, often during the start of the rainy season when the most fruit is available. Females typically reach sexual maturity around 1 year of age, while males are a little bit slower to mature at around 1-1.5 years of age. Tamarins are characterized by reproductive suppression of the lower-ranking females in the group, meaning only the dominant female will give birth. There may be more than one breeding male in a group at a time. The males will also provide parental care by carrying babies on their backs. Females other than the mother will also assist in infant care. This “it takes a village” approach to infant care is referred to as cooperative breeding by researchers.

© Jeanne Benioff/iNaturalist/Creative Commons
Ecological Role

Given their diet and the identified ecological role of other tamarins, mottled-face tamarins likely act as seed dispersers. While their small size limits the amount of seeds tamarins are able to disperse compared to the larger primates found in Latin America, tamarins are typically more abundant in secondary forests. Because secondary forests typically have lower plant diversity than primary forests, this adds a unique level of importance to tamarins’ role as seed dispersers. As tamarins move between primary forests to degraded areas, they’ll disperse seeds as they travel, helping in the regeneration of damaged or fragmented forests.

Conservation Status and Threats

The mottled-face tamarin is classified as Least Concern by the International Union for Conservation of Nature (IUCN, 2015), appearing on the IUCN Red List of Threatened Species. The population is expected to remain stable. Compared to many other primates in South America, mottled-faced tamarins have been fairly lucky and have not experienced much human disturbance in their range. Where disturbances have occurred, mottled-faced tamarins have shown a promising ability to adapt to the changes in their habitat. Because of their small size, they are not hunted for bushmeat. Sometimes, however, they will be captured and sold as pets.

Conservation Efforts

Mottled-faced tamarins are 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.

There are no specific conservation efforts currently in place for mottled-face tamarins as they are one of the few primate species not experiencing any major threats, and their range is mostly on protected lands. As deforestation and climate change persist, however, this may be subject to change. At this time, most researchers urge the continued study of the species in order to implement the most effective conservation strategies for them if/when it becomes necessary.

References:
  • https://cites.org/eng/app/appendices.php
  • https://www.iucnredlist.org/species/41523/192552160
  • Lopes, G. P., Rohe, F., Bertuol, F., Polo, É., Valsecchi, J., Santos, T. C. M., … & Hrbek, T. (2023). Molecular systematics of tamarins with emphasis on genus Tamarinus (Primates, Callitrichidae). Zoologica Scripta, 52(6), 556-570.
  • Brcko, I. C., Carneiro, J., Ruiz-Garcia, M., Boubli, J. P., e Silva-Júnior, J. D. S., Farias, I., … & Sampaio, I. (2022). Phylogenetics and an updated taxonomic status of the Tamarins (Callitrichinae, Cebidae). Molecular Phylogenetics and Evolution, 173, 107504.
  • CAQUETÁ, L. R. (2004). PRELIMINARY OBSERVATIONS ON THE MOTTLED. Neotropical Primates, 12(3), 123.
  • de Souza, L. L., Queiroz, H. L., & Ayres, J. M. (2004). The mottled-face tamarin, Saguinus inustus, in the Amanã Sustainable Development Reserve, Amazonas, Brazil. Neotropical Primates, 12(3), 121-122.
  • Stevenson, P. R., Guzmán, D. C., & Defler, T. R. (2010). Conservation of Colombian primates: an analysis of published research. Tropical Conservation Science, 3(1), 45-62.
  • Valsecchi, J., Vieira, T. M., Silva Júnior, J. S., Muniz, I. C. M., & Avelar, A. A. (2010). New data on the ecology and geographic distribution of Saguinus inustus Schwarz, 1951 (Primates, Callitrichidae). Brazilian Journal of Biology, 70, 229-233.
  • Tardif, S. D., Araujo, A., Arruda, M. F., French, J. A., Sousa, M. B. C., & Yamamoto, M. E. (2008). Reproduction and aging in marmosets and tamarins. In Primate reproductive aging (Vol. 36, pp. 29-48). Karger Publishers.
  • Heymann, E. W., Fuzessy, L., & Culot, L. (2022). Small but Nice–seed dispersal by Tamarins compared to large neotropical primates. Diversity, 14(12), 1033.
  • Digby, L. J., Ferrari, S. F., & Saltzman, W. (2011). Callitrichines The Role of Competition in Cooperatively Breeding Species. In Primates in Perspective (second, pp. 91-107). Oxford University.
  • Poirier, A. C., Waterhouse, J. S., Dunn, J. C., & Smith, A. C. (2021). Scent marks signal species, sex, and reproductive status in tamarins (Saguinus spp., Neotropical Primates). Chemical senses, 46, bjab008.

Written by Lina Rademacher, September 2024