Birds of
lower Palni Hills, Western Ghats, Tamil Nadu
Tharmalingam Ramesh 1,
J. Peter Prem Chakravarthi 2, S. Balachandran 3 &
Riddhika Kalle 4
1,4Wildlife Institute of India, Chandrabani, P.O. Box 18, Dehra Dun, Uttarakhand 248001,
India
1,2,3 Bombay Natural History Society, Hornbill House, Shaheed
Bhagat Singh Road, Mumbai, Maharashtra 400001, India
4 B-1, Prerana
Mandir, S.V. Road, Santacruz(W), Mumbai, Maharashtra400054, India
Email: 1 ramesh81ngl@gmail.com
(corresponding author), 2 peterpremcj@gmail.com, 3 bnhsbala@rediffmail.com,4 riddhikalle@gmail.com
Date of publication
(online): 26 November 2012
Date of publication (print): 26 November 2012
ISSN 0974-7907 (online) | 0974-7893 (print)
Editor: Kumaran Sathasivam
Manuscript details:
Ms # o3051
Received 02 January 2012
Final received 14 May 2012
Finally accepted 10 October 2012
Citation: Ramesh, T., J.P.P.
Chakravarthi, S. Balachandran & R. Kalle (2012).
Birds of lower Palni Hills, Western Ghats, Tamil Nadu. Journal of Threatened
Taxa 4(14): 3269–3283.
Copyright: © Tharmalingam Ramesh,
J. Peter Prem Chakravarthi, S. Balachandran & Riddhika Kalle 2012. Creative Commons Attribution 3.0
Unported License. JoTT allows unrestricted use of this article in any medium
for non-profit purposes, reproduction and distribution by providing adequate
credit to the authors and the source of publication.
Author Details: Dr.
Tharmalingam Ramesh is broadly interested in mammal and
bird ecology. He has conducted research on migratory birds, water birds,
mist-netting, bird-ringing and birds of tropical forests in India. Presently he
is a research fellow at the Wildlife Institute of India, studying predator-prey
ecology in the Western Ghats. Mr. J.P.P.
Chakravarthy is a Sr. Project Officer in the Western Ghats Landscape
Program at WWF, studying the population of tiger, since 2010. Dr. S. Balachandran is
a Sr. Scientist at BNHS, studying migratory water birds and their movements
across India. Ms. Riddhika Kalleis pursuing her PhD at the Wildlife Institute of India (WII), on small
carnivore ecology in Mudumalai Tiger Reserve. She worked as a research fellow
at WII on predator-prey ecology in the Western Ghats.
Author Contribution: TR
wrote the manuscript, designed the study, conducted field surveys, collected
and analysed the data, JPPC and SB, designed the study, conducted field surveys
and collected data, RK helped with the writing and editing of the manuscript.
Acknowledgements:The Ministry of Environment and Forest, Government of India is greatly
acknowledged for funding our research activities in the Palni Hills. We
thank the Director, Bombay Natural History Society and Tamil Nadu Forest
Department for granting us the permission to carry out our study in the Palni
Hills. We are indebted to our field assistants and forest department staff for
their help and logistic support.
urn:lsid:zoobank.org:pub:04D8DDC9-2797-4E38-BA36-72C91C3F94EE
Abstract: The current altitudinal distribution and breeding
observations on birds of lower Palni Hills, Western Ghats were documented by
conducting road transects, opportunistic surveys including trail walks and mist
netting. A total of 196 species
belonging to 63 families were recorded during the study. The Accipitridae family was foremost in
species richness, followed by Cuculidae and Muscicapidae, Picidae, Timaliidae
and other families. Altitudinal
distribution of birds was higher between 600 and 900 m. The general patterns of the decreasing species
richness with increasing altitude were observed in mid and upper Palnis. This could be probably because the lower
Palnis have more deciduous and scrub forest which can support high food
availability. Resident and migrant
species made up to 87.76% and 12.24% of the community, respectively. We recorded a species that was threatened,
three nearly threatened, and five endemic to the Western Ghats. Most of the endemics were confined to
the higher altitudes due to the presence of moist evergreen and high altitude
montane forests and grasslands. In total, 51 breeding bird observations were
recorded. Interestingly, the variation in the breeding season of
some birds was noticed with respect to earlier studies. Overall, our study illustrated useful
information on bird community in this region which serves as
a baseline for future monitoring programs.
Keywords: Altitudinal distribution, breeding birds, lower Palni
Hills, Western Ghats.
The publication of this article is
supported by the Critical Ecosystem Partnership Fund (CEPF) -- a joint
initiative of l’Agence Française de Développement, Conservation International,
the Global Environment Facility, the Government of Japan, the MacArthur
Foundation and the World Bank.
