Diversidade local e influência da sazonalidade sobre taxocenoses de anfíbios e répteis na Reserva Extrativista Chico Mendes, Acre, Brasil

Abstract

Despite the high richness of amphibians and reptiles known for the southwestern portion of the Brazilian Amazon, the knowledge of these is punctual and few studies have evaluated the temporal variations in the occurrence and abundance of species. The goals of this study were to present the amphibians and reptiles assemblages in a locality of the Chico Mendes Extractive Reserve, verify which climate variables influence the temporal fluctuations in richness and abundance, and identify the main species of the amphibians and reptiles influenced by them. The study area is located in the Seringal Etelvi region, southwestern portion of the Reserve, municipality of Brasiléia, state of Acre. Data collection took place between October 2011 and September 2012, for 48 sampling days, using the methods of searches limited by time and pitfall traps. There were recorded 978 specimens of 31 amphibians and 54 reptiles. Higher richness and abundance of amphibians occurred during the rainy season, with the monthly abundance positively associated with the mean temperature. Only the abundance of reptiles was higher during the rainy period. However, both richness and abundance were positively associated with mean temperature. Four amphibians, Allobates gr. marchesianus, Hamptophryne boliviana (Parker, 1927), Boana geographica (Spix, 1824) and Rhinella marina (Linnaeus, 1758), and two reptiles, Kentropyx pelviceps Cope, 1868 and Norops fuscoauratus (D’Orbigny, 1837), had their monthly abundances positively associated with the mean temperature. The lizard Dactyloa punctata (Daudin, 1802) had the monthly abundance associated with precipitation. It was possible to verify the increase of richness and abundance of amphibians and reptiles during periods when the availability of resources is favorable for many species. Species can react differently to climatic variations, whereas others are sensitive to fluctuations, others seem answer easily or not reduce their abundances in periods theoretically unfavorable.