Saguinus tripartitus

Geographic Range

Saguinus tripartitus occurs in the upper Amazon rainforest between the Rio Curaray in Ecuador and the Rio Napo in Peru. It can also be found east of the Andes between the right bank of the Rio Napo and the left bank of the Rio Putumayo in Ecuador.

• Biogeographic Regions
• neotropical neotropical
  • native native

Habitat

Saguinus tripartitus is found in lowland evergreen rainforests, seasonally flooded forests, and terra firma of the Amazon basin. Although typically found at lower elevations, S. tripartitus has been recorded at up to 400 meters above sea level in the western limits of its range, near the Andes Mountains. In general, tamarins are highly arboreal and are rarely seen on the ground.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• rainforest rainforest

Physical Description

Saguinus tripartitus can range from 218 to 240 mm in body length and 316 to 341 mm in tail length. They have orange bodies and blackish orange hands. Their heads are covered in black fur with muzzles and faces which are generally white. On their lower back is a patch of cream colored hair. Their tails are generally black with an orange underside. This species is also closely related to Saguinus fuscicollis . Some investigators consider S. tripartitus to be a subspecies of S. fuscicollis .

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

Saguinus tripartitus , like other callitrichids , live in groups in which only the dominant female mates, typically with multiple males. There is some evidence of facultative polyandry among tamarins, in which two or more males mate with the female and cooperate in caring for the twin offspring.

• Mating System
• polyandrous polyandrous
• cooperative breeder cooperative breeder

Saguinus tripartitus , like other callitrichids , live in groups in which only the dominant female mates. As in other callitrichid species, the ovarian cycles of subordinate S. tripartitus females are suppressed while living in groups. In studies involving captive females living in family groups, low and acyclic levels of urinary estradiol (a hormone produced by the ovaries) were recorded while females were living as subordinates. When females were removed from the family group and placed in isolation with a male, their levels of urinary estradiol skyrocketed and immediate onset of their ovarian cycles occurred. The physiological reasons behind this are not known, but it is speculated that pheromones from dominant females may play a part in suppression of ovarian cycles in subordinate females. The length of gestation and lactation periods, breeding seasons and intervals, and time to sexual maturity, are not known. They are believed to be similar to other members of the genus Saguinus in terms of these traits. Gestation periods for Saguinus range from 140 days to 180 days, with most species having gestation periods between 140 and 150 days. Information regarding lactation periods of Saguinus could not be found. No generalizations could be made about the breeding seasons of the whole genus based on the information available. However, Saguinus fuscicollis breeds between April and October, and Saguinus oedipus and Saguinus geoffroyi breed between January and February. The age to sexual maturity varies between 15 and 24 months for Saguinus species.

Like other tamarin species, S. tripartitus gives birth to twins.

• Key Reproductive Features
• iteroparous iteroparous
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• viviparous viviparous

Patterns and duration of parental investment are not known. Fathers tend to provide and care for the infants more than mothers do after they are born. This may be offset the substantial energy investment of the mother during gestation and lactation. Tamarins give birth to young with large body masses relative to the mother's body mass, so females invest large amounts of energy into the young before they are born. Post-birth care from parents comes in the form of providing food, providing protection, and carrying the young around as they develop. Social groups also help to care for the young, sharing food and generally protecting them.

• Parental Investment
• altricial altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male

Lifespan/Longevity

Little information is available about the lifespan of Saguinus tripartitus . Rowe (1996) lists lifespan in the wild as 6 years and Hershkovitz (1977) mentions one specimen living five years, nine months, and nineteen days in captivity.

Behavior

Saguinus tripartitus individuals are very social. There are definite social hierarchies among groups, but these hierarchies have not been studied. Groups generally include 2 to 8 (maximum 15) members. The average group size is 5.3 individuals. These social hierarchies are maintained through the use of scent marking. Saguinus tripartitus individuals are arboreal and rarely seen on the ground.

• Key Behaviors
• arboreal arboreal
• scansorial
• diurnal diurnal
• motile motile
• sedentary sedentary
• territorial territorial
• social social
• dominance hierarchies dominance hierarchies

Home Range

No information could be found regarding the home range of Sagunius tripartitus . They have been documented as having a population density of 13.5 individuals per square kilometer.