For
figures, tables -- click here
Introduction
Birds are ideal bioindicators and useful
models for studying a variety of environmental problems, hence the condition of
local landscape must be investigated to identify crucial determinants of the
bird community structure for avian conservation (Kattan & Franco 2004). Describing and explaining spatial
patterns in species diversity are crucial steps in conserving global
biodiversity (Lee et al. 2004) as the number of bird species inhabiting various
altitudinal belts or ‘life zones’ (Ali 1949) depend on climatic changes accompanied
by corresponding changes in vegetation. Studies on species distribution along elevational gradients are
essential to understand principles of community organisation and species
conservation. The Western Ghats, identified as one of the biodiversity hotspots
in the world, is a 1600-km long chain of mountain ranges running parallel to
the western coast of the Indian peninsula (Pascal 1988). Among the three distinct sections of the
Western Ghats, the south-eastern region has one of the richest tropical forests
in the country. The Western Ghats
has nearly 508 bird species of which 3.5% are endemic out of more than 1200
species in India (Rajmohana & Radhakrishnan 2008). Apparently the Indian bird population
has been dwindling due to direct/indirect impact from increasing human
population (Balachandran et al. 2005), habitat loss, fragmentation, and severe
biotic pressure, necessitating documentation of the current status of bird
species for future monitoring and conservation (Islam & Rahmani 2004). Bird community evaluation has become an
important tool in biodiversity conservation and for identifying conservation
actions in areas of high human pressure (Kremen 1992; Shafiq et al. 1997;
Chettri et al. 2001; Ramesh et al. 2011).
The avifaunal diversity of Palni Hills has
been documented by various authors (Nichols 1937; Fairbank 1877; Terry 1887)
and specific ecological studies were carried out in the higher altitudes
(Balachandran 1998; Robin & Sukumar 2002; Balachandran et al. 2005;
Somasundaram & Vijayan 2008). Apart from anecdotal
observations on birds (Blanford 1867; Foulkes
1904; Navarro 1955, Fuller 1958; Surendran 1973; Ananthasubramaniam 1979; Narayana 1979; Steele 1990), few studies involve bird
ringing techniques (Balachandran 1992) and
a few have been monitored at low altitudes (Shahabuddin 1997). However, little is known
about the avifaunal status in the lower Palni Hills, from the foothills to an
altitude of 900m above mean sea level. In order to fill up the lacunae, a short term survey was carried out to
document the avifaunal altitudinal distribution and breeding observations in
the lower Palni Hills.
Materials and Methods
Study Area
Palni Hills is in the south-eastern part
of the Western Ghats Hotspot in Tamil Nadu. It lies between 10.10–10.260N
and 77.140–77.520E covering an area of c. 2400km2(Image 1). It is one of the
important global biodiversity hotspots with high endemism. The Palni Hills have three well marked
topographic divisions, namely the lower (300–900 m), mid (>900–1800
m) and high Palnis (>1800–2500 m) for research and administrative
purposes (Balachandran et al. 2005). Perennial
rivers such as Mulayar and Arunganal and semiperennial rivers like Thalaiyar
(Rat-tail Falls) (Balachandran et al. 2005) and Iruttar, are important water
sources for the Manjalaar reservoir (situated at the foothills of 300m
elevation) and it is used for irrigation purposes in the lower Palnis. The
minimum recorded temperature is about 8.30C and the maximum goes up
to 230C. The annual average
precipitation ranges from 800–1900 mm in the Palnis (Balachandran et al.
2005). There are four seasons;
Winter (December–March), Summer (April–June), southwest monsoon
(June–September) and northeast monsoon (October–November). The climate is sub-tropical with major
vegetation types broadly classified into scrub forest, moist and dry deciduous
forest of low and mid elevations and montane evergreen forest of high
elevations (Champion & Seth 1968). In addition to birds, important mammals found in Palni are Sambar Rusa
unicolor, Muntjac Muntiacus muntjak, Wild Pig Sus scrofa,
Indian Chevrotain Tragulus meminna, Gaur Bos gaurus, Four-horned
Antelope Tertracerus quadricornis, Nilgiri Tahr Nilgiritragus
hylocrius, Tiger Panthera tigris, Leopard Panthera pardus,
Dhole Cuon alpinus, Striped Hyena Hyaena hyaena, Golden
Jackal Canis aureus and Grizzled Giant Squirrel Ratufa
macroura (Prater 1971).
The Manjalaar reservoir forms an important
water body for water birds. Some
parts of the river delta in lower Palnis constituted an endemic eco-region with
very rare and endangered plants and animals of India but now it has been
modified with cultivation of Silk Cotton Ceiba pentandra, TeakTectona grandis, Mango Mangifera indica, Coffee Coffea arabica and
Coconut Cocos nucifera. Expanding agricultural, urban, productive and developmental activities
currently threaten to take over Palni’s natural habitat and pose a threat to
its preservation due to large-scale deforestation. With human disturbance, the riparian
forest patch is being converted on the slopes as a complex mosaic of
plantations such as mango groves, groundnut and pulses, secondary and native
forests. This work is part of a
long term research project “Revaluation of bird community structure of Palni
Hills with special reference to endemic and threatened species” (Balachandran
et al. 2005).
