Dataset Information

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.

SUBMITTER: Mondol S

PROVIDER: S-EPMC3673047 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

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

Mondol Samrat S Bruford Michael W MW Ramakrishnan Uma U

Proceedings. Biological sciences 20130515 1762

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 ...[more]

PMID: 23677341

Similar Datasets

Project description:Cost-effective use of limited conservation resources requires understanding which data most contribute to alleviating biodiversity declines. Interventions might reasonably prioritise life-cycle transitions with the greatest influence on population dynamics, yet some contributing vital rates are particularly challenging to document. This risks managers making decisions without sufficient empirical coverage of the spatiotemporal variation experienced by the species. Here, we aimed to explore whether the number of studies contributing estimates for a given life-stage transition aligns with that transition's demographic impact on population growth rate, λ. We parameterised a matrix population model using meta-analysis of vital rates for the common eider (Somateria mollissima), an increasingly threatened yet comparatively data-rich species of seaduck, for which some life stages are particularly problematic to study. Female common eiders exhibit intermittent breeding, with some established breeders skipping one or more years between breeding attempts. Our meta-analysis yielded a breeding propensity of 0.72, which we incorporated into our model with a discrete and reversible 'nonbreeder' stage (to which surviving adults transition with a probability of 0.28). The transitions between breeding and nonbreeding states had twice the influence on λ than fertility (summed matrix-element elasticities of 24% and 11%, respectively), whereas almost 15 times as many studies document components of fertility than breeding propensity (n = 103 and n = 7, respectively). The implications of such mismatches are complex because the motivations for feasible on-the-ground conservation actions may be different from what is needed to reduce uncertainty in population projections. Our workflow could form an early part of the toolkit informing future investment of finite resources, to avoid repeated disconnects between data needs and availability thwarting evidence-led conservation.

Project description:A heated debate has recently emerged between tiger farmers and conservationists about the potential consequences of lifting the ban on trade in farmed tiger products in China. This debate has caused unfounded speculation about the extent of the potential market for tiger products. To fill this knowledge gap, we surveyed 1880 residents from a total of six Chinese cities to understand Urban Chinese tiger consumption behavior, knowledge of trade issues and attitudes towards tiger conservation. We found that 43% of respondents had consumed some product alleged to contain tiger parts. Within this user-group, 71% said that they preferred wild products over farmed ones. The two predominant products used were tiger bone plasters (38%) and tiger bone wine (6.4%). 88% of respondents knew that it was illegal to buy or sell tiger products, and 93% agreed that a ban in trade of tiger parts was necessary to conserve wild tigers. These results indicate that while Urban Chinese people are generally supportive of tiger conservation, there is a huge residual demand for tiger products that could resurge if the ban on trade in tiger parts is lifted in China. We suspect that the current supply of the market is predominantly met by fakes or substitutes branded as tiger medicines, but not listing tiger as an ingredient. We suggest that the Traditional Chinese Medicine community should consider re-branding these products as bone-healing medicines in order to reduce the residual demand for real tiger parts over the long-term. The lifting of the current ban on trade in farmed tiger parts may cause a surge in demand for wild tiger parts that consumers say are better. Because of the low input costs associated with poaching, wild-sourced parts would consistently undercut the prices of farmed tigers that could easily be laundered on a legal market. We therefore recommend that the Chinese authorities maintain the ban on trade in tiger parts, and work to improve the enforcement of the existing ban.

Project description:Analysis of genetic variation can provide insights into ecological and evolutionary diversification which, for commercially harvested species, can also be relevant to the implementation of spatial management strategies and sustainability. In comparison with other marine biodiversity hot spots, there has been less genetic research on the fauna of the southwest Indian Ocean (SWIO). This is epitomized by the lack of information for lethrinid fish, which support socioeconomically important fisheries in the region. This study combines comparative phylogeographic and population genetic analyses with ecological niche modeling to investigate historical and contemporary population dynamics of two species of emperor fish (Lethrinus mahsena and Lethrinus harak) across the SWIO. Both species shared similarly shallow phylogeographic patterns and modeled historical (LGM) habitat occupancies. For both species, allele frequency and kinship analyses of microsatellite variation revealed highly significant structure with no clear geographical pattern and nonrandom genetic relatedness among individuals within samples. The genetic patterns for both species indicate recurrent processes within the region that prevent genetic mixing, at least on timescales of interest to fishery managers, and the potential roles of recruitment variability and population isolation are discussed in light of biological and environmental information. This consistency in both historical and recurrent population processes indicates that the use of model species may be valuable in management initiatives with finite resources to predict population structure, at least in cases wherein biogeographic and ecological differences between taxa are minimized. Paradoxically, mtDNA sequencing and microsatellite analysis of samples from the Seychelles revealed a potential cryptic species occurring in sympatry with, and seemingly morphologically identical to, L. mahsena. BLAST results point to the likely misidentification of species and incongruence between voucher specimens, DNA barcodes, and taxonomy within the group, which highlights the utility and necessity of genetic approaches to characterize baseline biodiversity in the region before such model-based methods are employed.

Dataset Information

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

Publications

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

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets