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Suryawanshi, K.

Publications and source records attributed to Suryawanshi, K..

10 recordsLinked to original sources

Snow leopard-mediated apparent competition between wild ungulates and domestic livestock in the Trans-Himalaya

Across High Asia, snow leopards Panthera uncia share habitats with pastoralists and consume both wild and domestic herbivores. Increasing wild prey is vital for predator conservation, but its effect on livestock depredation is unclear: it could decrease depredation through apparent facilitation or increase it through apparent competition. We investigated this association using a 13-year time series dataset from Upper Spiti Landscape in the Indian Trans-Himalaya. Long-term data on elusive carnivores are rare, making this time series especially valuable for testing predator-mediated interactions. We found higher wild ungulate density was accompanied by significantly greater depredation of free-ranging livestock, and this association remained positive after bootstrapping to account for uncertainty in density estimates. These results suggest snow leopard-mediated apparent competition between wild and domestic herbivores. We recommend conservation efforts that increase wild prey must also integrate effective livestock protection and support strategies to enhance coexistence between predators, prey and pastoralists.

ecology↗

Forest Owlet or Farmer's owlet: Scale-dependent habitat selection reveals conditional compatibility between Forest Owlet conservation and traditional agroforestry in Gujarat, India

Understanding how species that are threatened with extinction utilise human-modified landscapes is essential for evidence-based conservation. We investigated multi-scale habitat selection by the Forest Owlet (Athene blewitti), an Endangered species, endemic to central India with fewer than 1000 mature individuals, in the Dangs district of Gujarat, the westernmost extent of its range. Using a hierarchical Bayesian occupancy framework, we examined how forest cover and three agricultural land-use types (dry agriculture with trees, dry agriculture without trees, and intensive agriculture) affected occupancy across three nested spatial scales: regional (81 km2), landscape (4 km2), and territory (0.25 km2). At the regional scale, the forest x agriculture interaction term was significantly negative ({beta} = -6.82, 95% CI: -9.87 to -1.59), indicating that owlets favour agroforestry-dominated regions over forest-dominated landscapes. Conversely, at the landscape scale, a significant positive interaction ({beta} = 1.36, 95% CI: 0.41-2.50) revealed synergistic benefits from forest-agriculture mosaics. Agriculture type strongly influenced landscape-scale occupancy: dry agriculture with trees showed positive effects ({beta} = 1.17, 95% CI: 0.43-2.02), whereas dry agriculture without trees had significant negative effects ({beta} = -1.19, 95% CI: -2.28 to -0.29). These findings demonstrate that Forest Owlets are not forest-obligate specialists but occupy complex agroforestry mosaics, requiring multi-scale conservation strategies. We propose that the traditional Malki agroforestry system, which incentives tree retention on farmland, offers conditional compatibility with Forest Owlet conservation, provided that mature cavity-bearing trees and small forest patches are explicitly protected.

ecology↗

What's next for Indian Ornithology? 101 key research questions

India has a rich history of ornithology, and bird research in this field has expanded considerably in recent decades, spurred by a growing number of birdwatchers and ornithologists. Despite this progress, critical gaps remain. This paper highlights key areas where further research is needed and identifies pressing questions that will shape Indian ornithology in the coming years. Drawing from diverse inputs, we present a curated list of 101 research questions spanning across the various disciplines in ornithology - Natural History, Physiology and Disease Ecology, Behaviour, Population and Community Ecology, Habitat Ecology, Macroecology and Biogeography, Population Genetics and Evolution, Applied/Economic Ornithology and Conservation. The list was compiled through a multi-stage process, starting with a public open call for questions, followed by review and curation by a smaller panel of subject specialists. Each question was independently scored by a panel of experts based on three criteria: generality, novelty, and relevance. To account for variation in scoring styles, scores were normalised using Z-scores. The top 101 research questions were then selected based on these standardised scores. Each question is accompanied by an annotation that describes the significance of the question, and highlights opportunities to address it. While our list of research questions highlights significant research priorities, it is not intended to be exhaustive. Rather, it reflects the perspectives of those involved in its curation, who deemed these questions particularly relevant and impactful towards advancing Indian ornithology. We expect these questions to spark new project ideas among students, researchers, and citizen scientists, while guiding funders, managers, and policymakers toward priority research areas.

ecology↗

Biocultural vulnerability of traditional crops in the Indian Trans Himalaya

Traditional agricultural landscapes are critical for conserving biocultural and ecological diversity. Despite their significance, traditional systems have often been overlooked, leading to genetic erosion of crop landraces. Using the fragile ecosystems of northwest Himalaya as case study, we examine the ecological and genetic resilience of an understudied and lesser-known traditional crop, black pea, and barley (Hordeum vulgare) and compare them to the introduced cash crop of green pea (Pisum sativum L.). We co-designed field experiments with local farmers to assess survival and reproductive traits for the crops. We performed whole-genome sequencing to investigate the genetic diversity of black pea and describe their nutritional profile. Our findings indicate that traditional crops are better adapted to local climatic conditions and hold considerable genetic diversity and nutritional potential. We emphasize the importance of integrating traditional knowledge with scientific research to promote sustainable food systems and socio-ecological stability in vulnerable mountain regions.