Field survey
We recorded sightings of birds in the
lower Palnis from December 2004 to July 2005 and documented the occurrence,
altitudinal distribution and breeding. The highly mountainous terrain made it impossible to lay line
transects. Instead, we conducted
road transects in the lower Palnis from Palni Hill Conservation Council (PHCC),
Kamakapatti to Poolathur road junction (16.5km). The road was divided into six segments
of 2.5km each, including a segment of 4km where each segment was sampled twice
every month in the mornings (06:00–10:00 hr) and evenings
(16:00–18:30 hr). In
addition, opportunistic road surveys, trail walks and mist netting were
conducted to record bird species within a 3km radius from the regular road
transect area. The five mist-nets
were operated opportunistically at dawn from 06:00–09:00 hr and in the
evenings from 15:00–18:00 hr. Mist nets were visited every hour to check the trapped birds for
collection and identification. All
nets were made of black nylon mesh size, 36mm with dimensions 2m high by 6m
long.
Results
A total of 196 species belonging to 63
families were recorded during the study (Table 1). All observations listed in Table 1 have
already been published in the survey report (Balachandran et al.
2005). Accipitridae
family showed highest species richness (18 species), followed by Cuculidae and
Muscicapidae (10 species each), Picidae, Timaliidae, (eight species each),
Phasianidae and Pycnonotidae (seven species each), Ardeidae, Cisticolidae,
Columbidae, Dicruridae, Estrildidae, Motacillidae and Nectariniidae (five
species each) and other families (less than five species each). Of the recorded species, 87.76% were
resident and 12.24% migrants. In
terms of frequency of observations, the majority of species were found to be
common (74.49%), followed by uncommon (19.90%) and rare (5.61%) species. In
terms of altitude, species and families were seen between >600–≤700 m
and >700–900 m respectively. The number of bird species observed in each altitude zone were
128–≤400m, 122–>400 to ≤ 500, 121–>500 to ≤600,
139–>600 to ≤700, 131–>700 to ≤800 and 130–>800 to ≤900. During the study, a threatened species,
three nearly threatened and 192 least concerned species were also
recorded. Among all the species,
five were endemic to the Western Ghats.
Breeding
observations
Breeding
observations of 51 bird species are given as follows:
Shikra Accipiter badius: In
the lower Palnis, (c. 350m altitude) a mating pair was sighted on 3 February
2005. On 25 February, its nest was
noticed with an egg on an Ailanthus excelsa tree and was seen with two
additional eggs on 8 March. On 25
March the hatched eggshells were seen under the tree but the hatchlings were
taken away by graziers for consumption. The nest was noticed again with a single egg on 5 April 2005, which was
predated later. The other nest was
located in early March on Acacia catechu near the arboretum of PHCC. It had two eggs and both fledged
successfully on 2nd May 2005.
Changeable Hawk-eagle Spizaetus cirrhatus: During the transect count on 24 March 2005 a nest was located
containing a newly hatched chick with fluffy white down feathers and black beak
on a tree located in a ravine of the riparian forest at an altitude of
732m. The nestling, being a
singleton, was monitored continuously until fully grown and fledged. The nest was a large platform of sticks
and twigs with a central depression lined with fresh green leaves constantly
renovated to protect the nestling from direct sunlight. The nest was located at a height of
about 15m from the ground on a 30m tall tree having a dbh (diameter at breast
height) of 132cm.
Painted Spurfowl Galloperdix lunulata: A male with a single chick with dark brown
down feathers was seen foraging on a rocky slope interspersed with grass and
bush, near the road at 410m altitude on 14 June 2005. It was speculated that both parents were
involved in parental care.
Grey Junglefowl Gallus sonneratii:Noticed with three chicks on 25 March 2005, at 781m altitude.
Indian Peafowl Pavo cristatus: Three juveniles were recorded on 11 December 2004 at 350m altitude and
may have possibly hatched in early November.
Little Brown Dove Streptopelia senegalensis: Three nests were observed in the Lower Palnis. At 320m altitude the nest was made up of
short grasses laid on the ground under Dodonaea viscosa bush. Another nest was located on an Acacia
planifrons tree on 07 April 2005. A pair of eggshells from another nest
was collected near Carissa sp. shrub on 14 June 2005.
Spotted Dove Streptopelia chinensis: On 2
July 2005, a nest with two eggs was located on the lower fork of a Teak Tectona
grandis tree at about 3m from the ground at 320m altitude.
