KOLLAM,
The Hindu, November 28, 2015
The lion-tailed macaques (
Macaca silenus
) which are found only in forests from the central to the southernmost
tip of the Western Ghats are not a single entity. A recent scientific
study has shown that the 4,000 monkeys that survive now comprise two
genetically different populations.
The most prominent
break in the Western Ghats is the Palghat gap, which is about 40 km
wide. South of the gap, the macaque habitats are highly fragmented,
compared to the habitats in the contiguous forests in the north. The
study shows that the lion-tailed macaques living north of the Palghat
gap are genetically different from those living in the south.
The
study says that although the lion-tailed macaque has a relatively wide
range south of the gap, its area of occupancy is small and severely
fragmented. Small populations in isolation, especially in fragmented
landscapes, are known to lose genetic variability, suffer from
inbreeding depression, and become genetically differentiated among
themselves.
The finding is that those in the south
have low mitochondrial DNA diversity compared to those in the north.
“These populations can be considered as separate conservation units and
should be treated separately in captive breeding programmes. Any
reintroductions to the wild should be done after ascertaining the
correct geographic origin of the individual.”
The
study recommends that some of these isolated fragments be connected by
planting food trees that would establish canopy corridors between them
to facilitate gene flow.
The study, ‘Prehistoric and
recent vicariance events shape genetic structure and diversity in
endangered lion-tailed macaque in the Western Ghats: Implications for
conservation,’ published in
Plos One
, a peer-reviewed open access scientific journal, on November 11, was
conducted by Muthuvarmadam S. Ram, Minal Marne, Ajay Gaur, Honnavalli N.
Kumara, Mewa Singh, Ajith Kumar, and Govindhaswamy Umapathy.
It
was jointly funded by the Department of Biotechnology under the Union
Ministry of Science and Technology and the Central Zoo Authority of
India.
The study was carried out in the forests of
Aghanashini, Karkala, Kundapur, and Kudremukh in Karnataka, Muthanga,
Vazhikkadavu, Silent Valley, Nelliampathy, Kodanad, Vazhachal, Kollam,
and Amboori in Kerala, and Anamalai, Meghamalai, and Kalakkad in Tamil
Nadu.
