First detailed survey of
waterbirds in Tirunelveli and Tuticorin districts, Tamil Nadu, India
K. Abhisheka 1, J.
Patrick David 2, M.B. Prashanth 3, K.S. Seshadri 4& T. Ganesh 5
1,2,3,4,5 Ashoka Trust for Research in
Ecology and the Environment, Royal Enclave, Srirampura, Jakkur post, Bengaluru,
Karnataka 560064, India
Present address: 2 Careearth
Trust, 8/15, 2nd Main Road, Thillaiganga Nagar, Chennai, Tamil Nadu 600061,
India
Present address: 4 Department
of Biological Sciences, National University of Singapore, 14 Science Drive 4,
Singapore 117543
1 abhishekagopal@gmail.com
(corresponding author), 2 patdavid28@gmail.com, 3 prashanth.mb@atree.org,
4 seshadri.ali@gmail.com, 5 tganesh@atree.org
Abstract: The semi-arid districts of
Tirunelveli and Tuticorin in the southern Indian state of Tamil Nadu consist of
numerous wetlands in the form of irrigation tanks, interconnected by an ancient
network of canals, and fed by the rivers originating from the Western
Ghats. While these irrigation tanks
have socio-economic and cultural significance, very little is known of their
ecological importance. These tanks
have the potential to harbor good populations of resident and wintering
waterbirds but no studies have been done to confirm this. A survey was carried out in 230
irrigation tanks of various sizes in the two districts from November 2008 to
January 2011. A total of 83
waterbird species were recorded. Indian Pond Heron Ardeola grayii occurred in most of the surveyed
tanks. Large concentrations of wintering waterfowl such as Eurasian Wigeon Anaspenelope, Northern Pintail Anas acuta,
Garganey Anas querquedula were recorded in tanks closer to the
coast. Based on our survey, six
sites with large waterbird concentrations have been identified, one of which is
Vagaikulam, an active heronry currently under threat from tree felling. These sites along with associated
wetlands are important for the long term conservation
of waterbirds in the region.
Keywords: Heronry, irrigation tanks,
long term monitoring, waterfowl.
doi: http://dx.doi.org/10.11609/JoTT.o3125.4641-52 | ZooBank: urn:lsid:zoobank.org:pub:5ECC9346-22C9-42BF-A4A4-99B859FDB906
Editor: K.S. Gopi Sundar, International Crane Foundation, Baraboo, USA. Date
of publication: 26 August 2013 (online & print)
Manuscript
details: Ms # o3125 | Received 16 March 2012 | Final received 07
July 2013 | Finally accepted 07 August 2013
Citation: Abhisheka, K., J.P. David, M.B. Prashanth, K.S. Seshadri & T.
Ganesh (2013). First detailed survey of waterbirds in Tirunelveli and Tuticorin
districts, Tamil Nadu, India. Journal of Threatened Taxa 5(12): 4641–4652; http://dx.doi.org/10.11609/JoTT.o3125.4641-52
Copyright: © Abhisheka et al. 2013. Creative Commons Attribution 3.0
Unported License. JoTT allows unrestricted use of this article in any
medium, reproduction and distribution by providing adequate credit to the
authors and the source of publication.
Funding: This study was funded by the Ecosystem Grant
Programme of the International Union
for Conservation of Nature,
Netherlands.
Competing
Interest: Authors declare no competing interest.
Acknowledgements:We thank Dr. Aravind N A, Dr. Chetana H C and Mr. Samuel
Jacob for their valuable inputs; Mr. M. Mathivanan and other staff of the
Agasthyamalai Community based Conservation Centre, at Manimutharu for help and
logistic support. We are grateful to Ms. Deepa Ruth Varkey, Mr. Saleem Hameed
and all other volunteers and vehicle drivers who lent invaluable support during
the field work.
Author Contribution: TG designed the study. KA, JPD, MBP, KSS and TG collected the
data, analysed and wrote the manuscript. MBP designed the map.
