The emperor tamarin (Saguinus imperator) is a species of tamarin monkey allegedly named for its beard's resemblance to that of the German emperor Wilhelm II. It lives in the north Brazilian states of Acre and Amazonas and the southwest Amazon Basin, in east Peru, north Bolivia.
The fur of the emperor tamarin is predominantly grey colored, with yellowish speckles on its chest. The hands and feet are black and the tail is brown. Outstanding is its long, white beard, which extends to both sides beyond the shoulders. The animal reaches a length of , plus a long tail. It weighs approximately .
Physical description
There are claws on each of the animal's toes and fingers, aside from its big toe, which has a nail. While it has a definitive long mustache, it also has almost inconspicuous white hairs on its chin. The hair on its chest and belly are a mixture of red, orange, and white hairs. On its back, the fur is dark brown. The inner side of its arms and legs are an orange-like color.
They are very small, compared to most other primates. Using their claws, they cling to tree branches, maintaining a consistent verticality in the jungle environment. To navigate their lush environment, which typically is in rainforests, they leap and move quickly through trees, rarely touching the forest floor.
Subspecies
Two subspecies are currently recognized, the black-chinned emperor tamarin (Saguinus imperator imperator) and the bearded emperor tamarin (Saguinus imperator subgrisecens). Of the two subspecies, S. i. subgriscens is more varied in color on its chest, belly, and arms. Also, in addition to its long white mustache, this subspecies has a prominent white-haired beard, unlike S. i. imperator, which merely has faint black whiskers upon its chin.
Aside from these slight variations in color and visually-striking beards, both subspecies essentially have the same body structure.
Habitat
Emperor tamarins occur mostly in Amazonian lowland and lower mountain rain forests, as well as remnant, primary, and secondary forests.Buchanan-Smith H.M, Hardie SM, Caceres C, Prescott M.J 2000. Distribution and Forest Utilization of Saguinus and Other Primates of the Pando Department, Northern Bolivia. Journal of Primatology 21:353-379 Amazonian lowland holds an abundance of water during high sea level due to the flooding by nearby water sources. This contributes to a very humid, tropical climate to occur year-round.Irion G., Muller J., Nunes de Mello J., Junk W.J. 1995. Quaternary geoglogy of Amazonian lowland. Geo-Marine Letters 15:172-178 The lower montane forests Emperor tamarins are primarily found in are considered tropical and moist with an abundance of vegetation. During the dry season, flowering peaks and in the wet season, flowering decreases, affecting the diets of the Emperor tamarins.Jackson J.F. 1978. Seasonality of Flowering and Leaf-Fall in a Brazilian Subtropical Lower Montane Moist Forest. Biotropica 10:38-42 Many Emperor tamarins are found in Amazonian secondary forests, which account for 40% of the forest area. Secondary forests appear to accumulate woody plant species at a relatively rapid rate but the mechanisms involved are complex and no clear pattern emerged. This process helped grow the trees in which Emperor tamarins primarily reside in when found in secondary forests.Brown S. and Lugo A. 1990. Tropical Secondary Forests. Journal of Tropical Ecology 6:1-32 The average size of the group tamarins live in is two to eight individuals, but it can range from four to eighteen. They reside in the form of an extended family group, usually with only one breeding female. The groups they live in usually only consist of Emperor tamarins, but occasionally can also include saddle-back tamarins considering their food scavenging groups often join together. This is due to the fact Emperor tamarins tend to stay higher in the canopy than , and saddle-back tamarins usually stay below 10 metres.
