Separação de nicho entre grupos taxonômicos de frugívoros na Floresta Nacional do Amapá

Abstract

Frugivores are important seed dispersers in tropical forests, with frugivory being very wide between birds and mammals, and they can disperse their seeds through the feces, and through their body. Functional traits of fruits, seeds and trees can influence which frugivores they forage in the trees. Phenology is important to understand the reproduction and also the regeneration of plants, and can be influenced by temperature, rainfall, day length and dispersion syndromes. The study was carried out in the National Forest of Amapá, made in 5 permanent plots, where the identification of the trees by species and measurement of the Diameter at the Height of the Chest were done. Phenology was made in 942 trees, using the index of activity index, and the observation of frugivores by the tree-focal method, in 72 focal trees. Data on phenological structures were correlated with rainfall data, showing that the accumulation of 3 months of rain influences the formation of young leaves, floral buds and mature fruits. In the analyzed focal trees, 27.8% were visited by frugivores, with a higher visitation in August and September, coinciding with the greater availability of mature fruits in those months. Functional traits of the fruits, functional traits of the seed and functional traits of the tree were important to explain the size of the frugivore that visited the tree, if there is the consumption of seed, abundance of frugivores that visited the trees and the longer time of visit of piciformes in the tree. Rainfall data correlated with the phenological data show that the accumulated rainfall of 3 months influences the formation of young leaves, floral buds and mature fruits, indicating a great importance of rainfall in the formation of phenological structures. Attributes of fruits, seeds and trees show that they are essential characteristics to determine the size and abundance of frugivores will visit the tree, as well as if there is consumption of seed and determine which taxonomic group will stay in the tree longer. It was concluded that there is the niche separation between frugivores, where primates arrive after the birds to feed, avoiding competition for exploitation. There is no difference in the visitation of the different taxonomic groups in the visitation of the different stages of fruiting. Through network analysis, he saw that species are classified as moderately generalist to specialists, with few interactions between species, probably due to the low rate of visitation of frugivores