Collared titi causes them to give alarm peeps, probably because they must be especially alert to predators. A margay was detected alongside a dead collared titi during recent censuses on the Purité River in Colombia, although the monkey was not freshly killed. The local group was no longer observed after this. The collared titi is not considered to be endangered, but where there are many colonists this primate tends to disappear, due to deforestation. The species is commonly hunted and eaten by indigenous peoples or used as bait for hunting larger carnivores or for fishing; however, where there is plenty of forest
Collared titi is found west of the Río Purús to the Yavarí River. The collared titi is seen most frequently in well-developed, tall forest with a closed canopy, usually over terra firme, but not exclusively so. The species also enters extensive várzea forest, especially if the forest is tall and well-developed. Such várzea forest contrasts with the habitat needs of the coppery titi, which also uses várzea forest and more commonly so. But the coppery titi survives in low, vine-covered, "poor" forest where the collared titi is rarely found. It is also known from some gallery forest, north of the Vichada River,