plant biology↗

State of India's Birds 2023: A framework to leverage semi-structured citizen science for bird conservation

Birds and their habitats are threatened with extinction around the world. Regional assessments of the State of Birds are a vital means to prioritize data-driven conservation action by informing national and global policy. Such evaluations have traditionally relied on data derived from extensive, long-term, systematic surveys that require significant resources, limiting their feasibility to a few regions in the world. In the absence of such structured long-term datasets, semi-structured datasets have recently emerged as a promising alternative in other regions around the world. Semi-structured data are generated and uploaded by birdwatchers to citizen science platforms like eBird. Such data contain inherent biases because birdwatchers are not required to adhere to a fixed protocol. An evaluation of the status of birds from semi-structured data is therefore a difficult task that requires careful curation of data and the use of robust statistical methods to reduce errors and biases. In this paper, we present a methodology that was developed for this purpose, and was applied to produce the comprehensive State of Indias Birds (SoIB) 2023 report. SoIB 2023 assessed the status of 942 bird species in India by evaluating each species based on three metrics: 1) long-term change: change in abundance between the year 2022 and the year-interval pre-2000; 2) current annual trend: mean annual change in abundance from 2015 to 2022; and 3) distribution range size. We found evidence that 204 species have declined in the long term, and 142 species are currently declining. We present and discuss important insights about Indias birds that can guide research and conservation action in the region. We hope that the detailed methodology described here can act as a blueprint to produce State of Birds assessments from semi-structured citizen science datasets and springboard conservation action in many other regions where structured data is lacking but strong communities of birders exist. Open Research StatementThe primary data are already publicly available on eBird (Sullivan et al. 2014), and other data are already published in a GitHub repository (stateofindiasbirds 2024).

ecology↗

Is the population of the Critically Endangered White-bellied Heron in Namdapha Tiger Reserve, India, declining?

The Critically Endangered White-bellied Heron Ardea insignis is a large-bodied, range-restricted, piscivorous bird found in the Himalayan mountains. With fewer than 60 individuals remaining globally, regular monitoring efforts are required to understand the conservation status of this rare species better. Here, we present the results of river surveys from 2017 and 2023-24 for the White-bellied Heron in an important protected area, the Namdapha Tiger Reserve, in Arunachal Pradesh. The encounter rate in 2017 was 0.55 herons per km, however; we did not detect the bird during intensive river sampling in the same stretches in 2023-24. This area within the reserve was once a stronghold for the species and they currently appear to be declining or locally extinct. Given the declines within this Protected Area, the drivers for the same need to be determined. While repeated monitoring of rivers has helped reveal this decline, locating and conserving stretches of river utilised by the remaining individuals away from the core zone is now critical. [Supplementary material for this article can be found at https://doi.org/xxx]

ecology↗

Chronic disturbance of moist tropical forests favours deciduous over evergreen tree communities across a climate gradient in the Western Ghats

It is well established that climatic factors such as water stress and chronic anthropogenic disturbances such as biomass extraction influence tropical forest tree community structure, richness and composition. However, while the standalone effects of these two drivers on plant communities are well-studied, their interactive effects are not. Moist tropical forests in Indias Western Ghats face a dual threat from increasingly erratic precipitation (and consequent water stress), and an intensifying anthropogenic footprint. Here, we sampled 120 tree plots (0.05 ha each) across forests with varying histories of biomass extraction and a gradient in climate water deficit (CWD, a proxy for water stress) within a 15,000 km2 landscape in the northern Western Ghats and examined whether and how disturbance history modulates relationships of tree community structure and composition with climate. As expected, tree species richness increased with decreasing water stress in less- and historically-disturbed forests but remained low in repeatedly-disturbed forests. The increase in evergreen species richness with decreasing water stress was far slower in repeatedly-disturbed forests than other categories, and the relative abundance of evergreens in the repeatedly-disturbed forests (25%) was half that in less-disturbed forests (50%) of comparable water stress in the driest parts. Overall, we show that disturbance can amplify threats from climate change to wet forest-associated evergreen tree species, many of which are threatened, while benefiting more widely distributed dry forest-associated deciduous species. In the northern Western Ghats, where much of the remaining forest cover is disturbed and dominated by deciduous tree species, the persistence of evergreen tree flora hinges on protecting existing evergreen forest patches from future disturbances and restoring locally appropriate evergreen species in secondary forests.

ecology↗

Conservation value of low-elevation forests for birds in agroforestry-dominated landscapes in a biodiversity hotspot

