Occurs in lowland and sub-montane forest, and dry forest patches in desert scrub (the north of its range in the Jequitinonha valley) (Rylands et al. 1988; Passamani 1996). White-faced marmoset inhabits a great variety of habitats, including dense forest, semideciduous forest of the Atlantic Forest biome and deciduous forest in the Caatinga biome (the northern distribution reachs the Jequitinhonha Valley) (Rylands et al. 1988, Passamani 1996). The taxon is not restricted to primary habitats (Rylands and Mendes 2008a), and is tolerant to changes / disturbances in the environment, occurring in forest fragments immersed in eucalyptus monoculture matrix (Passamani 1996, 1998, Passamani and Rylands 2000a,b). Therefore, it can be considered a species very adapted to antropic environments (Rylands and Mendes 2008a).
Marmosets and tamarins are distinguished from the other monkeys of the New World by their small size, modified claws rather than nails on all digits except the big toe, the presence of two as opposed to three molar teeth in either side of each jaw, and by the occurrence of twin births. They eat fruits, flowers, nectar, plant exudates (gums, saps, latex) and animal prey (including frogs, snails, lizards, spiders and insects). Marmosets have morphological and behavioural adaptations for gouging trees trunks, branches and vines of certain species to stimulate the flow of gum, which they eat, and in some species form a notable component of the diet (Coimbra-Filho 1972, Rylands 1984). They live in extended family groups of between four and 15 individuals. Generally, only one female per group breeds during a particular breeding season. The groups defend home ranges 10-40 ha, the size depending on availability and distribution of foods and second-growth patches. Passamani and Rylands (2000b) recorded a home range of 23.3 ha, in a forest fragment of 119 ha surrounded by a Eucalyptus plantation, in the state of Espírito Santo. While Abbehusen et al. (2005) have recorded a home range of 34.4 ha in the Vera Cruz Station, Porto Seguro, BA; and 22.25 ha at the same place in further occasion (Abbehusen et al. 2007).
Passamani (1996, 1998, Passamani and Rylands 2000a,b) studied the behaviour and ecology of a group of five C. geoffroyi in a forest fragment amongst Eucalyptus plantations of Aracruz Cellulose Cia., in Espirito Santo.
Size:Males 359 g (n=46) (Rosenberger 1992; Bicca Marques and Silva 2012).Females: 300-450 g (Bicca Marques and Silva 2012).

Geoffroy’s Marmoset occurs in the state of Espírito Santo and the forested eastern and north-eastern part of Minas Gerais, north as far as the Rios Jequitinhonha and Araçuaí and south to near the state border of Espírito Santo and Rio de Janeiro (Ávila-Pires 1969, Hershkovitz 1977, Coimbra-Filho 1984, Rylands et al. 1988). The populations just south of the Rio Jequitinhonha resulted from animals released near its mouth, at Belmonte, around 1975 (Coimbra-Filho 1986c). From there it spread eastward, and today also occurs in gallery forests throughout the region of dry thorn scrub (caatinga) of the middle reaches of the river (Rylands et al. 1988). Vivo (1991) limits it to the east of the Serra do Espinhaço in Minas Gerais. It has been recorded from the eastern slopes of Serra do Cipó, a southerly section of the Serra do Espinhaço range, at an altitude of 1,274 m (Oliveira et al. 2003). Hybrid populations of C. penicillata and C. geoffroyi have been observed in some parts of the Serra da Piedade along the Rio Piracicaba, affluent of the upper Rio Doce, where the Atlantic coastal forest gives way to the cerrado (Coimbra-Filho et al. 1993, Passamani et al. 1997). The range of C. geoffroyi overlaps with C. flaviceps (see below) in southern Espírito Santo (south of the Rio Doce) and south-eastern Minas Gerais. However, C. geoffroyi is generally restricted to lowland areas, below 500–700 m, and C. flaviceps to altitudes above 400–500 m (Coimbra-Filho 1971, Coimbra-Filho et al. 1981). Hershkovitz (1977) asserted that the highest recorded locality for C. geoffroyi is Santa Teresa, 659 m asl, but Mendes (1993, 1997a) has observed mixed bands of C. geoffroyi and C. flaviceps at altitudes of 800 m. Hybrid populations have been recorded for intermediate elevations (Mendes 1993, 1997a). It is urgent to survey some important sites such as the Monte Pascoal National Park, because its occurrence is uncertain in this locality. The extent of occurrence of the species is greater than 20,000 km² and it seems that its area of occupancy is greater than 2,000km².

This species occurs in a number of protected areas:

Minas Gerais
Serra do Cipo National Park (33,800 ha), Minas Gerais (Oliveira et al. 2003)
Fazenda Córrego de Areia Reserve (60 ha) (privately owned)

Espirito Santo
Córrego Grande Biological Reserve (1,504 ha) (Mendes 1991, Chiarello 1999)
Córrego do Veado Biological Reserve (2,392 ha) (Mendes 1991, Chiarello 1999)
Sooretama Biological Reserve (27,943 ha) (Mendes 1991, Chiarello 1999)
Comboios Biological Reserve (833 ha) (Mendes 1991)
Duas Bocas State Reserve (2,910 ha) (Mendes 1991)
Linhares Forest Reserve (21,787 ha) (Mendes 1991, Chiarello 1999))
Goitacazes Forest Reserve (1,400 ha) (Mendes 1991)
Santa Lucia Biological Station (350 ha) (Mendes 1991)
Fazenda São Joaquim Reserve (Klabin Reserve) (1,505 ha)(Mendes 1991)
Its occurrence in the Monte Pascoal National Park is in some doubt, and Oliver and Santos (1991) reported that C. jacchus had possibly been introduced there.


Bahia
Porto Seguro Forest Reserve (6,069 ha)
Pau Brasil Experimental Station (900 ha)
Gregório Bondar Experimental Station (710 ha)

Santa Catarina
Córrego Grande Ecological Park (21,3 ha) (Zago et al. 2007).

This species is listed on Appendix II of CITES.