Demographic loss, genetic structure and the conservation implications for Indian tigers

Abstract

India is home to approximately 60 per cent of the world's remaining wild tigers, a species that has declined in the last few centuries to occupy less than 7 per cent of its former geographical range. While Indian tiger numbers have somewhat stabilized in recent years, they remain low and populations are highly fragmented. Therefore, the application of evidence-based demographic and genetic management to enhance the remaining populations is a priority. In this context, and using genetic data from historical and modern tigers, we investigated anthropogenic impacts on genetic variation in Indian tigers using mitochondrial and nuclear genetic markers. We found a very high number of historical mitochondrial DNA variants, 93 per cent of which are not detected in modern populations. Population differentiation was higher in modern tigers. Simulations incorporating historical data support population decline, and suggest high population structure in extant populations. Decreased connectivity and habitat loss as a result of ongoing fragmentation in the Indian subcontinent has therefore resulted in a loss of genetic variants and increased genetic differentiation among tiger populations. These results highlight that anthropogenic fragmentation and species-specific demographic processes can interact to alter the partitioning of genetic variation over very short time scales. We conclude that ongoing strategies to maximize the size of some tiger populations, at the expense of losing others, is an inadequate conservation strategy, as it could result in a loss of genetic diversity that may be of adaptive significance for this emblematic species.

Mitogenome analysis reveals a complex phylogeographic relationship within the wild tiger population of Thailand

“…S2 in the Supplement). Thirty variable sites were identified in the whole mitogenome excluding the control region (21 C/T and 9 A/G nucleotide substitutions), and there were 22 new variable sites (11 in WEFCOM and 11 in Ti2) when comparing our results to other studies (Luo et al 2004, Driscoll et al 2009, Zhang et al 2011, Kitpipit et al 2012, Mondol et al 2013, Sun et al 2015, Xue et al 2015) (see Table S4 in the Supplement). The WEFCOM haplotype carried 1 Panthera tigris altaica-specific single nucleotide polymorphism (SNP; 14711A) as described by Luo et al (2004), whereas Ti2 contained no subspecies-specific SNPs.…”

Human mining activity across the ages determines the genetic structure of modern brown trout (Salmo trutta L.) populations

“…)—for example, through habitat loss and fragmentation (Mondol et al. ); hunting pressure (González‐Porter et al. ); overfishing (Allendorf et al.…”

Islands within islands: two montane palaeo‐endemic birds impacted by recent anthropogenic fragmentation

“…; Mondol et al . ) across landscape features such as roads (Keller & Largiadèr ), production landscapes (Coulon et al . ; Lindsay et al .…”