Species in News: Lion-Tailed Macaques

Species in News: Lion-Tailed Macaques
  • Context:

  • A recent study published in the Journal for Nature Conservation reveals that the endangered lion-tailed macaque (Macaca silenus) is demonstrating unexpected resilience, with populations holding steady and even increasing within fragmented landscapes of the Western Ghats.

  • Key Characteristics and Habitat:

  • The lion-tailed macaque is an endangered, highly arboreal primate endemic to the evergreen forests of the Western Ghats.

  • Historically, it was believed their survival depended entirely on large, continuous tracts of undisturbed forest due to their reliance on complex canopies.

  • Principal population strongholds include the Nilgiri-Silent Valley landscape, the Anamalai-Parambikulam complex, Karnataka's Sharavathi Valley, and the Agasthyamalai ranges.

  • Findings on Resilience:

  • Long-term demographic studies in Tamil Nadu’s Anamalai landscape (Valparai plateau) indicate that macaque troops have survived in small plantation-embedded rainforest fragments for over 40 years.

  • This survival is driven by behavioral plasticity: -

  • The macaques are adapting by using the ground more frequently, crossing roads, and occasionally exploiting cultivated crops or human food waste.

  • Survival in these altered environments is also supported by ecological lifelines like remnant canopy patches, native fruiting trees, and targeted conservation measures like canopy bridges.

  • Key Threats and Challenges:

  • Despite showing adaptability, the species remains fragile, with only a few thousand individuals left.

  • Habitat fragmentation severely disrupts dispersal patterns and genetic exchange, leading to long-term genetic isolation that threatens reproductive success.

  • Living in human-modified landscapes exposes them to new mortality risks, including vehicle collisions, electrocution from power lines, and attacks by feral dogs.

  • Historical Significance:

  • It became a symbol of the Silent Valley movement, which successfully halted a proposed hydroelectric project to save its pristine habitat, leading to the creation of Silent Valley National Park.