Author Details: K. Abhisheka, Ecologist,
trained artist and also an urban wildlife rehabilitator. She uses her
experience in field ecology and the medium of art to reach out to people on
conservation related issues. She is currently a freelancer.
J. Patrick David, Ecologist, currently working as project co-ordinator with Care
Earth Trust, Chennai. His responsibility is to survey for birds in the Eastern
Ghats of Tamil Nadu and identify birding hotspots.
M.B. Prashanth, interested in avian diversities in wetlands and is currently
working on the mapping of wetlands and their habitat characteristics in
relation to diversity and abundance of waterbirds. Has been involved in the
co-ordination, surveying and compiling reports of the mid-winter waterbird
census in the Tamiraparni river basin. Currently with ATREE.
K.S. Seshadri, Ecologist, primarily interested in understanding how human
actions alter the ecosystems. As a Graduate student, he is studying the ecology
and behavior of red-listed amphibians in the Western Ghats. Currently pursuing
PhD at Department of Biological Sciences, National University of Singapore.
T. Ganesh, Ecologist, for over three decades, he has worked and
advised students on various ecological aspects primarily focussing on
plant-animal interaction; bird and primate ecology; ecological restoration and
long term monitoring of forests. He has also authored a bilingual multi taxa
field guide. He is currently a senior fellow at ATREE.
For figures, tables -- click here
Introduction
Wetlands, both natural and
artificial, support a high diversity of resident and migrant waterbirds
(Amezaga et al. 2002). Though there
are numerous such habitats for birds across India, very few have been
systematically surveyed to understand their importance for birds. This is especially true for many small
ones that are in an agricultural landscape often fed by man-made irrigation
networks and collectively supporting large populations of waterbirds. As part of conservation efforts, isolated
wetlands or heronries in the agricultural areas get listed as important bird
areas (IBA). Though such efforts
are important, they provide inadequate coverage, and are of limited value
unless the surrounding habitat matrix such as swamps, canals, wet agricultural
areas - which effectively sustain a good population of birds are included in
the conservation plans (Elphick et al. 2010; Sundar 2011). It, therefore
becomes imperative that a landscape approach is used to establish the
importance of wetlands for waterbirds.
The districts of Tirunelveli
and Tuticorin in the semi-arid landscape of southern Tamil Nadu have many
man-made, small- to large-sized, irrigation tanks (henceforth called
tanks). These inland tanks were
built a few centuries ago and are interconnected by canals that bring water from
the rivers originating in the Western Ghats (Vaidyanathan 2001). These rivers and associated tanks
support a rich social and cultural heritage and economically support
agriculture that is the main source of livelihood for the people in these
districts.
The tanks in these two
districts are known to support large populations of the Near Threatened
Spot-billed Pelican Pelecanus philippensis, and Painted Stork Mycteria
leucocephala (Kannan & Manakandan 2005; Subramanya 2005). They also provide suitable habitat for
the Greater Flamingo Phoenicopterus roseus (Sathan & Pandi 2009) and
sustain a variety of migrant water birds during the winter. Not surprisingly, the area has also been
known to sustain heronries like Koonthankulam, Gangaikondan, Moondradaippu,
Tirupudaimarathur, Vijayanarayanam, Karungulam and Ariyakulam (Krishnan 1978;
Nagulu & Rao 1983; Subramanya 1996). However, past reports were based on small-scale surveys and are outdated as some of the aforementioned heronries do not
exist today.
Though there are studies on
birds in the two districts, most have been restricted to forest birds in the
neighboring Kalakad-Mundanthurai Tiger Reserve (KMTR) (Johnsingh & Joshua
1989, 1994; Johnsingh 2001; Raman & Sukumar 2002), whereas in the semi-arid
plains, focus has been on Koonthankulam and other heronries (Rhenius 1907; Webb-Peploe 1945; Wilkinson 1961; Subramanya 2005). While Koonthankulam is notified as an
IBA, scant attention is given to the other tanks in this network
which potentially harbor a high diversity of resident and migratory
waterbirds. There are over 3000
tanks here and some of them are large (over 1700 acres). There is a need to identify tanks
important for resident and migrant waterbirds, and prioritize them for
conservation. Moreover, the tanks
and agricultural fields in these two districts along with the neighbouring
Kanyakumari District are located towards the southern tip of the Indian
peninsula and therefore provide critical wintering habitats for many migrant
species. Several of these tanks are, however, threatened by various
anthropogenic factors (Abhisheka et al. 2012). In this context, robust baseline information
on waterbird diversity and populations can provide a starting point for future
monitoring, conservation planning and developing pertinent management
interventions.
