Red Uakari

Scientific name	Cacajao calvus ucayalii
Head-body length	54-57 cm
Tail length	15-16 cm
Body mass	2800-3500 g
Distribution	western Amazonia (south of Rio Amazonas between Rio Ucayali and Rio Yavarí)
Habitat	tropical rain forest of terra-firme type; seasonally in flooded forest and “aguajales” (swamps dominated by the palm Mauritia flexuosa)
Diet	seeds, fruits, flowers, arthropods
Social organization	very large groups of up to 150 individuals, probably organized into subgroups of 25-50 individuals consisting of one male-multiple female units
Mating system	polygyny? polygynandry?
Gestation length and infant care	gestation length not known; infant carried by mother
Social behavior	allogrooming probably the most frequent affiliative behavior
Communication	mainly through vocalizations and mimics
Home-range size	not exactly known; probably >10 km²
Interspecific relations	often associated with squirrel monkeys (Saimiri sciureus)
Predators	confirmed: harpy eagles