Saguinus nigrifrons
Creators: name: Russell A. Mittermeier
name: Anthony B. Rylands
name: Don E. Wilson
Publisher: name: Lynx Edicions
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Primates
Callitrichidae
Saguinus
Saguinus nigrifrons

description: 30.
Geoftroy’s Saddle-back Tamarin
Saguinus nigrifrons
French: Tamarin a front noir / German: Schwarzstirntamarin / Spanish: Tamarin de frente negra
Taxonomy. Hapale nigrifrons 1. Geoffroy Saint-Hilaire, 1850,
type locality unknown. Restricted by P. Hershkovitz in 1977 to the lower Rio Yavari.
Formerly considered a subspecies of S. fuscicollis. A molecular genetic analysis by C. Matauscheck and colleagues published in 2011 placed it in a distinct clade with S. fuscicollis, S. weddelli, S. melanoleucus, and the S. leucogenys specimens that they sampled south of the Rio Pachitea.
Monotypic.
Distribution. NE Peru, between the rios Amazonas and Yavari, to the right bank of the rios Ucayali and Tapiche as far as the Rio Blanco (upstream of the Rio Ucayali along both sides of the river, to the S of the Rio Blanco,it is replaced by S. illigeri), but it appears again on the right bank of the Rio Ucayali at the headwaters of the Rio Tapiche, a left bank tributary of the Rio Blanco, probably extending E as far as the Rio Yavari, on the border with Brazil.
Descriptive notes. Head—body c.21 cm,tail ¢.32 cm; weight mean 366 g (n =50). At the Rio Blanco, Peru, mean weight of 33 adult males was 412-8 + 25-7 g, with a range of 365—482-5 g. Weights of 15 pregnant and lactating females did not differ from weights of males, averaging 411-7 + 47-6 g but with a greater range of 327-535-2 g. The black fur of the forehead and sides of the head of Geoffroy’s Saddle-back Tamarins contrasts sharply with the predominantly buffy-orange agouti of the crown, extending to the mantle. Facial skin is black, and there are short gray hairs surrounding the mouth and sides of the nostrils. Outer sides of upper arms are darker than the mantle, and forearms and inner parts of arms are blackish. The saddle is well defined, striated, or marbled black, grayish, or buffy. The rump and thighs are reddish orange, similar to the mantle, and upper surfaces of hands and feet have black hairs. The chest is dark brown to black with occasional orange or reddish hairs. The tail is black, exceptfor the base, which is rufous. External genitalia are pigmented black.
Habitat. Tall and secondary lowland rainforest, with a preference for dense vegetation in secondary forest, tree falls, and edge habitat. Geoffroy’s Saddle-back Tamarin has been the subject of a numberofstudies in the wild: on the left (south) bank of the Rio Blanco, a tributary of the Rio Tahuayo (in turn a tributary of the Rio Amazonas, a little upstream from Iquitos) by M. Ramirez, M. Norconk, and P. Garber (Estacion Biologica Quebrada Blanco 1) and on the right (north) bank of the Rio Blanco by R. Castro, T. Fang, and E. Heymann and colleagues (Estacion Biologica Quebrada Blanco 2).
Food and Feeding. Diets of Geoffroy’s Saddle-back Tamarins consist mainly of fruits, notably from the families Sapotaceae, Urticaceae (Cecropia, Pourouma), Moraceae, and Fabaceae (Inga); gums from a wide range of species but mainly of Parkia (Fabaceae); and small animal prey, mainly large grasshoppers but also spiders and small vertebrates such as lizards and frogs. One study at Quebrada Blanco, estimated that 59-8% of the diet was fruit pulp, 17% pod exudate (gum) from P. panurensis (Fabaceae), 13-3% gum readily exuded from tree trunks, 4-4% nectar, and 5-8% animal prey. In all, 124 plant species were exploited for food. Fruits eaten are largely drupes or arils of single or large number of small seeds. They are taken into the mouth whole, and the fibrous parts are spat out, either with seeds or alone. Drier mealy pulp is scraped off, and seeds are usually dropped. Geoffroy’s Saddle-back Tamarins are important seed dispersers. Seeds of 81 species are ingested and dispersed, including Parkia seeds swallowed when they eat the copious gum of the seed pods. Seeds from Anomospermum grandifolium (Menispermaceae) were most dispersed by Geoffroy’s Saddle-back Tamarins, occurring in 14:6% of 1699 dispersal events (i.e. number of times at least one seed of any of the 81 species was found in 1376 faecal samples). Seeds from Parkia were ranked second, occurring in 13-7% of the dispersal events. Fruit consumption drops slightly during the dry season, but fruit provided a higher percentage of the diet of Geoffroy’s Saddle-back Tamarins throughout the year than has been recorded for other saddle-back tamarins (e.g. Weddell’s Saddle-back