Emperor tamarins consume a wide range of specimens in their daily dietary routine. They eat fruits and flowers, many of which are readily available due to their flourishing vegetational habitats. They also eat the exudes of plants such as gums and saps, easily gouged from the trees they are living in. Many also choose to consume animal prey, such as insects and frogs, depending upon what type of forest they are located in. Emperor tamarins have been reported to engage in mixed species associations with Weddell's saddle-back tamarins (S. fuscicollis weddelli), spending up to 20% of their day foraging in these mixed species troops. Emperor tamarin society is based on a dominance hierarchy led by a dominant female and her mate. It is the dominant emperor tamarins who form these foraging troops, forming these mixed species groups is beneficial to the emperor tamarins and their ability to find quality food resources. Some speculated at one point that females of the species were the primary scavengers of food, specifically fruit and flowers, because of their enhanced abilities over the males in the form of stronger visual cues. Upon research, it was found that males and females possess the same abilities to locate food patches. Though it does not discriminate between the two species, females do tend to be the more dominant hunters, which led to the speculation.Dominy N.J., Garber P.A., Bicca-Marques J.C., de Azevedo-Lopes, M.A. 2003. Do female tamarins use visual cues to detect fruit rewards more successfully than do males? Animal Behaviour 66:829-837 Weddell's saddle-back tamarins are better and faster at locating food resources. S. fuscicollis are a smaller bodied species of tamarins and are able to move fast through the canopy, saddle-back tamarins often arrive to the food resources before the emperor tamarins. The emperor tamarins follow the saddle-back tamarins to food patches using their larger size to intimidate the feeding Weddell's saddle-back tamarins into leaving the feeding tree. This foraging strategy is beneficial to both species, the mixed species troops provide more vigilance for predator protection. Observations of tamarins foraging in mixed species troops using feeding platforms and monitoring fruiting trees show that these troops spend less time foraging in smaller patches of fruiting trees with limited amounts of fruiting resources.Bicca-Marques J.C and Garber P.A. 2003. Experimental field study of relative costs and benefits to wild tamarins (Saguinus imperator and S. fuscicollis) of exploiting contestable food patches as sing- and mixed- species troops. American Journal of Primatology 60:139-153
Reproduction and infant care
The age of first reproduction in emperor tamarins is around 16–20 months old, with a gestation period of up to 6 months.Jones, K.E., Bielby, J., Cardillo, M., Fritz, S.A., O'Dell, J., Orme, C.D.L., Safi, K., Sechrest, W., Boakes, E.H., Carbone, C., Connolly, C., Cutts, M.J., Foster, J.K., Grenyer, R., Habib, M.Plaster, C.A., Price, S.A., Rigby, E.A., Rist, J., Teacher, A., BinindaEmonds, O.R.P., Gittleman, J.L., Mace, G.M., Purvis, A., Michener, W.K., 2009.PanTHERIA: a species-level database of life history, ecology, and geography of extant and recently extinct mammals. Ecology 90, 2648 Tamarins are seasonal breeders. Breeding is based around food availability. Most births occur during the wet season when food resources are in abundance.
Tamarin species were once thought to be a monogamous species, but observations of emperor tamarins in the wild show that they have a polyandrous mating system, with one dominant female mating with multiple males. This mating system works to ensure paternal investment in offspring. If a female mates with multiple males and give birth to a litter, males are more likely to invest because of the possibility that one of the infants will carry their genes onto the next generation. Due to high rates of twinning or multiple births in Emperor tamarins, parental care and paternal investment is important to infant survival. Previously the only knowledge of tamarin infant care came from captive studies on cotton-top tamarins (S. oedipus), which demonstrated that infant survival is dependent on helpers. Helpers are either older female offspring of the dominant female that have remained in their natal group or the males that most frequently interact with the dominant female. Infant carrying has a high energetic cost due to the relatively large fetal weight of infants to the weight of adults. Helpers provide the extra support to remove some of the cost of caring for multiple infants. Male emperor tamarins have been observed to spend the most time with infants, often carrying both infants while the dominant female forages. Male emperor tamarins are reported to be more observant of the infants and more protective. For example, they are known to react faster to infant distress calls than females.
Infant mortality in the wild is at its highest during weeks 5–15 of their lives, when they begin to move around and explore on their own, this is because one of the greatest threats to infant survival is falling from the canopy.Windfelder T.L. 2000. Observations on the birth and subsequent care of offspring by a lone pair of wild emperor tamarins (Saguinus imperator). American Journal of Primatology. 52:107-113
Distribution
The emperor tamarin can be found in Brazil; places in Peru and Bolivia that are parts of the southwest Amazon Basin; east of the upper Purus river; between the Purus river and Rio Acre; east of the upper Juruá River to the Tarauacá River and Jurupari River; west to the Urubamba River and Inajá River; and south of Tahuamanu River.Bairrao Ruvio E. 2010. Husbandry Guidelines for Callitrichidae. EAZA. 2nd Edition. 1-218.
According to Buchanan's research, the subspecies of S. imperator, S. i. imperator, are rarely found in Los Campos and Buena Vista, which are located near the left bank of the Rio Acre; and in the banks of the Purus River and Eiru River.
Lastly, according to Buchanan and Bairrao, the subspecies, S. i. subgrisescens, can be found on the upper banks of the Juruá River; south of the Tahuamanú river and along the banks of the Muyumanu river.
Behavior Emperor tamarins behave actively, rapidly, gracefully, gregariously, and playfully in the wild. In captivity the tamarins are very social and interactive with humans. A study by Knox, Kerry L. and Donald Stone Sade of the social behavior of emperor tamarins in captivity found that tamarin colonies behave agonistically according to seniority. There is an agonistic network where each component along a continuum from strongly dominant individuals interaction with strongly subordinate individuals. In the interactions the tamarins usually communicate threat and submission. The aggression is more frequently among individuals of the same sex, most frequently between juvenile males and juvenile males, between juvenile females and juvenile females and also between sexed twins. There are matrices of within family groups of emperor tamarins where a large proportion of the total number of agonistic interaction within a group occurs between pairs of siblings from different litters. The dynamics of agonistic relations within a group is not just only for the status of the breeding pair but may also influence the allocation of reproductive effort. Family members other than the breeding female may suppress reproduction in adult daughters too. There are certain behaviors that were identified as dominant and some responses as subordinate.