Project Update: May 2005

This research is the first to assess the fate of seeds dispersed by golden-lion-tamarins (Leontopithecus rosalia) in the União Biological Reserve and considers both the survivorship and establishment of seedlings from golden-lion-tamarin feces.

Two groups of golden lion tamarins were studied from the time they left sleeping sites until the end of the day for a duration of 787.2 hours. Seeds from both fruits and feces were collected to study dispersion processes. Tamarins may be considered an efficient disperser due to choice of defacation sites; 88.7% of seeds were defecated in an appropriate habitat for germination. Dispersion through long distances may help pioneer trees invade forest gaps where densities of adults are very low (Fleming & Williams, 1990), and tamarins defecated seeds as far as 748 meters from parental trees (average distance = 110,17 meters).

Golden lion tamarins preferentially exploit some fruit species that occur in low percentages over some highly abundant species . To date 54% of control seeds (from fruits or seeds with pulp) and 44.3% of treated seeds (from feces or spit out) germinated, but this does not represent a significant difference. A total of 22 species of seeds germinated, of which 20 species became seedlings. The results are consistent with literature suggesting that the majority of seeds defecated by primates disappear on floors of the Tropical Forest. These seeds may be predated or dispersed to other locations by secondary dispersers. These locations may be more suitable for establishment and survival than the original location in which they were dispersed by tamarins. Additional results indicate that golden lion tamarins are good dispersers in Atlantic Forest, including: the distance and habitat of dispersion; quantity of dispersed seeds; large home ranges; and others.

The Golden-Lion-Tamarin Association (AMLD) proposes the following to promote the specie's conservation in the next years: planting of forested corridors and linking small patches where isolated populations of tamarins are located in order to eliminate genetic isolation. During the study period two groups of golden lion tamarins consumed 88 fruit species from at least 17 families. Understanding the golden-lion-tamarin's role as a seed disperser will assist in making informed decisions about the plant species used in biological corridors and may supply data to implement seed banks and a seedling vivarium in the future.