Tamarin, S. weddelli, in the Manu National Park and Biosphere Reserve, Peru). Tree species tend to provide fruit synchronously and produce only small amounts of ripe fruit each day. A 14-month study, specifically examining consumption of gum and its nutritional importance, estimated that it contributed 21-2% of the plant part of the diet. Geoffroy’s Saddle-back Tamarins took gum from 84 individual plants of 17 species, the most important being Parkia nitida that provided gum from its capitula (dense, flat clusters of small flowers), seed pods, and trunk. Other important gum-providing species included P. igneiflora, Sloanea floribunda (Elacocarpaceae), Peltogyne altissima (Fabaceae), and an unidentified liana (that accounted for 18% of the exudate eaten by the tamarins). Both gums and nectar, especially from the flowers of Symphonia globulifera (Guttiferae), are important food sources during the dry season months ofJuly, August, and September. As is typical of all saddle-back tamarins, Geoffroy’s Saddle-back Tamarins forage for animal prey mostly on vertical substrata (trunks and lianas) in crevices and knot holes, mostly (68% of the time) at heights below 5 m and occasionally stalking and picking through leaf litter on the ground. Large orthopterans are preferred prey. Geoffroy’s Saddleback Tamarin will catch and eat Proscopiidae (stick grasshoppers), Romaleidae (lubber grasshoppers), especially Tettigoniidae (katydids, including five of its subfamilies), and Gryllacrididae (raspy and camel crickets). They also eat praying mantises (Mantodea, Mantidae), giant cockroaches (Blattodea, Blaberidae), lepidoptera, stick insects, cicadas, weevils, spiders, spider eggs, and scorpions. Their foraging techniques and the places they search are notably distinct from those of the middle to lower canopy, foliage-foraging “Spix’s Mustached Tamarins” (S. mystax mystax), with which they associate. Both mustached and saddle-back tamarins forage in (and drink water from) bromeliads. Studies of prey-capture comparing Spix’s Mustached and Geoffroy’s Saddle-back tamarins found that overlap in prey species was minimal. In one study, only three of the 35 species identified were eaten by both primates —an overlap of only 9-4%. In a second study, overlap was higher at 34%; 31 of 62 prey species that could be identified were eaten only by Geoffroy’s Saddle-back Tamarin, ten were eaten only by Spix’s Mustached Tamarin, and 21 were eaten by both primates. The two primates differ in their foraging techniques when seeking animal prey. Geoffroy’s Saddle-back Tamarins take larger and brownerprey, foraging in dark refuges; however, they benefit from green insects that fly or fall to the ground, flushed by Spix’s Mustached Tamarins foraging above them. Spix’s Mustached Tamarins forage in the foliage and find and eat generally smaller and greener insects. Vertebrate prey include frogs (Osteocephalus and Phyllomedusa: Hylidae) and reptiles, including Anolis (Iguanidae), Kentropyx (Teiidae), Mabuya (Scincidae), and Norops (Polychrotidae), mostly taken at heights below 10 m above the ground. A comparison of sympatric Spix’s Mustached and Geoffroy’s Saddle-back tamarins found that the former caught more tree frogs and latter more reptiles, as would be expected from their different foraging techniques. Nestling birds are eaten very occasionally.
Breeding. There is no specific information available for this species, but aspects of reproduction and breeding are undoubtedly those of saddle-back tamarins in general. Ovarian cycles last 26 days. Gestation is 145-152 days, with interbirth intervals as short as six months. Females mature at about three months. Births can occur throughout the year but peak from November to February in the early to middle wet season. Infanticide was once observed in a group of Geoffroy’s Saddle-back Tamarins at the Quebrada Blanco—a case of a mother killing her newborn that had fallen several times on the day it was born and may have been wounded or born debilitated, with little likelihood of survival.
Activity patterns. Groups of Geoffroy’s Saddle-back Tamarin are active for c.10-12 hours/day, beginning at ¢.06:00 h and entering sleeping sites at ¢.15:30-17:25 h. Foraging for animal prey takes up 15-23% oftheir day, feeding c.13%, traveling c.25%, and resting c.42%. Five types of sleeping sites have been identified: palm crowns ofJessenia bataua (Arecaceae) (most frequent); tree hollows (second most frequent); dense, tangled vegetation formed by epiphytic growth and vines; crotches of branches; and horizontal branches in the open—all mostly at 6-15 m above the ground.