O_LIProtected areas (PAs) and multi-use landscapes beyond PAs play important and complementary roles in conserving global biodiversity. Across the tropical forest biome, remnant forests and agroforestry plantations in mixed-use landscapes often have high taxonomic diversity, but their ability to sustain functionally and phylogenetically diverse assemblages and retain conservation-priority species is unclear. Additionally, our understanding of impacts of land-use change across species, function and communities is poor. C_LIO_LIIn Indias Western Ghats (WG) biodiversity hotspot, like in many other tropical regions, PAs cover just 12% of the land and are concentrated in higher elevations. Here, in an approximately 15,000 km2 landscape in the northern WG, we compared bird communities across six land-use categories: state-owned high-elevation PAs and low-elevation Reserved Forests beyond PAs, and privately-owned periodically clear-felled low-elevation forests and three types of low-elevation agroforestry plantations (cashew, mango, and rubber). C_LIO_LIWe sampled 184 line transects totalling 137.5 km across habitats, compared taxonomic, functional, and phylogenetic diversity metrics and used joint species distribution models to test for species-trait-habitat associations. C_LIO_LIForests in general and lowland forests in particular had higher taxonomic, functional and phylogenetic diversity, and higher occurrence probabilities of evergreen forest-affiliated, conservation-priority, and frugivores than agroforestry plantations. The ranking of land-use types varied across indicators, with rubber ranking higher than cashew and mango for functional and phylogenetic diversity but lower in species occurrence probabilities. C_LIO_LISynthesis and Applications: Our findings underscore the irreplaceability of less-disturbed forests for birds in mixed-use landscapes, especially when considering multiple dimensions of biodiversity, habitat specialists, and conservation-priority species. We advocate the simultaneous examination at multiple levels (community, species and traits) to determine the impacts of land-use change as divergent information of conservation importance is gleaned from each level. Reserved and private forests of low elevations of the Northern Western Ghats are critical for avian conservation, given that they harbour significant diversity, and the absence of representative PAs in the region. Given the vulnerability of these low-elevation forests to conversion for non-forestry activities and overexploitation for fuelwood, there is a need to develop viable models of partnership with landowners in these multi-use landscapes for ecological restoration of degraded forests. C_LI

ecology↗

Key informant perceptions on wildlife hunting in India during the COVID-19 lockdown

Lockdowns intended to control the COVID-19 pandemic resulted in major socioeconomic upheavals across the world. While there were numerous reports of these lockdowns benefiting wildlife by reducing human movement and habitat disturbance, increased hunting during these lockdowns emerged as a conservation concern, particular in tropical Asia and Africa. We used online interviews with key informants including wildlife researchers, enforcement staff and NGO employees (N=99), and media reports (N=98), to examine the impacts of Indias COVID-19 lockdown (March-May 2020) on wildlife hunting across the country. We asked whether and how hunting patterns changed during the lockdown, and explored socioeconomic and institutional factors underlying these changes. Over half the interviewees spread over 43 administrative districts perceived hunting (mammals, in particular) to have increased during the lockdown relative to a pre-lockdown reference period. Interviewees identified household consumption (53% of respondents) and sport and recreation (34%) as main motivations for hunting during the lockdown, and logistical challenges for enforcement (36%), disruption of food supply (32%), and need for recreational opportunities (32%) as key factors associated with hunting during this period. These insights were corroborated by statements by experts extracted from media articles. Collectively, our findings suggest that the COVID-19 lockdown potentially increased hunting across much of India, and emphasize the role of livelihood and food security in mitigating threats to wildlife during such periods of acute socioeconomic perturbation.

ecology↗

Spatial variation in population-density of snow leopards in a multiple use landscape in Spiti Valley, Trans-Himalaya

The endangered snow leopard Panthera uncia occurs in human use landscapes in the mountains of South and Central Asia. Conservationists generally agree that snow leopards must be conserved through a land-sharing approach, rather than land-sparing in the form of strictly protected areas. Effective conservation through land-sharing requires a good understanding of how snow leopards respond to human use of the landscape. Snow leopard density is expected to show spatial variation within a landscape because of variation in the intensity of human use and the quality of habitat. However, snow leopards have been difficult to enumerate and monitor. Variation in the density of snow leopards remains undocumented, and the impact of human use on their populations is poorly understood. We examined spatial variation in snow leopard density in Spiti Valley, an important snow leopard landscape in India, via spatially explicit capture recapture analysis of camera trap data. We camera trapped an area encompassing a minimum convex polygon of 953 km2. We estimated an overall density of 0.49 (95% CI: 0.39-0.73) adult snow leopards per 100 km2. Using AIC, our best model showed the density of snow leopards to depend on wild prey density, movement about activity centres to depend on altitude, and the expected number of encounters at the activity centre to depend on topography. Models that also used livestock biomass as a density covariate ranked second, but the effect of livestock was weak. Our results highlight the importance of maintaining high density pockets of wild prey populations in multiple use landscapes to enhance snow leopard conservation.

ecology↗