In this paper we provide the
results of a survey of 230 tanks to document the diversity and abundance of
waterbirds in Tirunelveli and Tuticorin districts of Tamil Nadu. We identify key sites that harbor large
populations of resident and migrant waterbirds that will be useful for
waterbird conservation.
Study
area and Methods
Located in the southern most
part of India, the two districts, Tirunelveli (8008’–9023’N
& 77009’–77054’E) and Tuticorin (8049’N
& 7808’E) are encompassed by the Western Ghats on the west and
the Bay of Bengal on the east. This
region is known as the rice bowl of southern Tamil Nadu, made possible by the
many rivers that originate in the Agasthyamalai Hills, and also as a biosphere
reserve and a proposed world heritage site (Rehman & Shrivastava 2012). The numerous tanks (~3000) that lie in
the semi arid plains of these two districts are fed by seven perennial rivers
viz., Thamiraparani and its tributaries: Manimuthar, Pachaiyar, Kodumudiyar,
Gadananathi, Ramanathi and Nambiar which form the lifeline of about five
million people living in the immediate landscape (Gazetteer 2002). The Thamiraparani is a major river,
which plays a vital role by providing water for irrigation and sustaining the
people living in its basin. The
river originates from the catchments of the Periya Pothigai hills in the
Agasthyamalai region of the Western Ghats and traverses through the two
districts before joining the Gulf of Mannar in the Bay of Bengal at Punnaikayal.
The river-canal-tank network
in the semiarid landscape sustains extensive paddy agriculture in the
region. The old trees and
plantations in the region support heronries while the Borassus flabelliferpalm traditionally planted around the tanks offers roosting sites for numerous
resident birds. A survey of 230
small to large tanks (10–1705 acres) based on size and logistics was
carried out in three phases in the districts of Tirunelveli and Tuticorin from
November 2008 to January 2011 (Appendix 1). A very large proportion (>50%) of
small tanks close to the forests were surveyed during this period. Surveys were carried out between
September to February for two reasons: one, it included the wintering period
for migrant waterfowl and second, the September to October period is a dry
period with very few tanks having water. This allowed us to identify critical tanks where waterbirds could be
found during water shortage in the larger landscape. Though this is biased against migratory
birds these water bodies can be critical for resident species
which experience seasonal water shortages on a regular basis. Indian Remote Sensing Satellite, Google
Earth images, maps from the Survey of India and information from Public Works
Department, Government of Tamil Nadu were used to locate wetlands for the
survey. These sources of
information were also used to determine the extent of each tank in acres.
During the first phase, 177
tanks were surveyed along the foothills of KMTR spread over a distance of 65km
from November 2008 to September 2010. Nearly all tanks close to the rivers Gadananathi, Thamiraparani,
Manimuthar, Pachaiyar and Nambiar were surveyed. In the second phase, all the tanks on
the banks of the Thamiraparani river in both districts
were surveyed (n=22) in the month of September 2010. In the third phase, a mid-winter
waterfowl census was conducted across the two districts in Jan 2011 (n=42). Eleven tanks surveyed in the earlier two
phases were part of the 42 tanks. Only large tanks were chosen for the mid-winter survey as many
volunteers were available for the survey and it could be done in 2–3 days
(Fig. 1). All large tanks in the
dry areas of the districts away from the river basin were also surveyed. In
total, 230 individual tanks were covered during the two phases and the
mid-winter waterfowl census.
