Silent Valley National Park - Fauna
Mammals
Mammals (formally Mammalia) are members of a class of
air-breathing vertebrate animals characterized by the possession of endothermy,
hair, three middle ear bones, and mammary glands functional in mothers with
young. Most mammals also possess sweat glands and specialised teeth, and the
largest groups of mammals, the placentas, have a placenta which feeds the
offspring during gestation. The word "mammal" comes from the Latin
mamma ("breast"). All female mammals nurse their young with milk
which comes out from special glands, the mammary glands.
There are at least 34 species of mammals at Silent Valley including the threatened lion-tailed macaque, Niligiri langur, Malabar giant squirrel, Nilgiri
tahr, Peshwa’s bat (Myotis peshwa) and hairy-winged
bat. There are nine species of bats, rats and mice.
Distribution and demography of all diurnal primates were studied in Silent Valley National Park and
adjacent areas for a period of three years from 1993 to 1996. Fourteen troops
of lion-tailed macaque, eighty-five troops of Nilgiri
langur, fifteen troops of bonnet
macaque and seven troops
of Hanuman langur were observed.
Of these, the Nilgiri langur was
randomly distributed, whereas the lion-tailed macaque troops were confined to
the southern sector of the Park. Bonnet macaques and Hanuman langurs were
occasional visitors. The Silent Valley forest remains one of the most
undisturbed viable habitats left for the endemic and endangered primate’s
lion-tailed macaque and Nilgiri langur.
The tiger, leopard (panther), leopard
cat, jungle
cat, fishing
cat, common
palm civet, small Indian civet, brown palm civet, ruddy
mongoose, stripe-necked mongoose, Dhole, clawless
otter, sloth
bear, small Travancore flying squirrel, Indian pangolin (scaly
anteater), porcupine, wild
boar, sambar, spotted
deer, barking
deer, mouse
deer, elephant and gaur also live here.
Herpetofauna
There are at least 730 identified species of insects in
the park. The maximum number of species belongs to the orders Lepidoptera and Coleoptera. Many unclassified species have been collected and
there is a need for further studies.
33 species of crickets
and grasshoppers have been recorded
of which one was new. 41 species of true
bugs (eight new) have been recorded. 128 species
of beetles including 10 new species have been recorded.
Over 128 species of butterflies and 400 species of moths live here. A 1993 study found butterflies
belonging to 9 families. The families Nymphalidae and Papilionidae contained the maximum number of species. 13
species were endemic to South India, including 5 species having protected
status. Seven species of butterflies were observed migrating in a mixed swarm of thousands of butterflies
towards the Silent Valley National Park.
In one instance an observer noted several birds attempting
to catch these butterflies. The bird species included the pied
bush chat Saxicola
caprata, Nilgiri
pipit Anthus
nilghiriensis, Tickell's leaf warbler Phylloscopus affinis, greenish
warbler Phylloscopus trochiloides and the Oriental white-eye Zosterops palpebrosa.
At least 500 species of earthworms and leeches have also been identified in the park.
The term herpetofauna encompasses both reptiles and
amphibians, and herpetology is the branch of zoology involved in the study of this
diverse group of vertebrates, covering poikilothermic, ectothermic tetrapods, excluding fish. It is home to 48
reptile and 29 amphibian species.
Butterflies
A butterfly is a mainly day-flying insect of the order
Lepidoptera, which includes the butterflies and moths. Like other
holometabolous insects, the butterfly's life cycle consists of four parts: egg,
larva, pupa and adult. Most species are diurnal. Butterflies have large, often
brightly coloured wings, and conspicuous, fluttering flight.
Butterflies comprise the true butterflies (super family
Papilionoidea), the skippers (superfamily Hesperioidea) and the
moth-butterflies (superfamily Hedyloidea). All the many other families within
the Lepidoptera are referred to as moths. Butterflies exhibit polymorphism,
mimicry and aposematism. Culturally, butterflies are a popular motif in the
visual and literary arts.
Birds
Birds (class Aves) are feathered, winged, bipedal,
endothermic (warm-blooded), egg-laying, vertebrate animals. The fossil record
indicates that birds evolved from theropod dinosaurs during the Jurassic
period, around 160 million years (Ma) ago. Modern birds are characterized by
feathers, a beak with no teeth, the laying of hard-shelled eggs, a high
metabolic rate, a four-chambered heart, and a lightweight but strong skeleton.
Birdlife International lists 16 bird species in Silent Valley as
threatened or restricted:- Nilgiri wood-pigeon, Malabar
parakeet, Malabar grey hornbill, white-bellied treepie, grey-headed bulbul, broad-tailed
grass bird, rufous
babbler, Wynaad laughing
thrush, Nilgiri laughing thrush, Nilgiri blue robin, black-and-rufous flycatcher, Nilgiri flycatcher, white-bellied blue-flycatcher, crimson - backed sunbird and Nilgiri
pipit.
Rare bird species found here include the Ceylon
frogmouth and great Indian hornbill. The 2006 winter bird survey discovered the long-legged buzzard, a new species of raptor at Sispara, the park's highest peak. The survey found 10
endangered species recorded in the IUCN
Red List including the red winged crested cuckoo, Malabar pied hornbill and pale
harrier.
The area is home to 15 endemic species including
the black-and-orange flycatcher. It recorded 138 species of birds including 17 species
that were newly observed in the Silent Valley area. The most abundant bird was
the black bulbul.
