Habitat Suitability Modeling for the Hill-Stream Loach Triplophysa kashmirensis (Hora, 1925): Identifying Optimal Environmental Conditions and Conservation Priorities in the Kashmir Himalaya

Habitat suitability modeling plays a vital role in identifying the environmental conditions required by species and provides a scientific basis for developing effective conservation strategies, particularly for threatened taxa. This study developed a comprehensive Habitat Suitability Index (HSI) model for Triplophysa kashmirensis, a critically endangered, non-migratory hill-stream loach endemic to the Kashmir Valley, using telemetry data from 279 detection events across 9 sites in Tulmullah Stream during the pre-monsoon season of 2026. 
The geometric mean HSI across all detections was 0.842 (range: 0.660–1.000), with 88.2% of locations classified as high-quality or optimal habitat. Optimal environmental ranges were identified as water temperature 15.69–16.90°C, dissolved oxygen 7.98–10.83 mg/L, pH 7.60–7.77, flow velocity 0.28–0.51 m/s, and depth 0.80–1.05 m. Principal component analysis demonstrated that 66.2% of environmental variation was explained by a single gradient positively correlated with all parameters. Habitat occupancy was strongly associated with riffle habitats (48.7% of detections) and pool habitats (40.5%), with preferences for cobble (33.0%) and gravel-silt (26.5%) substrates.  As a non-migratory species with strong site fidelity, T. kashmirensis depends entirely on the ecological integrity of its resident stream reaches rather than on connectivity to distant refugia, meaning individuals cannot relocate to escape localized habitat degradation; this restricted-range ecology heightens the urgency of targeted, site-specific conservation in Kashmir over landscape-scale connectivity measures.