Effects of a reintroduced tiger population on large carnivores in Panna Tiger Reserve, central India

We applied maximum likelihood (ML-SECR) and Bayesian (B-SECR) spatially explicit capture-recapture methods to estimate density, abundance and the spatial scale of detection (σ). Tiger density increased from 3.77±0.79 to 6.69±1.06 per 100 km² (ML-SECR) and 2.1±0.14 to 4.23±0.31 per 100 km² (B-SECR), with a female-biased population structure. Leopard density, the highest reported across Indian tiger reserves, ranged from 23.87±2.21 and 30.07±2.31 per 100 km² (ML-SECR) and 19.70±1.39 to 22.87±1.34 per 100 km² (B-SECR), exhibiting a marginal declining trend.

Hyena density remained stable (13.76±1.49 to 16.58±1.64 per 100 km² ML-SECR; 8.22±0.35 to 9.25±0.55 per 100 km², B-SECR), reflecting adaptive responses to resource competition. The spatial scale parameter (σ) was highest in tigers, followed by hyenas and leopards, with males exhibiting larger ranges than females. Spatial analysis revealed that leopard density was higher in areas of low tiger density, with pronounced seasonal segregation during summer.

The recovering tiger population did not suppress leopard density; instead, intense intra-specific competition emerged as the primary driver of leopard population dynamics. Declining σ with increasing carnivore density indicates density-dependent home-range compression across all three species.