Communication and Perception

Saguinus tripartitus primarily uses scents in communication. Individuals use circumgenital marking (marking using glands surrounding the anus) and suprapubic marking (marking using suprapubic glands). Individuals of higher social rank mark more frequently than those of a lower social standing. Saguinus tripartitus individuals can distinguish a large amount of information from scents, such as sex, species, social rank and reproductive status.

• Communication Channels
• visual visual
• acoustic acoustic
• chemical chemical

• Other Communication Modes
• scent marks scent marks

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Saguinus tripartitus is primarily insectivorous and frugivorous. They have also been known to eat small vertebrates, non-insect arthropods, flowers, nectars, gums, and other plant exudates. They may feed less on exudates than some other primates because they lack the dentary adaptations of those species for gouging into plants.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore
• herbivore herbivore
  • frugivore frugivore

• Animal Foods
• reptiles
• insects
• terrestrial non-insect arthropods

• Plant Foods
• fruit
• nectar
• flowers
• sap or other plant fluids

Predation

Saguinus tripartitus individuals are preyed on by a variety of animals including birds of prey, snakes, ocelots, and tayras. They use several behaviors to protect themselves from these predators. They differentiate between the fecal scents of predators and non-predators in order to avoid areas which may have predators in them. They use specific warning calls which can alert others nearby if the threat is aerial or terrestrial. They sometimes mob predators.

Ecosystem Roles

In its ecosystem, Saguinus tripartitus is important for its role as prey for larger animals. Most often these are birds of prey. It also has a small role as a predator of insects and very small vertebrates. It is also possible that the diet of S. tripartitus makes them important in seed dispersal and the pollination of flowers.

• Ecosystem Impact
• disperses seeds
• pollinates

Economic Importance for Humans: Positive

Saguinus tripartitus individuals are sometimes kept as pets. Because they are small, they are rarely hunted for food. They are also used as models in biomedical research.

• Positive Impacts
• pet trade pet trade
• research and education

Economic Importance for Humans: Negative

There are no known adverse effects of Saguinus tripartitus on humans.

Conservation Status

Saguinus tripartitus is listed as "Near Threatened" by the International Union for Conservation of Nature and Natural Resources (IUCN). Saguinus tripartitus occurs in remote forests along the Rio Yasuni. Human activities have not greatly impacted these forests to date, with the exception of small petroleum prospecting encampments. However, the recent discovery of petroleum in the area has led to the construction of the Pompeya-Iro highway through the area, which has caused some concern about future deforestation and development in the habitat of S. tripartitus . Due to projected high rates of deforestation, the population of S. tripartitus is expected to decline by twenty-five percent over the next eighteen years (three generations).

Additional Links

Encyclopedia of Life

Contributors

Justin Carter (author), University of Michigan-Ann Arbor, Lauren Hall (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor, Tanya Dewey (editor), Animal Diversity Web.

References

Abbot, D., J. Barrett, A. Belcher, et al.. 1993. Marmosets and Tamarins: Systematics, Behaviour, and Ecology . United States: Oxford University Press.

Emmons, L. 1990. Neotropical Rainforst Mammals . United States of America: The University of Chicago Press.

Grizmek, B. 2003. Family: New World Monkeys II. Pp. 127-128 in Grzimek's Animal Life Encylopedia , Vol. Volume 14, Second Edition. Detroit: Gale.

Hershkovitz, P. 1977. Living New World Monkeys (Platyrrhini) . Chicago: University of Chicago Press.

Heymann, E., M. Vasquez. 2001. Crested Eagle (Morphnus guianensis) Predation on Infant Tamarins (Saguinus mystax and Saguinus fuscicollis, Callitrichinae). International Journal of Primatology , 72: 301-303.

Rowe, N. 1996. The Pictorial Guide to the Living Primates . East Hampton, New York: Pogonias Press.

de la Torre, S., F. Cornejo. 2008. "IUCN 2008 Red List - Saguinus Tripartitus" (On-line). Accessed March 27, 2009 at http://www.iucnredlist.org/details/19824 .