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 Ivlevs index- 0.85) and showed the 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 the 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, dominated 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.

Summary Grassland habitats currently face severe anthropogenic exploitation, thereby affecting the survival of grassland-dependent biodiversity globally. The biodiversity-rich grasslands of India lack quantitative spatiotemporal information on their status. We evaluated the status of upper Gangetic Plains grasslands in 2015 and compared it with those from 1985, 1995 and 2005. On-ground mapping and visual classifications revealed a 57% decline in these grasslands between 1985 (418 km2) and 2015 (178 km2), mostly driven by habitat conversion (74% contribution by cropland). Limited radiotelemetry data from endemic swamp deer indicated a possible grassland-dominated average home range size of 1.02 km2, and these patches were highly preferred (average Ivlev’s index = 0.85) over other land-use classes at both spatial and temporal scales. Camera-trapping within the core habitats suggests the critical use of these patches as fawning/breeding grounds. Habitat suitability analysis indicates only c. 17% of the area along the Ganges is suitable as swamp deer habitat. We recommend the protection of these critical grassland patches to maintain ‘dynamic corridors’, with restoration and other management approaches involving multiple stakeholders to ensure the survival of this critical ecosystem.

The Indian subcontinent has witnessed disproportionate declines in large mammalian herbivore communities. The northern swamp deer (Rucervus duvaucelii duvaucelii) exemplifies the conservation challenges of typical non-protected area species, where apart from distribution status other ecological information is limited for the upper Gangetic basin population. We combined elements of radio-telemetry and conservation genetics to evaluate dispersal patterns, population connectivity and assess genetic variation and inbreeding status of this population living across a highly human-dominated area. We genetically identified 266 unique swamp deer and further analyses revealed presence of two spatially-admixed genetic lineages with moderate heterozygosity (Ho=0.51, SD= 0.10) and low inbreeding (FIS=0.133) status. Multi-disciplinary evidence suggests that the small, isolated grassland patches between Jhilmil Jheel Conservation Reserve (JJCR) and Hastinapur Wildlife Sanctuary (HWLS) are highly preferred by swamp deer during migrations and are genetically connected. The southern part of the area in HWLS showed early signatures of genetic discontinuity that require immediate conservation attention. We hypothesized that the human settlement history of this landscape, river dynamics and species ability to negotiate various pressures and disperse has helped to maintain such connectivity. While these signatures are encouraging for this small, isolated cervid population, careful management interventions are required to ensure the integrity and functionality of this landscape. We recommend a scientifically robust population estimation approach across this landscape and a multi-stakeholder-driven strategies to augment population and habitat recovery, plantation and riverscape management to ensure long-term survival of this species.