Genetic variability in mtDNA of the silvery gibbon: Implications for the conservation of a critically endangered species

The silvery gibbon (Hylobates moloch), endemic to the island of Java, relies on closed-canopy lowland evergreen forest for its survival. Because Java has lost over 91% of its original forest, silvery gibbons currently occupy small, isolated forest fragments and are threatened with extinction. To contribute to a comprehensive conservation strategy for this species, we analyzed the mtDNA control region of 31 silvery gibbons representing most remaining populations. Our results suggest the presence of at least two genetically differentiated lineages: a "western" lineage, represented by the largest remaining natural population in Gunung Halimun National Park and a "central" lineage, consisting of smaller, more isolated populations in and around the Gunung Masigit/Simpang/Tilu complex, Gunung Gede/Pangrango, and Gunung Slamet. These two lineages, at a minimum, represent different management units that should, except in the most dire circumstances, be managed separately.