Hyderabad: A four-decade study in the Anamalai hills of the Western Ghats has delivered a sobering message about the endangered lion-tailed macaque: Population growth outside protected areas may look encouraging, but it could mask deeper fragility rather than recovery. Researchers tracked lion-tailed macaque groups across fragmented forests for 40 years, documenting 37 groups with a combined strength of about 800 individuals. The long-term assessment found that mean group sizes were larger in non-protected areas than inside protected forests. But the apparent surge comes with caveats. The study warns that higher growth in some non-protected fragments may be shaped by proximity to human settlements and access to anthropogenic food, along with reduced canopy continuity and rising negative human-primate interactions. In other words, the numbers may be rising for reasons that increase long-term risk. Titled ‘Differential demographic responses of lion-tailed macaques to habitat fragmentation: Four decades of population monitoring in the Anamalai Hills, Western Ghats and perspectives of management and conservation’, the research is part of a collaborative effort involving Professor Mewa Singh of the University of Mysore and G Umapathy of LaCONES (Laboratory for the Conservation of Endangered Species). The findings also reflect continuity across three generations of researchers engaged in the work. Growth at a cost According to the study, groups in non-protected fragments are likely to face greater long-term vulnerability due to anthropogenic disturbance. It flags threats such as road mortality and electrocution, alongside the twin pressures of habitat fragmentation and growing dependence on human-linked food sources.Within these non-protected landscapes, high growth in specific fragment, particularly the Puthuthottam population, appeared to stem from local ecological context rather than any broader landscape-level recovery. Researchers caution that such spikes should not be mistaken for signs of long-term viability, especially when short-term demographic ‘success’ is tied to human-associated food and interactions that heighten conflict and risk. Healthier patterns In contrast, groups within protected areas remained largely stable over time. Birth rates did not vary significantly across fragments, but the analysis found a negative correlation between group size and canopy height. Protected fragments also supported a higher proportion of adult females to immatures, and adults to immatures, than non-protected fragments — a demographic structure the study describes as healthier than that seen outside protected settings. The broader takeaway is clear: Rising numbers alone do not tell the full story. For the lion-tailed macaque, true recovery may depend less on visible growth and more on the quality and security of the habitat that sustains it.