Plum-headed Parakeet Psittacula cyanocephala: Two juveniles with an adult were seen at 600m altitude on 7 April 2005.
Sirkeer Malkoha Phaenicophaeus leschenaultii: A juvenile was seen perched on a Diospyros
montana tree at 350m altitude in mid April and another juvenile
accompanying an adult was noticed in early June 2005.
Greater Coucal Centropus sinensis: This
species was seen carrying food material in mid June at 320m altitude.
Spotted Owlet Athene brama: The
nest was seen on a rooftop of a house at 300m altitude. Two broods were noticed in the same
nest, one during February and another in late April. Both the broods were observed with eggs,
but on the next day, all eggs rolled out of the nest to the ground.
Common Indian Nightjar Caprimulgus asiaticus: Two juveniles accompanying an adult were
seen along the mud path at 320m altitude on 5 May 2005. A juvenile was caught in a mist net in
early December.
White-breasted Kingfisher Halcyon smyrnensis: A nest was located on the roadside bank at 630m altitude, during May
2005.
Blue-bearded Bee-eater Nyctyornis athertoni: On 29 April 2005, a nest was located along
the roadside along a gentle downward slope at a height of 850m altitude. The nest was about 3–4 cm in
diameter and more than 1.5m deep.
Small Bee-eater Merops orientalis: On 24 April 2005, at 320m altitude a nest was observed in a
small earthen structure constructed for rainwater harvesting. The nest hole was about two inches in
diameter and both adults were seen hunting insects and feeding their
nestlings. Many insect heads were
seen scattered at the entrance of the nest.
Chestnut-headed Bee-eater Merops leschenaulti: In Lower Palnis, more than five nests were
seen on a roadside sand bank on 17 April 2005 at 650m altitude. These nests were horizontal tunnels
drilled into the sand bank. An
active nest was located and two eggshells were seen near the nest hole.
Malabar Grey Hornbill Ocyceros griseus: Two nests were noticed during March 2005 at an altitude of c.
800m. A nest-hole was found on a
horizontal branch of a large Buchanania axillaris tree at a height of
about 20m from the ground and the other was on the trunk of a large tree with
10 nesting holes. In both the
nests, the adult male was seen feeding the incarcerated inmates with black
berries and insects. On 23 June
2005, two fledglings flew across the road.
Red-rumped Swallow Hirundo daurica: In the lower Palnis, three nests were
located. Of them, two were
constructed under road culverts, one at 415m altitude and the other at 552m
altitude. The third nest was seen
on the ceiling of an abandoned building at 320m with shells of two eggs found
on the ground. Only a single nest
was seen with two nestlings.
Large cuckoo-shrike Coracina macei: A nest was noticed in the lower Palnis
during early May 2005 at 604m altitude. The nest was seen on the fork of a Tectona grandis tree at a
height of about 20m. The nest was
built by peeling the fibres from a Commiphora caudata tree. The nest was not found after the rains.
Small Minivet Pericrocotus cinnamomeus: Although the nest was not seen, both male and female were seen carrying
food in mid April 2005 in the scrub forests at 320m altitude.
Scarlet Minivet Pericrocotus flammeus: On 24 March 2005, a well-camouflaged nest
lined with lichen was observed on Tectona grandis and the female was
seen incubating the eggs. The male
fed the incubating female a moth.
Black-crested Bulbul Pycnonotus melanicterus gularis: On 20 January 2005, a nest was located at 789m altitude. The bird was seen plucking leaves for
nest construction and taking them onto a tree.
Red-whiskered Bulbul Pycnonotus jocosus: Although no nests were located, two juveniles were caught in a mist
net, at an altitude of 320m on 1st November 2004. As this species is very rare in the
lower altitudes (up to 400m), the juveniles caught might be undergoing a
‘juvenile dispersal period’.
Yellow-throated Bulbul Pycnonotus xantholaemus: Collection of nest materials by this bird was noticed on 10 April 2005
and 9 June 2005.
White-browed Bulbul Pycnonotus luteolus: A nest was located on 18 April 2005 on Celtis sp. tree at
about 4m from the ground at 630m altitude.
Oriental Magpie-robin Copsychus saularis: On 7 May 2005, a bird was observed in the thick undergrowth with an
insect in its mouth at 591m altitude.
White-rumped Shama Copsychus malabaricus: A nest was located on a short dead stump
of a tree on an inaccessible slope at 410m altitude. Both the birds were seen frequenting the
site as if they were feeding young ones.
Indian Robin Saxicoloides fulicata: The bird was seen carrying food to an
inaccessible bush. Such sightings
were made at various altitudes from 320–600 m altitude from mid May till
late June.
Rufous-bellied Babbler Dumetia hyperythra: A nest with four nestlings was located at about 350m on 30 April 2005
and all the nestlings fledged on 2 May 2005.
