Avaliação do processo de predação natural em seis espécies de palmeiras do estuário amazônico.

Abstract

the natural predation process can be characterized as a biological event that is restricted to a group of vertebrate or invertebrate animals that feed on the vegetative and reproductive structures of a plant population. This natural process may influence the effective size of plant populations and, consequently, provide variations in gene flow and genetic structure. The present work aims to evaluate the natural predation process in six species of native palms from the Amazon estuary: Astrocaryum murumuru Mart; Bactris major Mart; Bactris minor Mart; Desmoncus sp; Geonoma sp; Scheelea sp. The experiment was set up at the experimental base of the Emílio Goeldi Museum, located at Ilha do Combu, Municipality of Acará-Pa. The methodology used was to mark 5 plots of 25m2 and 500 seeds per species. The seed predation process was monitored weekly during the period from September 1993 to March 1994. The results showed that the predation rate and seed transport were: B. minor (46.4% and 16.8%); Geonoma sp. (26.4% and 54.4%); Scheelea sp. (18.2% and 25.2%); Desmoncus sp. (7.8% and 68.6%); B. major Mart. (3.0% and 71.2%); A. murumuru Mart. (6.8% and 28.4%). The main predatory agents identified were coleoptera, diptera and rodents. The forms of predation observed on fruits and seeds were consumption of the pulp, holes in the mesocarp and damage to the endosperm. Some insects oviposit inside the seeds that serve as food substrate for the larvae.