scholarly journals Genetic analyses reveal population structure and recent decline in leopards (Panthera pardus fusca) across Indian subcontinent

2019 ◽  
Author(s):  
Supriya Bhatt ◽  
Suvankar Biswas ◽  
Krithi K. Karanth ◽  
Bivash Pandav ◽  
Samrat Mondol
Keyword(s):  
Population Structure ◽  
Indian Subcontinent ◽  
Regional Scale ◽  
Population Decline ◽  
Ecological Monitoring ◽  
Panthera Pardus ◽  
Anthropogenic Pressures ◽  
Occupancy Modelling ◽  
Genetic Analyses ◽  
Large Carnivore

AbstractLarge carnivores maintain the stability and functioning of ecosystems. Currently, many carnivore species face declining population sizes due to natural and anthropogenic pressures. The leopard, Panthera pardus, is probably the most widely distributed and adaptable large carnivore, still persisting in most of its’ historic range. However, we lack subspecies level data on country or regional scale on population trends, as ecological monitoring approaches are difficult to apply on such wide-ranging species. We used genetic data from leopards sampled across the Indian subcontinent to investigate population structure and patterns of demographic decline. Our genetic analyses revealed four distinct subpopulations corresponding to Western Ghats, Deccan Plateau-Semi Arid, Shivalik and Terai region of north Indian landscapes, each with high genetic variation. Coalescent simulations with 13 microsatellite loci revealed a 75-90% population decline in between 120-200 years ago across India, possibly human induced. Population-specific estimates of genetic decline are in concordance with ecological estimates of local extinction probabilities in four sub-populations obtained from occupancy modelling of historic and current distribution of leopards in India. Our results confirm population decline of a widely distributed, adaptable large carnivore. We re-iterate the relevance of indirect genetic methods for such species, and recommend that detailed, landscape-level ecological studies on leopard populations are critical to future conservation efforts. Our approaches and inference are relevant to other widely distributed, seemingly unaffected carnivores such as the leopard.

scholarly journals Genetic analyses reveal population structure and recent decline in leopards (Panthera pardus fusca) across the Indian subcontinent

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8482
Author(s):  
Supriya Bhatt ◽  
Suvankar Biswas ◽  
Krithi Karanth ◽  
Bivash Pandav ◽  
Samrat Mondol
Keyword(s):  
Population Structure ◽  
Indian Subcontinent ◽  
Demographic History ◽  
Regional Scale ◽  
Population Decline ◽  
Local Extinction ◽  
Panthera Pardus ◽  
Anthropogenic Pressures ◽  
Genetic Analyses ◽  
Extinction Probabilities

Background Large carnivores maintain the stability and functioning of ecosystems. Currently, many carnivore species face declining population sizes due to natural and anthropogenic pressures. The leopard, Panthera pardus, is probably the most widely distributed and highly adaptable large felid globally, still persisting in most of its historic range. However, we lack subspecies-level data on country or regional scale on population trends, as ecological monitoring approaches are difficult to apply on such wide-ranging species. We used genetic data from leopards sampled across the Indian subcontinent to investigate population structure and patterns of demographic decline. Methods We collected faecal samples from the Terai-Arc landscape of northern India and identified 56 unique individuals using a panel of 13 microsatellite markers. We merged this data with already available 143 leopard individuals and assessed genetic structure at country scale. Subsequently, we investigated the demographic history of each identified subpopulations and compared genetic decline analyses with countrywide local extinction probabilities. Results Our genetic analyses revealed four distinct subpopulations corresponding to Western Ghats, Deccan Plateau-Semi Arid, Shivalik and Terai region of the north Indian landscape, each with high genetic variation. Coalescent simulations with microsatellite loci revealed a possibly human-induced 75–90% population decline between ∼120–200 years ago across India. Population-specific estimates of genetic decline are in concordance with ecological estimates of local extinction probabilities in these subpopulations obtained from occupancy modeling of the historic and current distribution of leopards in India. Conclusions Our results confirm the population decline of a widely distributed, adaptable large carnivore. We re-iterate the relevance of indirect genetic methods for such species in conjunction with occupancy assessment and recommend that detailed, landscape-level ecological studies on leopard populations are critical to future conservation efforts. Our approaches and inference are relevant to other widely distributed, seemingly unaffected carnivores such as the leopard.

scholarly journals Microsatellite analysis reveals low genetic diversity in managed populations of the critically endangered gharial (Gavialis gangeticus) in India