Yellow-eyed Babbler Chrysomma sinense: A nest with two nestlings was located on
17 November 2004.
White-headed Babbler Turdoides affinis: A nest with three eggs was located on a fork of Carissa sp.bush at about 1.5m from the ground on 19 February 2005 at 320m altitude. The eggs were predated and the nest was
abandoned.
Jungle Prinia Prinia sylvatica: Three nests were located in the scrub jungle between altitudes 300 and
400 m from late February to May. Out of the three nests, two had nestlings (two and three) and the other
nests with three eggs were abandoned later. The breeding season does not correspond
with the months (April to September) as indicated by Ali & Ripley (1983).
Plain Prinia Prinia inornata: A nest with two nestlings was located during the first week of December
2004 at 320m altitude. Both the
chicks fledged successfully.
Common Tailorbird Orthotomus sutorius: A total of 23 juveniles were ringed from
September to June at 320m altitude.
Asian Brown Flycatcher Muscicapa dauurica: A juvenile was noticed in a mixed foraging
flock at 665m altitude on 7 June 2005. An adult was noticed feeding a juvenile
at 640m altitude on 17 June 2005.
Tickell’s Blue-flycatcher Cyornis tickelliae: In the Lower Palnis, two nests with nestlings each, were located
between 564 and 648 m altitudes respectively. Both the nests were placed in rocky
clefts along the roadside. The first
nest was located in late April 2005 which was well camouflaged with fern leaves
and placed at about 5m from the ground and the next was located in late June at
about 4m from the ground.
Tickell’s Flowerpecker Dicaeum erythrorynchos: A male and female were observed collecting
nest materials on 22 and 29 January 2005 at 550m altitude in the dry deciduous
forests of Lower Palni Hills.
Thick-billed Flowerpecker Dicaeum agile: Two nests were observed. A nest with two nestlings was being fed by both adults on an Acacia
planifrons tree at c.3m from the ground on 29 January 2005 at 420m
altitude. The other was located on an Albizzia lebbeck tree at c.5m from
the ground on 12 February 2005 at 580m altitude.
Purple-rumped Sunbird Nectarinia zeylonica: Four nests were recorded, one each in January and February and two in
March. All nests were abandoned.
Purple Sunbird Nectarinia asiatica: Ten nests were seen with two eggs each in
lower Palnis. Nestlings in four
nests fledged successfully, two nests were abandoned and the other two nests
could not be monitored. A nest was
located with two eggs on 28 April at 320m altitude in Acacia leucophloea tree,
but both the hatchlings succumbed to rain on 3 May 2005.
Loten’s Sunbird Nectarinia lotenia: At 462m altitude a nest was located on 11
April 2005 at c. 6m from the ground on a tree. Both the adults were seen frequenting
the nest.
Oriental White-eye Zosterops palpebrosus: In lower Palnis, construction of two nests was observed on 24 March at
altitudes 738 and 744 m. One was at about 3m from the ground on a Celtis sp. tree but was later damaged by a vehicle passing over. The other was at a
height of about 8m from the ground on a tree.
White-rumped Munia Lonchura striata: Two
nests were recorded on 2 December 2004. One was located with seven nestlings on
a tree about 3m from the ground. One had an egg but no eggs were found in the other. Both the nests were abandoned.
White-throated Munia Lonchura malabarica: A nest with three eggs was located on an Acacia
planifrons tree in late November 2005.
Common Myna Acridotheres tristis: A nest was constructed on the roof of a building at 320m altitude during
mid June and the the incubating eggs were seen till early July 2005.
Southern Hill-myna Gracula religiosa indica: A nest was observed at 800m altitude in Lower Palnis on Chukrasia
tubularis tree at c. 5m from the ground during late March 2005. Reuse of the nest by the pair was
observed in March and the second brood was seen in July 2005.
Black-headed Oriole Oriolus xanthornus: Collection of nest material was seen in late April and a juvenile was
observed being fed by its parents in mid June 2005 at 619m altitude.
Black Drongo Dicrurus macrocercus: On 24 March 2005, a nest with two eggs was located on Acacia
leucophloea tree and both the eggs hatched on 5 April 2005.
Greater Racket-tailed Drongo Dicrurus paradiseus: In the lower Palnis, a nest with an incubating female was seen during
mid April at 762m altitude on a tall tree c. 20m from the ground.
Indian Treepie Dendrocitta vagabunda: A mating pair was sighted in mid June 2005
at 360m altitude. A juvenile was
seen begging for food from an adult at 630m altitude on 6 July 2005.
Jungle Crow Corvus macrorhynchos: A
nest was located during mid-June on Azadirachta indica tree at a height
of 7m from the ground.
Discussion
Species richness generally decreases with
increasing elevation (Begon et al. 1996). Bird distribution and abundance varies with habitat (Jayapal et al.
