Amolops formosus, Assam Cascade Frogs, can act as key indicators of stream health because they are a rare endemic species of the Himalayas associated with riparian habitats. For a robust density estimate, we employed the first spatially explicit capture-recapture study of an anuran species in the Western Himalayas using individual identification without physical capture. We identified 51 individuals from two sampled streams. Minimum average movement was 57.14 ± 7.14 m and 75 ± 11.18 m in the two streams, respectively. Average abundance of A. formosus was 12.73 ± 2.83 individuals based on the top N-mixture model. Water flow showed a statistically significant negative correlation with frog abundance. Density was evaluated using spatially explicit capture-recapture methods. Mean density was 5.58 ± 1.95 and 5.11 ± 1.61 individuals/ha in the two streams, respectively. Meanwhile, mean density based on linear habitat was 90.51 ± 21.68 and 87.53 ± 18.81 individuals/km. Our study demonstrated the use of spatially explicit techniques for quantifying and monitoring important sentinel species such as A. formosus using different stream parameters.