THE IMPACT OF SEED DISPERSAL BY BLACK AND GOLD HOWLER MONKEYS ON FOREST REGENERATION

BRAVO S. P.

ECOLOGICAL RESEARCH

SPRINGER TOKYO

Año: 2012 p. 311 - 321

0912-3814

In Neotropical humid forest the majority of trees species have seeds dispersed by vertebrates. Seed deposition by vertebrates is often spatially aggregated and a low per capita survival for seeds and seedlings is predicted. However, mortality factors could be saturated by high densites. I evaluated whether recruitment of saplings of species dispersed by black and gold howlers (Alouatta caraya) in latrines is higher than at control sites: (1) below parent trees, (2) in trees not used by monkeys to sleep, (3) randomly chosen sites within the forest, and determined whether howlers may influence current floristic composition of the Paraná River flooded forest. I recorded saplings several years old in the territories of five monkey groups. In total, I found four times more saplings in latrines than in the other areas, results suggest that latrines being recruitment foci for the majority of species but larger samples are required to confirm this. Frequency distribution of the diameter of tallest saplings of more abundant species reflected recruitment over time. I found saplings of more species growing in latrines than outside of them. Saplings higher than 1 meter of two species of laurels (Ocotea diopyrifolia and Nectandra megapotamica) and one species of Myrtaceae (Eugenia punicifolia) had higher densities in latrines than below parent trees. Results suggest that mortality factors were saturated in latrines and that sapling could be had a high growth rate in latrines. In relation to the influence on floristic composition E. burkartiana, an uncommon species in the forest, could increase in abundance as consequence of seed dispersal by howlers.