Modelling Population Viability of Three Independent Javan Gibbon (Hylobates moloch) Populations on Java, Indonesia

Javan gibbons (Hylobates moloch) face a high risk of local extinction within 100 years due to persistent hunting and deforestation, according to a population viability analysis conducted using the VORTEX modelling software. The study assessed three independent populations—two in protected areas (Ujung Kulon National Park and Halimun-Salak National Park) and one unprotected (Dieng Mountains)—which together hold over half of Java's remaining gibbons. Findings indicate that if current threats persist, all populations could face extinction, while eliminating these pressures could ensure long-term survival with sustained genetic diversity. The research underscores the critical need for enhanced conservation measures, including stricter protection against illegal wildlife trade and habitat degradation.

Smith, J. H., King, T., Campbell, C., Cheyne, S. M., & Nijman, V. (2018). Modelling Population Viability of Three Independent Javan Gibbon (Hylobates moloch) Populations on Java, Indonesia. Folia Primatologica, 88(6), 507–522. https://doi.org/10.1159/000484559