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Biology subjects

Thatte, P.

Publications and source records attributed to Thatte, P..

3 recordsLinked to original sources

Prioritizing landscapes to reconcile biodiversity conservation, ecosystem services, and human well-being in India

Biodiversity conservation and human well-being are tightly interlinked; yet mismatches in the scale at which both priorities are planned and implemented have exacerbated biodiversity loss, erosion of ecosystem services, and declining human quality of life. India houses the second largest human population on the planet, while <5% of the countrys land area is effectively protected for conservation. This warrants landscape-level conservation planning through a judicious mix of land-sharing and land-sparing approaches, and co-production of ecosystem services. Through a multi-faceted assessment, we prioritize spatial extents of land parcels that, in the face of anthropogenic threats, can safeguard conservation landscapes across Indias biogeographic zones. We find that only a fraction (~15%) of such priority areas identified here are encompassed under Indias extant PA network, and several landscapes of high importance were omitted in all previous global-scale assessments. We then examined the spatial congruence of priority areas with administrative units earmarked for economic development by the Indian government, and propose management-zoning through state-driven and participatory approaches. Our spatially explicit insights can help meet the twin goals of biodiversity conservation and sustainable development in India and other countries across the Global South.

ecology↗

Human footprint differentially impacts genetic connectivity of four wide-ranging mammals in a fragmented landscape

AimMaintaining connectivity is critical for long-term persistence of wild carnivores in landscapes fragmented due to anthropogenic activity. We examined spatial genetic structure and the impact of landscape features on connectivity in four wide-spread species- jungle cat (Felis chaus), leopard (Panthera pardus), sloth bear (Melursus ursinus) and tiger (Panthera tigris). Location Our study was carried out in the central Indian landscape, a stronghold in terms of distribution and abundance of large mammals. The landscape comprises fragmented forests embedded in a heterogeneous matrix of multiple land-use types.\n\nMethodsMicrosatellite data from non-invasively sampled individuals (90 jungle cats, 82 leopards, 104 sloth bears and 117 tigers) were used to investigate genetic differentiation. Impact of landscape features on gene flow was inferred using a multi-model landscape resistance optimization approach.\n\nResultsAll four study species revealed significant isolation by distance (IBD). The correlation between genetic and geographic distance was significant only over a short distance for jungle cat, followed by longer distances for sloth bear, leopard and tiger. Overall, human footprint had a high negative impact on geneflow in tigers, followed by leopards, sloth bears and the least on jungle cats. Individual landscape variables- land-use, human population density, density of linear features and roads- impacted the study species differently. Although land-use was found to be an important variable explaining genetic connectivity for all four species, the amount of variation explained, the optimum spatial resolution and the resistance offered by different land-use classes varied.\n\nMain conclusionsAs expected from theory, but rarely demonstrated using empirical data, the pattern of spatial autocorrelation of genetic variation scaled with dispersal ability and density of the study species. Landscape genetic analyses revealed species-specific impact of landscape features and provided insights into interactions between species biology and landscape structure. Our results emphasize the need for incorporating functional connectivity data from multiple species for landscape-level conservation planning.

ecology↗

Protected corridors preserve tiger genetic diversity and minimize extinction into the next century

Habitat loss is the greatest threat to large carnivores around the world. Maintenance of functional connectivity in fragmented landscapes will be important for long-term species persistence. Here, we merge landscape genetics analyses and spatially-explicit simulations to understand future persistence and extinction of tigers (Panthera tigris) in Central India. Tigers in this landscape are restricted to Protected Areas (PAs) and forest fragments embedded within a mosaic of agricultural fields and human settlements. We examined current population connectivity of tigers across nine reserves (using 116 non-invasively sampled individuals and 12 microsatellites). Genetic data was used to infer resistance-to-movement. Our results suggest that dense human settlements and roads with high traffic are detrimental to tiger movement. We used landscape genetic simulations to model 86 different scenarios that incorporated impacts of future land-use change on inferred population connectivity and extinction. Our results confirm that genetic variability (heterozygosity) will decrease in the future and small and/or isolated PAs will have a high risk of local extinction. The average extinction risk of small PAs reduced by 23-70% on adding a 5 km buffer around exiting boundaries. Unplanned development results in 35% lower heterozygosity and 56% higher average extinction probability for tigers even within protected areas. Increasing tiger numbers in such a scenario decreases extinction probability just by 12 % (from 56% to 44%). Scenarios where habitat connectivity was enhanced and maintained, stepping-stone populations were introduced/maintained, and tiger numbers were increased, led to low overall extinction probability (between 3-21%). Our simulations provide a means to quantitatively evaluate the effects of different land-use change scenarios on connectivity and extinction, linking basic science to land-use change policy and planned infrastructure development.

genetics↗