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Surya Prasad Sharma ◽  
Mirza Ghazanfarullah Ghazi ◽  
Suyash Katdare ◽  
Niladri Dasgupta ◽  
Samrat Mondol ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Indian Subcontinent ◽  
Population Decline ◽  
Mitochondrial Control Region ◽  
Critically Endangered ◽  
Term Survival ◽  
Low Level ◽  
Genetic Status ◽  
In The Wild ◽  
Gavialis Gangeticus

AbstractThe gharial (Gavialis gangeticus) is a critically endangered crocodylian, endemic to the Indian subcontinent. The species has experienced severe population decline during the twentieth century owing to habitat loss, poaching, and mortalities in passive fishing. Its extant populations have largely recovered through translocation programmes initiated in 1975. Understanding the genetic status of these populations is crucial for evaluating the effectiveness of the ongoing conservation efforts. This study assessed the genetic diversity, population structure, and evidence of genetic bottlenecks of the two managed populations inhabiting the Chambal and Girwa Rivers, which hold nearly 80% of the global gharial populations. We used seven polymorphic nuclear microsatellite loci and a 520 bp partial fragment of the mitochondrial control region (CR). The overall mean allelic richness (Ar) was 2.80 ± 0.40, and the observed (Ho) and expected (He) heterozygosities were 0.40 ± 0.05 and 0.39 ± 0.05, respectively. We observed low levels of genetic differentiation between populations (FST = 0.039, P < 0.05; G’ST = 0.058, P < 0.05 Jost’s D = 0.016, P < 0.05). The bottleneck analysis using the M ratio (Chambal = 0.31 ± 0.06; Girwa = 0.41 ± 0.12) suggested the presence of a genetic bottleneck in both populations. The mitochondrial CR also showed a low level of variation, with two haplotypes observed in the Girwa population. This study highlights the low level of genetic diversity in the two largest managed gharial populations in the wild. Hence, it is recommended to assess the genetic status of extant wild and captive gharial populations for planning future translocation programmes to ensure long-term survival in the wild.

scholarly journals Population structure and spatial distribution of porbeagles (Lamna nasus) in Irish waters

2019 ◽  
Vol 76 (6) ◽  
pp. 1581-1590 ◽  
Author(s):  
Luke W J Cameron ◽  
William K Roche ◽  
Jonathan D R Houghton ◽  
Paul J Mensink
Keyword(s):  
Population Structure ◽  
Spatial Distribution ◽  
North Atlantic ◽  
Population Decline ◽  
The North ◽  
Aggregation Site ◽  
Show Evidence ◽  
Long Term Trends ◽  
Almost All

Abstract Porbeagles throughout the North Atlantic have experienced severe population decline through overfishing, with the northeastern population listed as critically endangered. Management of this population is constrained by the paucity of data on porbeagle population structure, distribution and behaviour in this region. Here we use a long-term (47 year) Irish capture-mark-recapture dataset to investigate the population structure, spatial distribution and seasonal movements of this species. From 1970–2017, a total of 268 sharks (9 recaptures) were ID tagged, with most individuals likely being juvenile based on length at maturity estimates (mean total length = 143.9 cm, SD = 35.4). Almost all captures were recorded at three distinct locations near angling hubs along the south, west and north coasts with catches peaking in August. Long-term trends in capture date indicated a shift towards earlier capture dates in the northern site (n = 153). Our findings suggest Irish waters may act as a persistent summer aggregation site for juveniles, which show evidence for seasonal site fidelity, returning to nearby locations between years. These findings demonstrate the utility of such programmes, which can be implemented, with minimal expense by engaging with the angling sector, to elucidate the population structure and distribution of wide-ranging fish species.

scholarly journals A globally threatened shark, Carcharias taurus, shows no population decline in South Africa

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Juliana D. Klein ◽  
Aletta E. Bester-van der Merwe ◽  
Matthew L. Dicken ◽  
Arsalan Emami-Khoyi ◽  
Kolobe L. Mmonwa ◽  
...  
Keyword(s):  
South Africa ◽  
Census Data ◽  
Demographic History ◽  
Conservation Status ◽  
Population Decline ◽  
Multilocus Genotype ◽  
Population Declines ◽  
Effective Population ◽  
Anthropogenic Pressures ◽  
Carcharias Taurus