In each of the tanks, the
number of bird species and the number of individuals were recorded. The total number of birds was enumerated
by walking along the periphery of the tanks in the mornings from
06:30–09:30 hr or in the evenings from 16:00–18:00 hr as this time
period was found to be most appropriate during pilot surveys. Large tanks were divided into blocks to
simplify counting and sometimes were surveyed beyond 09:30 hr due to their
size. Waterbirds were counted from
a few vantage points, as gaining access to all sides of the tank was difficult
in a few cases. A minimum of two
members for small to medium tanks and four members, split into two groups, for
large tanks, counted the birds. All
members of the team were experienced bird watchers and familiar with water bird
counting. The
mid-winter waterfowl census was carried out by over 30 people split into two or
four groups, with each group having at least one experienced birdwatcher. Often, in large wetlands complete counts
were biased by the presence of vegetation and large distance from bird to the
shore and may have led to underestimates of counts but not so in smaller
wetlands. We also recognize that abundance estimates can be biased by observer, year, day of count,
potential double counting, and other factors, but were unable to account
for these in our study.
All surveys were carried out
using binoculars (8X40, 10X50) or using spotting scopes (10X100). Geographic coordinates (latitude and
longitude) were obtained at one arbitrary point for each tank using a Garmin®
hand-held global positioning system.
Tanks critical for water bird
conservation was decided based on the presence of heronry, high species
richness, greater abundance of waterbirds, habitat diversity present in the
wetland, and availability of water during the dry seasons spanning from March to
October. Local villagers around the
tanks were consulted about the tank’s history, source of water and the
availability of water in it. Grouping of birds, classification, common and latinnames were based on international ornithological committee (IOC) World Bird
Names (Gill & Donsker 2012). Species’ global status was ascertained using the IUCN classification
(IUCN 2010).
Results
and Discussion
A total of 83 species of
waterbirds were recorded in the 230 tanks surveyed (Appendix 2). Of the 83 species about 41% were
migrants, 26% local migrants and 33% residents. More than 13,164 individuals and 69
species were recorded during the phase one survey of 177 small tanks in the
foothills of KMTR. In phase two
20,406 individuals of 58 species were recorded in 22 tanks and finally 32,379
birds of 71 species were recorded in 42 tanks during the mid winter waterbird
census. These variations were
mostly due to the size of tanks, since tanks surveyed in phase one were smaller
than in other phases.
Indian Pond Heron Ardeola
grayii was the most common species and occurred in 76% of the 230 tanks
surveyed, followed by Little Egret Egretta garzetta (75%) and Little
Cormorant Phalocrocorax niger (71%). A few species were recorded in only one
tank, and some examples of these are Black-capped Kingfisher Halcyon pileata,
Common Tern Sterna hirundo, Great Thick-Knee Esacus recurvirostri,
Lesser Sand Plover Charadrius mongolus, Little Stint Calidris minuta,Oriental Pratincole Glareola maldivarum, Ruff Philomachus pugnax,
Small Pratincole Glareola lactea, Watercock Gallicrex cinereaand Whimbrel Numenius phaeopus. Four bird species in the Near Threatened
category; Black-headed Ibis Threskiornis melanocephalus, Oriental DarterAnhinga melanogaster, Painted Stork and Spot-billed Pelican were
recorded in large numbers in these tanks. Some species like the Black-capped
Kingfisher was restricted to the foothills while Ruff, Whimbrel, Eurasian
Wigeon Anas penelope and Lesser Sand Plover
were seen more often in tanks closer to the coast.
The Common Pochard Aythya
ferina, Eurasian Wigeon, Great Thick-Knee, Pied Avocet Recurvirostra
avosetta, Ruff, Whimbrel and Watercock were sighted for the first time
during the survey. Though all of
these species are expected to occur in the region (Grimmett et al. 1999), there
have been no prior reports from the focal districts.
