The reproductive biology of the cotton-top tamarin (Saguinus oedipus oedipus) in Colombia

The cotton-top tamarin (Saguinus o. oedipus) is the most endangered primate in Colombia today. This species is endemic to the northwest region of Colombia, and its survival is currently plagued by the increasing rate of forest destruction. Today the current population of cotton-top tamarins in Colombia numbers less than 1,000 individuals. In an effort to conserve the cotton-top tamarin, the University of Wisconsin-Madison and INDERENA have embarked on a multi-disciplinary research program to study this species in Colombia. Since 1988, three troops of tamarins have been studied in a protected reserve in Colombia. The tamarins were trapped from the forest and the adult male of each group was fitted with a radio-transmitter. Each animal was marked for individual identification, blood samples and skin biopsies were taken for genetic and parasitic evaluation and then the animal was returned to the forest. All animals were found to be in good health and no pathogenic parasites were found.;Each group of tamarins in the forest contained several adult males and females, juveniles, and infants. There were often several animals unrelated to the breeding pair that were living in wild groups. Using an electrophoretic analysis, it was determined that these unrelated animals had emigrated from neighboring groups. Both males and females of various ages emigrated to nearby groups.;Females in wild groups of tamarins gave birth to twins once a year. In all but one case, there was only one reproductively active female in each group. Infants were carried by all groups members and there were no sex differences in the amount of time males and females carried the young. Infants born in natural environments did not differ in their rate of development from their captive counterparts.;Additional information was gathered on pair-bond formation and reproductive functioning in wild-caught captive animals. Females paired with pre-pubertal males did not exhibit ovulatory cycling. Only when females were paired with unrelated, adult males did normal reproductive functioning occur.;Given the high genetic variability, low infant and adult mortality, and good health of the cotton-top tamarins in this reserve, it appears that this population of tamarins has a good chance for recovery if protected reserves can be established.