Seed Dispersal by Woolly Monkeys in Cueva de los Guacharos National Park (Colombia): An Amazonian Primate Dispersing Montane Plants

Woolly monkeys (Lagothrix spp.) have been reported as efficient seed dispersers in Neotropical lowland forests. However, it is unknown whether these primates keep these mutualistic interactions in montane habitats, with plant communities that have a different evolutionary history. In this study, seed dispersal patterns (i.e., fruits consumption and dispersal at the individual and population levels) by mountain woolly monkeys are described. We evaluate the possible differences between juveniles and adults in the sizes of the seeds dispersed, and the relationship between the number and biomass of dispersed seeds, and the variation in fruit productivity per month. To achieve this, focal animal follows were performed for 5 days per month, during 11 months at the Cueva de Los Guacharos National Natural Park (Colombia). A total of 178 fecal samples were collected, for an average of three depositions per day, which contained 65,890 seeds from 29 plant species and 7 morphospecies. Six families were the most representative, with 67 % of the records. The most dispersed species in terms of biomass was Tapirira sp. (Anacardiaceae), while Cecropia spp. (Urticaceae) and Saurauia brachybotrys (Actinidaceae) were the most important in terms of the number of seeds dispersed. The size range for processed seeds varied between 0.75 and 20 mm in width. There were no statistical differences in the dispersed species between adults and juveniles; however, the maximum size of seeds dispersed by adult individuals (Tontelea sp, 20 mm) was higher than for juveniles (Tapirira sp., 12.9 mm). A positive relationship was found between the biomass of dispersed seeds and their availability. This may be explained by the fact that they show a generalist diet and an efficient role as seed dispersers. We conclude that, woolly monkeys play an important role in the dispersal of seeds from plant communities in Neotropical highlands, especially as most other large frugivorous primates are absent from these ecosystems.