Among the tanks surveyed, six
were prioritized for conservation attention (Table 1). Three tanks were chosen on the basis of
having waterbird abundance greater than 1% population threshold as per Ramsar
criteria (Table 2). The other three
were chosen based on the high abundance and species richness of birds. While we highlight only six tanks, all
the tanks have a great potential to support large waterbird congregations, and
they are also existing and potential nesting/roosting sites. The six tanks are represented in Fig. 1
along with all the large tanks.
Vagaikulam (81 acres)
situated at Nanalkulam near Alwarkurchi in Tirunelveli district was found to
support 45 species. It has no other heronries in a radius of 65 km and is one
of the largest heronries in the district of Tirunelveli after the Koonthankulam
bird sanctuary. The tank comprises of semi submerged Acacia nilotica trees
and is an important nesting and roosting site for several non-migratory species
of birds like Black-crowned Night Heron Nycticorax nycticorax,
Black-headed Ibis, Little Cormorant, Indian Cormorant Phalacrocorax
fuscicollis, Great Cormorant Phalacrocorax carbo, Little Egret, Indian
Pond Heron, Little Grebe Tachybaptus ruficollis, Common Moorhen Gallinula
chloropus, Pheasant-tailed Jacana Hydrophasianus chirurgus and
Bronze-winged Jacana Metopidius indicus. The tank also supports roosting
populations of Glossy Ibis Plegadis falcinellus, Spot-billed Pelican and
ducks like Cotton Pygmy-Goose Nettapus coromandelianus, Garganey Anas
querquedula, Northern Pintail Anas acuta, and Lesser
Whistling-Duck Dendrocygna javanica. The water in the tank is seasonal
and the heronry is active from November to March. The heronry is under threat
from the felling of Acacia nilotica trees planted by the forest
department.
Pirancheri Periyakulam (94
acres) situated on the Tirunelveli-Ambasamudram main road supported 45 species
during this survey. The floating vegetation in the tank along with grass
and reeds makes this a suitable habitat for dabbling as well as wading birds.
The vegetation provides nesting habitat for Moorhens, Jacanas and Herons. Water
from Thamiraparani feeds this tank and it is perennial. Weed infestation and
dumping of garbage is posing significant threat to this tank. Expansion of a
road in future is another possible threat to the tank.
Vattakulam (125 acres)
situated on the Cheranmadevi–Nagercoil Road is a large tank close to
Tirukurangudi Village at the southern end of Kalakad Mundanthurai Tiger
Reserve. During the survey 33
species were recorded. Pelicans, storks, and egrets congregate here in large
numbers to feed on the fish in the shallow water when the tank starts to dry
out. The tank shore
line is used by several small waders like the Common Sandpiper Actitis
hypoleucos, Black-winged Stilt Himantopus himantopus, Little Ringed
Plover Charadrius dubius and Marsh Sandpiper Tringa stagnatilis. The tank is seasonal and fed by the Nambiar
River. We did not document any
major threat to the tank during our survey.
Kadamba Kulam was the
largest tank surveyed (1705 acres) and is situated close to the town of
Sirivaikuntam in Tuticorin District. It is a mini reservoir which feeds about 14
smaller tanks. The highest number
of birds was recorded here (21,354) and about 44 species. Very large concentrations of wintering
waterbirds, especially waterfowl are found here from December through February,
especially large numbers of ducks such as Eurasian Wigeon, Northern Pintail,
and Northern Shoveler Anas clypeata. During the dry season when all tanks fed
by the Thamiraparani river go dry, birds congregate at
this tank in huge numbers. At
present this tank does not experience any major threat.
Arumugamangalam tank (786
acres) is situated on the Sirivaikuntam–Eral Road in
Tuticorin District and supported about 26 species. This is also an important tank for
migratory ducks. Large
concentrations of Eurasian Wigeons were seen here. The Borassus
flabellifer palm trees planted around the tank are used for nesting by a
small population of Spot-billed Pelicans. Birds in this tank are
threatened by poaching and more recently, the water was let out to
Tuticorin City for nonagricultural purposes during the dry season, which was
not done earlier.
