Long-term persistence of the large mammal lowland tapir is at risk in the largest Atlantic forest corridor

Abstract

Forest corridor has been considered the main strategy for maintaining gene flow between isolated populations, yet their effectivity is poorly tested. Assessing signatures of genetic variation loss, gene flow reduction and inbreeding may be helpful for conservation of the biodiversity that needs large continuous areas. Here we evaluated the genetic structure and diversity of the largest neotropical mammal, the lowland tapir (Tapirus terrestris), living in the largest Atlantic forest corridor in Brazil. We used fecal-derived DNA, genotyped nine polymorphic microsatellite loci of 75 tapirs, and quantified genetic differentiation, genetic diversity, and landscape resistance to gene flow. We found genetic differentiation between the inland and coastal populations, which may be explained by elevation. Expected heterozygosity ranged between 0.64 (inland population) and 0.78 (coastal population), and a small Ne was observed in both populations. We demonstrated that even large continuous rainforests are not totally permeable to the gene flow of large organisms. Our study also changes our perception about the pristine of continuous corridors and their role for long-term survival of large mammals, suggesting that tapir conservation efforts should be taken even for populations in the large protected areas.

Keywords

• Fecal-derived DNA
• Genetic diversity
• Gene flow
• Landscape genetics
• Genetic population structuring