2007; Ramesh et al. 2011), climatic condition, food resource and evolutionary
history of the area (Jayson 1994). The species richness recorded was lowest in the upper Palnis (n=99) and
mid Palnis (n=130) (Balachandran et al. 2005) in comparison to lower
Palnis. This was probably because
lower Palnis has more deciduous and scrub jungle which may support high food
availability. Thus, in this
heterogeneous matrix of habitat it is essential to maintain and conserve intact
forests. In Kalakad-Mundanthurai
Tiger Reserve, Raman et al. (2005) revealed that bird community composition
significantly correlated with elevation and tree species composition of sites,
indicating the influence of deterministic factors on bird community
structure. Resource abundance and
availability are described as the most important factor in determining the
community structure (Recher & Davis 2002). The bird families Accipitridae,
Cuculidae, Muscicapidae, Picidae, Timaliidae, Phasianidae, Pycnonotidae, Ardeidae,
Cisticolidae, Columbidae, Dicruridae, Estrildidae, Motacillidae and
Nectariniidae are sufficiently abundant and thus considered to be
characteristic of resource availability in this region (Balachandran et al.
2005). Endemic bird species were
less in the lower Palnis than mid and upper Palnis. Most of the endemics were confined to
the higher altitudes due to the presence of moist evergreen and high altitude
montane forests and grasslands (Pramod et al. 1997; Vijayan & Gokula
2006). The extensive deciduous and
scrub forests were not used much by the endemics though the habitats are
generally richer in bird species than humid evergreen and montane forests, when
equal areas are compared (Daniels et al. 1991, 1992). Similarly, the common and resident birds
are abundant in lower Palnis. More
bird species and families were found between 600 and 900 m altitude. This is probably related to the presence
of mixed vegetation types at these altitudes. By comparing the number of species
present in lower Palnis with earlier studies by Balachandran et al. (2005), and
Somasundaram & Vijayan (2008) in mid and upper Palnis the species richness
was higher in the lower altitude than the higher altitude. Similarly, most studies have shown a
general pattern of decreasing species richness with increasing altitude believed
to mirror the well-recognised latitudinal gradient in species richness
(MacArthur 1972; Bachman et al. 2004, Raman et al. 2005).
Palni Hills is located in the southeastern
Western Ghats and is well known for its high endemism (Rajmohana &
Radhakrishnan 2008). Though these
hills are highly significant for the seven high altitude endemic species namely
Nilgiri Wood-Pigeon, Grey-breasted Laughing Thrush, Black-and-Orange
Flycatcher, Nilgiri Flycatcher, Broad-tailed Grass-Warbler, White-bellied
Shortwing and Nilgiri Pipit, they are found above 1500m (Balachandran et al.
2005; Somasundaram & Vijayan 2008) despite the lower Palnis having a
threatened species, three nearly threatened and five endemic species. In total, 9 and 11 endemics, 3 and 2
Vulnerable and 5 and 4 Near Threatened birds were recorded in mid and upper
Palnis, respectively. The Indian
Rufous Babbler Turdoides subrufus and the Small Sunbird Nectarinia
minima are the two endemics seen in all the three divisions of Palnis. It is evident that Palni hills is a
significant site due to the high congregation of threatened and endemic bird
species as referred by the Important Bird Area (IBA) (Islam & Rahmani
2004). This site has been selected
as an IBA site on the basis of the presence of globally threatened species with
a significant percentage of restricted range species, and some biome-restricted
species (Islam & Rahmani 2004). The presence of endemic and threatened species indicates the conservation
importance of the study site. All
the endemic species observed have already been recorded in the hill ranges of
Palni Hills (Fairbank 1877; Terry 1887; Nichols 1937) while some that appeared
to be rare like the Indian Rufous Babbler, Blue-winged Parakeet Psittacula
columboides and Malabar Grey Hornbill Ocyceros griseus in Lower
Palnis may be due to habitat fragmentation and degradation. Habitat loss due to anthropogenic
pressure is the greatest threat to most of the Indian birds (Rahmani 2008). Anthropogenic pressures like illegal
encroachment into forest land, livestock-grazing, and harvesting of fuel wood
with huge quantities of minor forest products must be put under control in this
region (Balachandran et al. 2005). Interestingly, variations in the observation of breeding season compared
to Ali & Ripley (1983) was noticed in plain Prinia Prinia
inornata, known to breed from March to July, was found breeding in the
first week of December. Its nest
was located with two nestlings. Both nestlings fledged successfully. Shikra Accipiter badius breeds
from March to June but it also bred earlier in February. Spotted Owlet Athene brama breeds
in November and March but the second brood was observed in April. Common Iora Aegithina tiphiausually breeds from January to August, but it was noticed breeding in November
along with the observation of a nest with juveniles. Baya Weaver Ploceus philippinususually breeds from June to September but it was seen breeding in October.
