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Grassland habitats currently face severe anthropogenic exploitations leading to cascading effects on the survival of grassland-dependent biodiversity globally, particularly in non-protected areas. Significant amount of such biodiversity-rich grasslands in India are found outside protected areas but lack quantitative information on their status. We evaluated the current and historical (30 years) status of the grasslands using a combination of intensive field surveys and GIS tools across one of the most fertile, human-dominated region: the upper Gangetic Plains of north India. On-ground mapping and visual classifications revealed 57% decline in grassland habitats between 1985 (418 km2) and 2015 (178km2), mostly driven by conversion to croplands (74% contribution). Radio-telemetry data from the largest endemic cervid swamp deer (n=2) showed grassland-dominated average home range (50% BBMM) size of 1.02 km2. The animals highly preferred these patches (average Ivlev’s index- 0.85) and showed highest temporal continuity (88%) compared to other LULC classes. Camera trapping within the core habitats suggests critical use of these patches as fawning/breeding grounds. Habitat suitability analysis indicates only ∼18% of the entire area along Ganges is suitable for swamp deer. Accurate mapping (86% accuracy) and characterization of four major grass species revealed a total 144.04 km² vegetation area, dominted by Saccharum sp. (35%). We recommend protection and recovery of these critical grassland patches to maintain ‘dynamic corridors’ and other appropriate management strategies involving multiple stakeholders to ensure survival of this critical ecosystem. Such evaluations, if spatially expanded, would be critical to restore this rapidly vanishing ecosystem worldwide.

The swamp deerRucervus duvauceliiis the largest grassland-dwelling endemic cervid of India and Nepal. With a declining population trend across its range, this species is found in fragmented habitats of northern, north-eastern and central India and south-western Nepal. The northern swamp deer subspeciesRucervus duvaucelii duvauceliioccurs in small wetland patches across the states of Uttarakhand and Uttar Pradesh in India and has lost most of its habitat in the last century. Information about the distribution of the swamp deer in the upper Gangetic plains is limited, except in the Jhilmil Jheel Conservation Reserve in Uttarakhand and around the Bijnor barrage area of Hastinapur Wildlife Sanctuary in Uttar Pradesh. We surveyed the upper Gangetic plains between the Reserve and the Sanctuary, including some adjoining areas and three tributaries of the Ganges, to assess the status of these habitats, current swamp deer distribution and the threats faced by the species. We found several areas harbouring swamp deer within non-protected wetlands along the entire surveyed stretch of the upper Ganges and a previously unreported population in Uttar Pradesh. We documented major threats including habitat conversion, livestock grazing, poaching, conflict and other anthropogenic disturbances. We recommend community driven conservation and management ofRucervus duvaucelii duvauceliiin this fragmented landscape to ensure survival of this species and other threatened fauna of these wetlands and grasslands.

Burgeoning pressures of habitat loss is a major cause of herbivore decline across India, forcing them to coexist with humans in non-protected areas. Their conservation in such landscapes is challenging due to paucity of ecological and demographic information. The northern subspecies of swamp deer, Rucervus duvaucelii duvaucelii, is one such herbivore that lives across human-dominated landscapes in Terai region and upper Gangetic plains of north India. Here, we describe species-specific molecular markers and a cervid-specific molecular sexing assay for swamp deer and four other coexisting cervids sambar, chital, barking deer and hog deer. Our markers show species-specific band patterns and a high success rate of 88.21% in large number of field collected reference samples for all species. Faecal pellets from pilot swamp deer survey samples from upper Ganges basin show 93.81% success rate, and only 5.5% misidentification based on morphological characteristics. Our cervid-specific molecular sexing multiplex assay accurately ascertained 81.15% samples to respective sexes. These molecular approaches provide an easy, quick and cheap option to generate critical information on herbivore population parameters and aid their conservation in this mosaic of protected and non-protected grassland habitats.

Recent declines in large herbivores have led to significant conservation efforts globally. However, the niche-specific megaherbivores residing outside protected areas face more imminent extinction threats. Swamp deer, the obligate grassland-dwelling endemic cervid is the most extinction-prone megaherbivore in the Indian subcontinent. Limited information on distribution and habitat status pose significant conservation and management challenges for the remaining fragmented populations in north, north-east and central India. To this end, we combined exhaustive field surveys and Maximum Entropy (MaxEnt) modeling to generate the most detailed distribution map for the northern swamp deer subspecies. We used primary data from more than 6000 km2 field surveys and eight ecologically relevant covariates for model predictions. Grassland cover, annual mean temperature and distance from water were the major factors that predicted the species distribution. Models predicted swamp deer distribution in only ~3% of the entire landscape, covering both protected (~1.4%) as well as non-protected (~1.6%) areas. Our validation surveys in some of these predicted areas confirmed swamp deer presence and indicated ~85% model accuracy. Finally, we identified four ‘Priority Conservation Areas’ still retaining adequate grassland habitat and species presence that require immediate attention to ensure population connectivity across this landscape. These results highlight the importance of the marginalized grassland ecosystems of northern India that still retains high biodiversity. We suggest a swamp deer-centric conservation approach to protect these human-dominated habitats and emphasize in generating such information for other endemic, habitat-specialist species across the globe.

The Okhla Bird Sanctuary (OBS), a man-modified floodplain wetland having high human impact, is located in an urbanized landscape. Its location in the Central Asian Flyway of migratory birds makes it an ideal transit and wintering ground for birds. This paper describes the vegetation composition and significance of the Sanctuary as a bird habitat. A floristic survey was carried out from winter 2009 to spring 2010 while preparing a management plan for OBS. 192 species of plants belonging to 46 families were recorded from the area. Thirteen species of weeds were observed covering 70% of the sampled area in peak summer. Among trees, highest density was found for two exotic species viz., Leucaena leucocephala and Prosopis juliflora. The aquatic system is facing threat from proliferation of Eichhornia cressipes and Typha angustifolia. Strategic eradication of invasive and plantation of native species in the sanctuary are needed for better management.

The primary explanation for the latitudinal gradient in species diversity must lie in why species fail to expand ranges across different climatic regimes. Theories of species gradients based in niche conservatism assume that whole clades are confined to particular climatic regimes because the traits they share limit adaptation to alternative regimes. We assess these theories in an analysis of the twofold decline in bird species richness along the Himalayas from the southeast to the northwest. The presence of fewer species in the northwest is entirely due to a steep decline in the number of forest species; species occupying more open habitats show a reversed gradient. Forest species numbers are exceptionally high at midelevations (1,000-2,000 m) in the southeast, which experience a warm, wet climate not present in the northwest, and a high proportion of these species fail to expand their range to the northwest. Despite this, many species do have populations or close relatives that straddle different climatic regimes along altitudinal gradients and/or the regional gradient, implying that climate-based niche conservatism per se does not strongly constrain range limits. We argue that climate- and competition-mediated resource distributions are important in setting northerly range limits and show that one measure of forest resources (foliage density) is lower in the northwest.