Dusky titi monkeys occur in most forested parts of Brazil around the Amazon Basin, reaching into Colombia and Venezuela, around the headwaters of the Orinoco River. An inhabitant of densely vegetated areas, the dusky titi monkey often occurs in damp, waterlogged forest. It can move quite fast if necessary, but rarely does so. It generally stays within a fairly small area. They tend to live in the lower trees near riverbanks, often climbing down to the shrub plants near the ground to feed on fruit, leaves, birds’ eggs, and invertebrates. In periods of drought, these monkeys survive by eating figs, which are among the few forest fruits that are abundant in the dry season. As night falls, dusky titis climb higher into the trees to escape predators. Dusky titi monkeys have rounded heads and thick, soft coats and frequently adopt a characteristic posture, with the body hunched, limbs close together and tail hanging down.
These small monkeys are active during the day, waking up at dawn. During the night, they usually huddle together in nests, holding each other’s tails. Living in relatively open areas of forests and being active during the day exposes these titi monkeys to birds of prey - their major predators. The titi monkeys freeze, and rely on their colouration to blend into the background when such birds are sighted. Other monkeys, notably capuchins (Cebus species) may also attack them, especially when they are feeding on fruit.
Dusky titi monkeys exhibit a variety of fur colours, ranging from grey to red to gold. Their tails are long and bushy, but not prehensile. When resting, a pair of monkeys will entwine their tails together.
This species lives in family groups, each of which is dominated by a single adult pair. A baby titi monkey is quite large, so the male carries it for most of the time, only giving it to the female for suckling. This ensures that a higher percentage of the young survive than if the females were to raise them alone. When breeding, female titi monkeys will seek out more invertebrates, as a way of increasing their protein intake.
Distribution: Occurs in South America, with this particular species confined to Brazil, in forested areas ranging across the country to the south of the Amazon River.
Weight: 0.88 - 1.02 kg (1.9 - 2.2 lb).
Length: Around 73 cm (29 in) overall; tail is longer than the body.
Maturity: Around 2.5 years.
Gestation Period: Around 128 days.
Breeding: 1; weaning occurs at 15 - 21 months.
Diet: Mainly on fruit, but also young leaves and invertebrates.
Lifespan: Probably 20 years; up to 25 in captivity.
Small and well-spaced on the sides of the titi's head, the ears are inconspicuous.
The central area, from the eyes to the upper part of the chin, is dark and free of fur.
The feet are black, contrasting with the fur on the body.
The tail is quite long and well-covered with fur, but is not prehensile.
The timing of the dry and wet seasons can vary from year to year, so young titi monkeys may become soaked soon after birth.
These monkeys can move in a variety of ways, ranging from hopping to climbing. They may have a close relationship, grooming each other and entwining tails when resting.
Masked titi monkeys inhabit the mixed forests that grow along the Atlantic coast of Brazil south of the mouth of the Amazon. They prefer forests with a broken canopy, where enough light reaches the ground for a thick under storey (undergrowth layer) to grow. Masked titi monkeys live in widely distributed groups, with only a few monkeys occupying large areas of forest. The destruction of coastal forests has meant that the populations of this species are now small, isolated and increasingly vulnerable.
There are five subspecies of masked titi each with a differently coloured coat. Most have black foreheads and sideburn-like tufts around their dark faces. Their bodies have a range of grey or yellow-orange fur. The tail is not prehensile.
Like other titi monkey species, masked titis form monogamous pairs that mate for life. The male does the bulk of the carrying once the single young is produced, and he is responsible for nearly all of the parental care after weaning. Young masked titi monkeys stay with their parents for at least a couple of years, helping to raise their younger siblings.
Distribution: Atlantic coast of Brazil.
Habitat: Coastal forests.
Food: Fruit, insects, birds' eggs and mice.
Size: 31 - 42 cm (12 - 16.5 in); 0.97 - 1.65 kg (2.2 - 3.75 lb).
Breeding: Single young born between August and October.
Life span: 20 years.