Our study illustrated useful breeding
observations of birds in the Palni Hills. The protection of Important Bird Areas contributes not only to bird
conservation but even the biodiversity of this highly endangered ecosystem as a
whole (Islam & Rahmani 2004). Since we documented the occurrence, altitudinal distribution and
breeding observations, we felt that eight months were sufficient to bring out
useful information on the aforementioned aspects. However, we agree that the short term
field study was a limitation and definitely a long term study would bring out
robust ornithological information on Palni Hills. This study generated baseline data on
bird species occurrence along an altitudinal gradient in the lower Palni
Hills. Large scale habitat changes
occurring globally fulfil endless human needs, habitat destruction, fragmentation
and degradation necessitates further assessment on the impact of anthropogenic
changes on birds (Brash 1987; Whitten et al. 1987; Khan et al. 1993). To maintain the bird community
structure, further habitat exploitation must be minimised by regulating human
activities (Johnsingh & Joshua 1994). The data gathered from this study serves to be important in developing
future conservation and management programs, which will identify priority areas
for long-term persistence of bird communities.
References
Ali,
S. (1949). Indian Hill Birds. Oxford University Press, Bombay, 188pp.
Ali,
S. & S.D. Ripley (1983). Handbook of The
Birds of India and Pakistan—Vol. 6. Second Edition. Oxford
University Press, New Delhi, 462pp.
Ananthasubramaniam,
C.K. (1979). Crows in Kodaikanal. Newsletter
for Birdwatchers 19(7): 11–12.
Bachman,
S., W.J. Baker, N. Brummitt, J. Dransfield & J. Moat (2004). Altitudinal gradients, area and tropical island diversity: an example
from the palms of New Guinea. Ecography 27: 299–310.
Balachandran,
S. (1992). BNHS Bird Ringing activities at Kodai
hills. Newsletter for Birdwatchers 32(7–8): 12–13.
Balachandran,
S. (ed.) (1998). Bird Migration studies in IndiaFinal Report (1980–1992). Phase I: Population Structure and Movement of
Indian Avifauna (1980–1986) Final Report Phase II: Bird Migration
(1987–1992). Final Report. Bombay Natural History Society, Mumbai, 150pp.
Balachandran,
S., A.R. Rahmani, N. Ezhilarasi, S. Babu, J.P.P. Chakravarthy & T. Ramesh
(2005). Revaluation of bird community structure of
Palni Hills with special reference to threatened and endemic species. Final
Report. Bombay Natural History Society, Mumbai, 105pp.
Begon,
M., J.L. Harper & C.R. Townsend (1996). Ecology:
individuals, populations, and communities.Blackwell Science, London, 945pp.
Blanford,
W.T. (1867). On a new species of Callene from
the Pulney Hills in southern India. Proceedings of the Zoological Society of
London 1867: 832–834.
Brash,
A.R. (1987). The history of avian extinction and forest
convertion on Puerto Rico. Biological Conservation 39: 97–111.
Champion,
H.G. & S.K. Seth (1968). A Revised Survey of
the Forest Types of India. Government of India Publication, New Delhi,
404pp.
Chettri,
N., E. Sharma & D.C. Deb (2001). Bird
community structure along a trekking corridor of Sikkim Himalaya: a
conservation perspective. Biological Conservation 102: 1–16.
Daniels,
R.J.R., M. Hegde, N.V. Joshi & M. Gadgil (1991). Assigning conservation value: a case study from India. Conservation
Biology 5(4): 464–475.
Daniels,
R.J.R., N.V. Joshi & M. Gadgil (1992). On
the relationship between bird and woody plant species diversity in the Uttara
Kannada District of south India. Proceedings of the National Academy of
Sciences (USA) 89(12): 5311–5315.
Fairbank,
S.B. (1877). A list of birds collected and observed on
the Palani Hills. Stray Feathers 5: 387–410.
Foulkes,
R. (1904). The Indian edible-nest Swiftlet (Collocalia
fuciphaga) in the Pulney Hills. Journal of the Bombay Natural
History Society 15: 727.
Fuller,
N. (1958). Additions to the birds of the Palni Hills
(south India). Journal of the Bombay Natural History Society 55(1):
159–160.
Islam,
M.Z. & A.R. Rahmani (2004). Important Bird Areas
in India: Priority Sites for Conservation. Indian Bird Conservation
Network: Bombay Natural History Society and BirdLife International (UK),
xxvii+1133pp.
Jayapal,
R., Q. Qureshi & R. Chellam (2007). Developing
a spatial conservation protocol for Central Indian Highlands through a
biogeographical analysis of birds and existing Protected Area network: A
Geographical Information Systems approach. Research Report, Wildlife Institute
of India, Dehradun, 200pp.
