Linking landscape to molecules: genetic analysis of tapir populations (Tapirus terrestris) of the Atlantic rainforest of São Paulo State

Abstract

Mammal populations, especially of medium and large-sized species, have been suffering significant reductions as a result of hunting, habitat loss and fragmentation induced by human economical development. The disruption of continuous environments, such as fragmentation, highways and agricultural areas, may cause serious consequences in the gene flow of mammalian species. Tapir (Tapirus terrestris) is one of the most aimed large-sized mammals for hunting and has suffered a drastic population reduction even in the continuous forests of the Atlantic rainforest. Two large areas of Atlantic Forest in São Paulo state (Southeast Brazil) probably contain the largest populations of this megaherbivore, Serra do Mar and Serra de Paranapiacaba. This project will investigate tapirs through non-invasive genetic analysis of faecal samples in two corridors: Serra do Mar Corridor (Santa Virgínia, Cunha, Picinguaba, Pedro de Toledo e Caraguatatuba Stations) and Serra de Paranapiacaba Corridor (Parque Estadual do Alto do Ribeira, PE Intervales, PE Carlos Botelho e PE Jacupiranga), besides the areas linking these two corridors (PE Jurupará e EE Jureia-Itatins), with the use of microsatellites markers. This study complements part of the Biota project entitled "Trophic cascades in a defaunated landscape: the Atlantic rainforest perspective" and results are intended for helping in the estimates of population minimun number and genetics diversity of these populations, besides mapping the individuals in the areas, verifying the movement pattern and gene flow of this important megaherbivore. Genetic data will be supplemented with landscape data aiming to verify the effects of the landscape structure on the distribution and movement of these animals. This project has already been initiated with the isolation of microsatellites markers. A total of 67,064 pb was sequenced and 18 microsatellites were identified, for 16 was possible the designing of primers. The loci characterization has been iniciated. This genetic investigation may provide valuable information since there is no data concerning the genetic diversity of T. terrestris that have an important function as seed dispersers and are considered vulnerable and suffer a great hunting pressure. Studies on biology, ecology and monitoring of the genetic variability of populations of these organisms are very important, because all scientific information has a strategic role not only in the management and conservation of the species, but also in the sustainability of the ecosystem studied.