Movements, Home range and Social organization. Group sizes of Geoffroy’s Saddleback Tamarins are 3-10 individuals, with an average of 5-8 ind/group, excluding 1-2 dependent infants. At Jenaro Herrera on the east bank of the Rio Ucayali, six groups averaged 6 ind/km* (range 3-6). In 62 groups counted at three other localities (Rio Maniti, Rio Tahuayo, and Rio Tapiche), average number of adults was 3-2 ind/group, with those besides the reproductive pair usually being males. Females leave their natal group at an earlier age than males. Geoffroy’s Saddle-back Tamarins at Quebrada Blanco occupy home ranges of ¢.40 ha, which overlap with other neighboring groups, and they travel c.1845 m/day. Encounters between groups are characterized by vigilance, vocal battles, chases, and physical combat, with both males and females participating. Aggressive behavior is coordinated among group members and directed mainly toward others of the same sex. Usually the group battles last ¢.25 minutes, but they can persist for as long as two hours. These encounters were usually at the locations of important feeding trees, and boundary areas not associated with these feeding trees were rarely defended. Success in defending the feeding tree was related to the size of the group. Geoffroy’s Saddle-back Tamarins form mixed-species groups with Spix’s Mustached Tamarins. They sleep in separate sites but join up in the morning and spend ¢.82% of their time traveling together—Geoffroy’s Saddle-back Tamarins mostly in the understory and Spix’s Mustached Tamarins mostly in the middle and lower canopy. These two primates have minimal social interactions, with about one interaction noted for every five hours of observation. Most interactions were agonistic, with the dominant Spix’s Mustached Tamarin displacing, threatening, and chasing away Geoffroy’s Saddle-back Tamarin from food sources, particularly when the canopy and number of available ripe fruits were small. The two species are known to groom each other in captivity, but this is evidently rare in wild groups. Geoftroy’s Saddle-back and Spix’s Mustached tamarins at the Quebrada Blanco respond to their respective alarm calls, which are given at a rate of about one every two hours. Birds that cause alarm include vultures, forest-falcons (Micrastur), black-collared hawks (Busarellus nigricollis), double-toothed kites (Harpagus bidentatus), smooth-billed anis (Crotophaga ani), herons, yellow-rumped caciques (Cacicus cela), toucans (Ramphastos) and parrots. Double-toothed kites are insectivorous, capturing their prey on the wing, and they tend to follow monkey groups, including capuchin monkeys (Cebus and Sapajus), squirrel monkeys (Saimiri), and tamarins, evidently taking advantage of insects flushed as the primates forage—cicadas in particularly at certain times of the year. Doubletoothed kites may follow groups of tamarins for more than two hours and are generally ignored; however, sometimes tamarins attempt to drive off a kite, and when it takes flight, the tamarins emit alarm calls. The rate of these alarm calls increases whenever kites follow tamarins. Similar but briefer associations have been observed with whitefronted nunbirds (Monasa morphoeus) and great jacamars (Jacamerops aureus). In most cases, alarms resulted in the tamarins moving down in the forest canopy or moving fast from the periphery of a tree to its trunk, but an (unsuccessful) attack by an ornate hawk-eagle (Spizaetus ornatus) caused the tamarins, exposed when feeding in the forest canopy, to literally fall out of the tree. The Guiana crested eagle (Morphnus guianensis) and the slate-colored hawk (Leucopternis schistacea) have been recorded as predators of Geoffroy’s Saddle-back and Spix’s Mustached tamarins at the Quebrada Blanco. After a predator attack, both species remain nervous for several days, and rates of alarm calling are higher than usual; they also spend more time than is typical in the lower levels of the forest canopy. A group of Geoffroy’s Saddle-back Tamarins was seen to approach and mob (giving a specific trill call) two mating garden tree boas (Corallus hortulanus enydris, Boidae), hanging from a liana; some individuals going as close as 1-5-2 m. Densities range from 1-5 groups/km? or 10-5 ind/km? at Santa Cecilia, Rio Maniti, to 5-6 groups/km* or 33-7 ind/km?* at Jenaro Herrera on the east bank of the Rio Ucayali, to a high of 10 groups/km?® or 60 ind/km? at Paucarillo on the Rio Orosa. Density at the Quebrada Blanco, Rio Tahuayo, in 1984 was 28-3 ind/km? or 4-7 groups/km?.
Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red Last (as S. fuscicollis nigrifrons). Geoffroy’s Saddle-back Tamarin is restricted to the Peruvian Amazon and reported to be common. It occurs in ACR Comunal Tamshiyacu-Tahuayo but not in any strictly protected area.
Bibliography. Aquino (1990), Aquino & Encarnacion (1994b), Bartecki & Heymann (1987, 1990), Castro (1991), Castro & Soini (1977), Fang (1990), Garber (1986, 1988a, 1988b, 1989, 1991, 1992), Garber & Teaford (1986), Glander et al. (1984), Hershkovitz (1966, 1977), Heymann (1990a, 1990b, 1992a, 1992b, 1995b, 1997, 2001), Heymann & Buchanan-Smith (2000), Heymann et al. (2000), Knogge & Heymann (2003), Lledo-Ferrer et al. (2009), Matauschek et al. (2011), Nickle & Heymann (1996), Norconk (1990), Oversluijs & Heymann (2001), Smith (1997, 2000a, 2000b), Smith, Buchanan-Smith et al. (2003), Smith, Knogge et al. (2007), Snowdon & Soini (1988), Soini (1990a, 1990b), Soini & Céppula (1981), Soini & de Soini (1986), Soini et al. (1989), Tapia et al. (1990), Tirado, Franke et al. (2003), Tirado, Knogge & Heymann (2000).
description: Published as part of Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Callitrichiade, pp. 262-346 in Handbook of the Mammals of the World – Volume 3 Primates, Barcelona :Lynx Edicions on pages 326-327, DOI: 10.5281/zenodo.5730714