Vijayanarayanan Periyakulam is one of the biggest tanks (819 acres) in Tirunelveli District. The second highest numbers of birds were
recorded here (6,227) and about 38 species. This tank is situated close to Bird
Sanctuary and hundreds of Greater Flamingoes frequent this tank occasionally. Large numbers of Bar-headed Goose were
seen here and along with Koonthakulam, Nanguneri Periakulam close to Nanguneri
Town, and Ponnakudi Kulam on the highway provide important wintering habitat
for the geese and Common Pochards and is therefore an important tank for them
in the arid landscape of south Tirunelveli District.
Along with the irrigation
network, the vast expanses of salt-pans near Tuticorin
and the estuarine regions of Thamiraparani are important bird habitats that
need further scrutiny. The salt-pans also attract flamingoes and several species of
shorebirds. In September 2010, over
a few thousand waders were spotted circling in the sky in the Sagupuram area which is close to the coast and a pair of Greater Flamingoeswas spotted in the salt pan in the same area in January 2011.
Conservation
implications
We list only six tanks as
high priority sites because of the potential of these tanks in supporting high
waterbird diversity and abundance. A total of 40,792 individuals and 67 species were recorded from these
six tanks. Some of the birds seen
in heronries like Vagaikulam fly off to several smaller tanks along the
foothills of KMTR. Birds like
the Bar-headed Goose move across a network of large tanks around
Vijayanarayanam Periyakulam. There
is a need to monitor these and other tanks in the region on a regular basis to
identify more important sites and understand the ecological importance of the
tanks better. Such monitoring has
to involve a more landscape approach that would help understand the dynamics of
bird movement especially related to water shortages and rainfall variability
that would be relevant in the context of climate change. We could not assess how detectability
due to various factors affected bird counts during our survey. Future studies designed to incorporate
more robust counting techniques can assist in providing improved waterbird
estimates.
Threats like poaching, over
fishing, land use change, drying out tanks for agriculture by excessive pumping
of water using motors which was not done earlier, etc could pose threats to
waterbirds in the small tanks harboring low bird abundances. The tanks need protection since they are getting choked by invasive species like Ipomea and
water hyacinth, polluted by small industrial units, tank beds are
encroached on for agricultural and nonagricultural purposes. For sustaining waterbirds in the arid
landscape we need to conserve such water bodies in conjunction with a network
of large and/or small tanks in the near vicinity.
Our survey showed that very
few tanks had trees within which serve as islands when the tank is inundated
and can provide safe nesting and roosting sites. The few tanks which
had trees consisted of Acacia nilotica planted by the Forest
Department or Panchayat earmarked for harvesting under the social forestry
scheme. These trees, used by birds
for nesting and roosting are eventually harvested making the tank devoid of
nesting habitats as in the case of Vagaikulam. It is imperative that forestry practices
are carried out incorporating the breeding and roosting requirements of waterbirds
in the area. The foreshore
plantations by the forest department, that are inundated when the tank has
water, have not been taken up in tanks which are either known for their
heronries or have a high potential for being so. It is, therefore, necessary to revive
such planting programs within the tank and its periphery with more diversity of
trees and to ensure that not all trees are harvested. In smaller tanks, such plantations
should be limited to a portion of the tank so that the rest of the tank is left
open to be used by dabbling and diving waterbirds, and also for human
activities like fishing, grazing, removal of silt for agricultural purposes
during the dry season, and for domestic purposes.
Though most tanks in the
areas do not require any management for bird conservation, tanks that are
potential habitat (heronry) of birds are at risk. The heronry at Moondraiadippu near
Tirunelveli was lost to excessive poaching, tree
felling, road widening and the forest department could not intervene in time. On the other hand, the heronry at
Vagaikulam was protected from contract felling by initiatives of the local
communities and an NGO (Abhisheka et al. 2012). There are also some well
known initiatives from local communities to protect and conserve birds in
the wetlands of the region. The
Koonthankulam Bird Sanctuary in Tirunelveli which is recently
being protected by the State Forest Department was a community protected
area (Rhenius 1907; Wilkinson 1961). Whereas in the neighboring district of
Kanyakumari the forest department itself is taking initiatives to make select
wetlands as conservation reserves (Kumar 2012). We need to think of various innovative
measures that prevent loss of heronry and wetlands to rapid urbanization
happening in the region along with improved monitoring and documentation.