Abstract Knowledge about the demographic histories of natural populations helps to evaluate their conservation status, and potential impacts of natural and anthropogenic pressures. In particular, estimates of effective population size obtained through molecular data can provide useful information to guide management decisions for vulnerable populations. The spotted ragged-tooth shark, Carcharias taurus (also known as the sandtiger or grey nurse shark), is widely distributed in warm-temperate and subtropical waters, but has suffered severe population declines across much of its range as a result of overexploitation. Here, we used multilocus genotype data to investigate the demographic history of the South African C. taurus population. Using approximate Bayesian computation and likelihood-based importance sampling, we found that the population underwent a historical range expansion that may have been linked to climatic changes during the late Pleistocene. There was no evidence for a recent anthropogenic decline. Together with census data suggesting a stable population, these results support the idea that fishing pressure and other threats have so far not been detrimental to the local C. taurus population. The results reported here indicate that South Africa could possibly harbour the last remaining, relatively pristine population of this widespread but vulnerable top predator.

Genetic population structure of the fairy shrimp Branchinecta coloradensis (Anostraca) in the Rocky Mountains of Colorado

1998 ◽  
Vol 76 (11) ◽  
pp. 2049-2057 ◽  
Author(s):  
Andrew J Bohonak
Keyword(s):  
Population Structure ◽  
Gene Flow ◽  
Rocky Mountains ◽  
Regional Scale ◽  
Local Scale ◽  
Genetic Population Structure ◽  
Fairy Shrimp ◽  
Genetic Population ◽  
Contemporary Gene Flow ◽  
Branchinecta Coloradensis

Dispersal rates for freshwater invertebrates are often inferred from population genetic data. Although genetic approaches can indicate the amount of isolation in natural populations, departures from an equilibrium between drift and gene flow often lead to biased gene flow estimates. I investigated the genetic population structure of the pond-dwelling fairy shrimp Branchinecta coloradensis in the Rocky Mountains of Colorado, U.S.A., using allozymes. Glaciation in this area and the availability of direct dispersal estimates from previous work permit inferences regarding the relative impacts of history and contemporary gene flow on population structure. Hierarchical F statistics were used to quantify differentiation within and between valleys (thetaSV and thetaVT, respectively). Between valleys separated by 5-10 km, a high degree of differentiation (thetaVT = 0.77) corresponds to biologically reasonable gene flow estimates of 0.07 individuals per generation, although it is possible that this value represents founder effects and nonequilibrium conditions. On a local scale (<=110 m), populations are genetically similar (thetaSV = 0.13) and gene flow is estimated to be 1.7 individuals exchanged between ponds each generation. This is very close to an ecological estimate of dispersal for B. coloradensis via salamanders. Gene flow estimates from previous studies on other Anostraca are also similar on comparable geographic scales. Thus, population structure in B. coloradensis appears to be at or near equilibrium on a local scale, and possibly on a regional scale as well.

scholarly journals Tracing the biogeographical origin of South Asian populations using DNA SatNav

2016 ◽  
Author(s):  
Ranajit Das ◽  
Priyanka Upadhyai
Keyword(s):  
Population Structure ◽  
South Asian ◽  
South India ◽  
Indian Subcontinent ◽  
Population History ◽  
Genetic Admixture ◽  
Indian Populations ◽  
Asian Populations ◽  
South Indian ◽  
North And South

AbstractThe Indian subcontinent includes India, Bangladesh, Pakistan, Nepal, Bhutan, and Sri Lanka that collectively share common anthropological and cultural roots. Given the enigmatic population structure, complex history and genetic heterogeneity of populations from this region, their biogeographical origin and history remain a fascinating question. In this study we carried out an in-depth genetic comparison of the five South Asian populations available in the 1000 Genomes Project, namely Gujarati Indians from Houston, Texas (GIH), Punjabis from Lahore (PJL), Indian Telugus from UK (ITU), Sri Lankan Tamils from UK (STU) and Bengalis from Bangladesh (BEB), tracing their putative biogeographical origin using a DNA SatNav algorithm - Geographical Population Structure (GPS). GPS positioned >70% of GIH and PJL genomes in North India and >80% of ITU and STU samples in South India. All South Asian genomes appeared to be assigned with reasonable accuracy, along trade routes that thrived in the ancient Mauryan Empire, which had played a significant role in unifying the Indian subcontinent and in the process brought the ancient North and South Indian populations in close proximity, promoting admixture between them, ~2300 years before present (YBP). Our findings suggest that the genetic admixture between ancient North and South Indian populations likely first occurred along the Godavari and Krishna river basin in Central-South India. Finally our biogeographical analyses provide critical insights into the population history and sociocultural forces driving migration patterns that may have been instrumental in shaping the population structure of the Indian subcontinent.

Sign in / Sign up

Export Citation Format

Share Document