Jayson,
E.A. (1994). Synecology and behavioural studies on the
forest birds of Kerala. PhD Thesis, University of Calicut, Calicut, 314pp.
Johnsingh,
A.J.T. & J. Joshua (1994). Avifauna in three
vegetation types on Mundanthurai Plateau, south India. Journal of
Tropical Ecology 10: 323–335.
Kattan,
G.H. & P. Franco (2004). Bird diversity along
elevational gradients in the Andes of Colombia: area and mass effects. Global
Ecology and Biogeography 13: 451–458.
Khan,
J.A., D.N. Khan & A. Ahmed (1993).Preliminary investigations of bird community structure at Aligarh, India. Tropical
Ecology 34: 217–225.
Kremen,
C. (1992). Assessing the indicator properties of the
species assemblages for natural areas monitoring. Ecological
Applications 2: 203–217.
Lee,
P.-F., T.-S. Ding, F.-H. Hsu & S. Geng (2004).Breeding bird species richness in Taiwan: distribution on gradients of
elevation, primary productivity and urbanization. Journal of Biogeography31: 307–314.
MacArthur,
R.H. (1972). Geographical Ecology: Patterns in the
Distribution of Species. Harper and Row, New York, 269pp.
Narayana,
T.V. (1979). Birding in and around Kodaikanal. (ca.
May 15–June 15). Newsletter for Birdwatchers 19(10): 2–5.
Navarro,
A. (1955). Some new bird records in the Palni Hills,
south India. Journal of the Bombay Natural History Society 53(1):
133–134.
Nichols,
E.G. (1937). The Kodaikanal birds and how to name
them. Journal of the Bombay Natural History Society 39(4):
812–830.
Pascal,
J.P. (1988). Wet Evergreen Forests of the Western
Ghats of India: Ecology, Structure, Floristic Composition and Succession. Institut
Français de Pondichéry, India, 365pp.
Pramod,
P., N.V. Joshi, U. Ghate & M. Gadgil (1997). On
the hospitality of Western Ghats habitats for bird communities. Current
Science 73(2): 122–127.
Prater, S.H. (1971). The
Book of Indian Animals. Bombay Natural History Society, Oxford University
Press, Bombay.
Rajmohana,
K. & C. Radhakrishnan (2008). Western Ghats- A Hotspot
of Biological Wealth. Technical Report, Western Ghats Field Research Station,
Zoological Survey of India, Kozhikode, Kerala, 32pp.
Rahmani,
A.R. (2008). Flight to extinction. Spectrum, The
Tribune. Retrieved June 8, 2008, from
http://www.tribuneindia.com/2008/20080608/spectrum/Main1.htm.
Raman,
T.R.S., N.V. Joshi & R. Sukumar (2005). Tropical
rainforest bird community structure in relation to altitude, tree species
composition, and null models in the Western Ghats, India. Centre for Ecological
Sciences, Indian Institute of Science, 34pp.
Ramesh, T., N. Sridharan & R. Kalle (2011). Birds of Kuno Wildlife Sanctuary, Central
India. Zoo’s Print 26(12): 25–29.
Recher,
H.F. & W.E. Davis (2002). Foraging profile of a
Salmon Gum woodland avifauna in Western Australia. Journal of Royal Society
of Western Australia 85: 103–111.
Robin,
V.V. & R. Sukumar (2002). Status and habitat
preference of White-bellied Shortwing Brachypteryx major in the Western
Ghats (Kerala and Tamil Nadu), India. Bird Conservation International12: 335–351.
Shahabuddin,
G. (1997). Preliminary observations on the role of
coffee plantations as avifaunal refuges in the Palni Hills of the Western
Ghats. Journal of the Bombay Natural History Society 94(1): 10–21.
Shafiq,
T., S. Javed & J.A. Khan (1997). Bird
community structure of middle altitude oak forest in Kumaon Himalayas, India: a
preliminary investigation. International Journal of Ecology and
Environmental Sciences 23: 389–400.
Somasundaram,
S. & L. Vijayan (2008). Foraging behaviour and guild
structure of birds in the montane wet temperate forest of the Palni Hills,
south India. Podoces 3(1/2): 79–91.
Steele,
A. (1990). Birds of Petuparai, Kodaikanal. Newsletter
for Birdwatchers 30 (7–8): 9.
Surendran,
K.K. (1973). The crow in Kodaikanal, Palni Hills.
India. Newsletter for Birdwatchers 13(8): 10.
Terry,
H.A. (1887). A few additional notes on birds of the
Pulney Hills. Stray Feathers 10: 467–480.
Vijayan
L. & V. Gokula (2006). Human Impact on the Bird Communities in
the Western Ghats. In: Proceeding of the Chinese Acad. Sciences. Proceeding of
the 23rd International Ornithological Congress, Beijing 2002.
Symposium paper. Acta Zoologica Sinica 52: 692–696.