Callithrix kuhliiWeid's black-tufted-ear marmoset

Geographic Range

Callithrix kuhlii (Weid’s black-tufted-ear marmoset) lives in Southwest Brazil, mainly in the coastal regions. (Rylands, 1993)


Weid’s black-tufted-ear marmosets live in a variety of forest types, particularly tropical and subtropical forests. These marmosets inhabit the lower part of the trees. It thrives in areas of dense vegetation and new growth. (Mittermeier, et al., 1988)

Physical Description

Weid’s marmosets are relatively small, weighing between 350 and 400 grams, or about 13 ounces. They are generally black with gray head pelage and have a distinctly ringed tail. There is an area of white around their cheeks and forehead, and they have black tufts of hair around their ears. They have nails that are claw-like and lack opposable thumbs. ("Marmosets and Tamarins", 2001; "Singapore Zoological Gardens Docents", 2000; Mittermeier, et al., 1988)

  • Range mass
    350 to 400 g
    12.33 to 14.10 oz


The dominant female of a group of C. kuhlii mates with several males. In this way, the father is not known, thus all the males help in caring for the infants after they are born. Actual mating has rarely been observed. However, males have been seen strutting around females with their backs arched and hair bristled. This behavior and the apparent pursuit of females lasts approximately 45 minutes. (Mittermeier, et al., 1988; Rylands, 1993)

Only the dominant female of the group breeds. Females reach reproductive maturity around 12-15 months of age and males at one year. The dominant female in the group is the only one who is allowed to breed since the investment for raising the young is so high, but this dominant status is always changing. The dominant female or her replacement enters into estrus 5-12 days after giving birth. Female Weid’s marmosets can give birth up to twice a year and young are always born in pairs. ("The Primata", 2003; Nunes, et al., 2001; Nunes, et al., 2000; Rylands, 1993)

  • Breeding interval
    twice yearly
  • Average number of offspring
  • Average gestation period
    4.5 months
  • Range weaning age
    4 to 6 months
  • Average time to independence
    12 months
  • Range age at sexual or reproductive maturity (female)
    12 to 15 months
  • Average age at sexual or reproductive maturity (male)
    12 months

Gestation of a pregnant female lasts about 4.5 months. She always gives birth to twins which comprise up to 25% of her body weight. She receives help raising the babies from the males and younger females of the group. The males help by carrying the babies while the mother goes to find food. Other members of the family may share food with the infants after they have been weaned. ("Singapore Zoological Gardens Docents", 2000; Mittermeier, et al., 1988; Nunes, et al., 2000; Rylands, 1993)

  • Parental Investment
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • male
      • female
    • protecting
      • male
      • female
  • pre-independence
    • provisioning
      • male
      • female
    • protecting
      • male
      • female
  • post-independence association with parents


These marmosets live about 10 years in the wild and have been known to live up to 16 years in captivity. ("Singapore Zoological Gardens Docents", 2000; "The Primata", 2003)

  • Range lifespan
    Status: wild
    10 (high) years
  • Range lifespan
    Status: captivity
    16 (high) years
  • Average lifespan
    Status: captivity
    20 years


Weid’s black-tufted-ear marmosets live in groups of about seven composed of many females and a few males, in an approximate ratio of two females for every one male. They are highly social and spend most of the day foraging and grooming. Everyone in the group helps to care for the infants that are born twice a year. Female babies grow up and become a part of the group while males generally leave when they reach sexual maturity, around a year after birth.

Callithrix kuhlii has a distinct "voice" much the same way that humans do. It uses specific vocalizations known as "phee calls" to identify itself to others in its group and to intruders.

Callithrix kuhlii moves through its area quadrupedally, but can leap from tree to tree. It travels between 830 and 1200m a day in search of food. These marmosets are sympatric with the tamarin Leontopithecus chysomelas, which travels with it and forages as well. These two species do not fight with one another because the marmosets forage in the middle and lower parts of the forest, while the tamarins forage in the upper canopy. Both of theses groups gain from this mutualism by having additional eyes above and below to watch for predators and receive early warning.

Weid’s marmosets mark their territory by rubbing secretions from their suprapubic gland onto an area. They do this by pressing the suprapubic pad on the object and pulling themselves along it with their arms. ("Singapore Zoological Gardens Docents", 2000; "The Primata", 2003; Mittermeier, et al., 1988; Nunes, et al., 2001; Ruskalis, et al., 2003; Rylands, 1993)

  • Average territory size
    100 m^2

Home Range

The territory of C. kuhlii is approximately 100 square meters, however, these marmosets can move up to 1200 m a day to forage. ("Singapore Zoological Gardens Docents", 2000; Mittermeier, et al., 1988)

Communication and Perception

Callithrix kuhlii communicate with one another using visual, tactile, olfactory and acoustic signals. These marmosets use visual signals to try to mate, they touch one another while they groom to form bonds, they leave scent trails to mark their territory and they call to one another, especially if danger is perceived. ("The Primata", 2003; Marroig, et al., 2004; Mittermeier, et al., 1988; Rylands, 1993)

Food Habits

Callithrix kuhlii feeds on fruit, flowers, nectar, seeds, insects, and spiders. Sap is a main staple in its diet and it has specialized teeth for gouging holes in tree bark.

  • Primary Diet
  • herbivore
    • eats sap or other plant foods
  • Animal Foods
  • insects
  • terrestrial non-insect arthropods
  • Plant Foods
  • seeds, grains, and nuts
  • fruit
  • nectar
  • flowers
  • sap or other plant fluids


The main predators of marmosets are harpy eagles: Harpia harpyja, hawks: Buteo albicaudatus, Asturina nitida, Buteo magnirostris, jaguar: Panthera onca, jaguarundi: Felis yagouaroundi, ocelot: Leopardus pardalis, and snakes: suborder Serpentes. Their main means of defense is speed or they may gang up on smaller predators and try to intimidate them into going away. ("Singapore Zoological Gardens Docents", 2000; "The Primata", 2003)

Ecosystem Roles

The holes made by gouging out tree bark provide sap for other animals. Marmosets play a role in pollination and seed dispersal as fruit and nectar are common components of their diet. They may travel extensively throughout their home range every day, pollinating many plants and dispersing seeds. They are also prey for many other species. ("Singapore Zoological Gardens Docents", 2000; Mittermeier, et al., 1988; Rylands, 1993)

  • Ecosystem Impact
  • disperses seeds
  • pollinates

Economic Importance for Humans: Positive

Weid’s marmosets have been a large commodity in the pet trade, especially in the United States until the U.S. prohibited its importation. It also can be used in biological and medical laboratories because it breeds easily and can be affected by some human diseases such as rubella and herpes. ("The Primata", 2003; Rylands, 1993)

  • Positive Impacts
  • pet trade
  • research and education

Economic Importance for Humans: Negative

There are no known adverse affects of C. khulii on humans.

Conservation Status

Callithrix kuhlii are not endangered, but their numbers are dwindling due to habitat destruction. ("Singapore Zoological Gardens Docents", 2000; Mittermeier, et al., 1988; Rylands, 1993)

Other Comments

Callithrix kuhlii was previously hypothesized to come from hybridization of Callithrix geoffroyi and Callithrix penicillata, however, new evidence shows that it is morphologically distinct from other marmosets. (Marroig, et al., 2004)


Matthew Wund (editor), University of Michigan-Ann Arbor.

Theresa Keeley (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.



living in the southern part of the New World. In other words, Central and South America.

World Map


uses sound to communicate


Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


uses smells or other chemicals to communicate

cooperative breeder

helpers provide assistance in raising young that are not their own

  1. active during the day, 2. lasting for one day.
dominance hierarchies

ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates


animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.


forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.


An animal that eats mainly plants or parts of plants.


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.


Referring to a mating system in which a female mates with several males during one breeding season (compare polygynous).


rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them


remains in the same area


reproduction that includes combining the genetic contribution of two individuals, a male and a female


associates with others of its species; forms social groups.


uses touch to communicate


Living on the ground.


defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


uses sight to communicate


reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year


2001. Marmosets and Tamarins. Pp. 678-695 in D Macdonald, ed. The New Encyclopedia of Mammals, Vol. 1, 2nd Edition. Oxford: Oxford University Press.

2000. "Singapore Zoological Gardens Docents" (On-line). Accessed March 29, 2004 at

2003. "The Primata" (On-line). Accessed March 29, 2004 at

Marroig, G., S. Cropp, J. Cheverud. 2004. Systematics and evolution of the jacchus group of marmosets. American Journal of Physical Anthropology, 123(1): 11-22.

Mittermeier, R., A. Rylands, A. Coimbra-Filho, G. Fonseca. 1988. Ecology and Behavior of Neotropical Primates. Washington D.C.: World Wildlife Fund.

Nunes, S., J. Fite, J. French. 2000. Variation in steroid hormones associated with infant care behaviour and experience in male marmosets. Animal Behaviour, 60: 857-865.

Nunes, S., J. Fite, K. Patera, J. French. 2001. Interactions among paternal behavior, steriod hormones and parental experience in male marmosets. Hormones and Behavior, 39: 70-82.

Ruskalis, M., J. Fite, J. French. 2003. Social Change Affects Vocal Structure in a Callitrichid Primate. Ethology, 109(4): 327-340.

Rylands, A. 1993. Marmosets and Tamarins. New York: Oxford University Press.