References
Abhisheka, K., K.S. Seshadri,
M.B. Prashanth & T. Ganesh (2012). The Agasthyamalai landscape: Land of mountains,
wetlands and biodiversity. Sanctuary Asia XXXII(4): 44–47
Amezaga, J.M., L. Santamaría
& A.J. Green (2002). Biotic wetland connectivity - supporting a new
approach for wetland policy. Acta Oecologica 23(3):
213–222; http://dx.doi.org/10.1016/S1146-609X(02)01152-9
Baskaran, T.S. (2006). Visitors
at Koondhankulam. The Hindu.
<http://www.hindu.com/mag/2006/12/17/stories/2006121700060200.htm>.
Downloaded on 19 Aug 2012.
BirdLife International (2001). Threatened Birds of Asia: The BirdLife International Red Data Book.
BirdLife International, Cambridge, UK,
Elphick. C.S.,
P. Baicich, K.C. Parsons, M. Fasola & L. Mugica (2010). The Future
for Research on Waterbirds in Rice Fields. Waterbirds 33 (Special
Publication 1): 231–243; http://dx.doi.org/10.1675/063.033.s117
Gill, F.
& D. Donsker (eds). (2012). IOC
World Bird Names (v 3.1). Available at
http://www.worldbirdnames.org [Accessed 16th August 2012].
Grimmett, R., C. Inskipp
& T. Inskipp (1999). Pocket Guide to the Birds of Indian Subcontinent. Oxford
University Press, New Delhi, 384pp.
Islam,
M.Z. & A.R. Rahmani (2004). Important Bird Areas in India. Priority Sites for Conservation. Network: Bombay
Natural History Society and Bird Life International (UK), xviii+1133pp.
Islam,
M.Z. & A.R. Rahmani (2008). Potential and Existing Ramsar
Sites in India. Network:
Bombay Natural History Society, Bird Life International and Royal Society for
the protection of Birds. Oxford University Press, New Delhi,
592pp.
IUCN
(2010). IUCN Red List of Threatened Species. Version 2010.4.
<www.iucnredlist.org>. Downloaded on
03 August 2011.
Johnsingh, A.J.T. (2001). The Kalakad-Mundanthurai
Tiger Reserve: A global heritage of biological diversity. Current
Science 80: 378–388.
Johnsingh,
A.J.T. & J. Joshua (1994). Avifauna in three vegetation types on
Mundanthurai Plateau, south India. Journal of Tropical Ecology 10(3):
323–335; http://dx.doi.org/10.1017/S0266467400007999
Johnsingh,
A.J.T. & J. Joshua (1989). The threatened gallery forest of the River
Tamirabharani, Mundanthurai Wildlife Sanctuary, south India. Biological Conservation 47: 273–280.
Kannan,
V. & R. Manakadan (2005). The status and distribution of Spot-billed Pelican Pelecanus
philippensis in southern India, FORKTAIL 21: 9–14
Krishnan,
M. (1978). The availability of nesting materials and nesting sites as vital
factors in the gregarious breeding of Indian water-birds.
Journal of the Bombay Natural History Society 75(supplement):
1143–1152.
Kumar, P.S.S. (2012). Hearts aflutter as Kumari
gets wetland bird reserve.
http://www.thehindu.com/todays-paper/tp-features/tp-editorialfeatures/article3671341.ece.
Downloaded on 23 July 2012.
Li, Z.W.D., A. Bloem, S.
Delany, G. Martakis & J.O. Quintero (2009). Status of Waterbirds in
Asia - Results of the Asian Waterbird Census: 1987–2007. Wetlands
International, Kuala Lumpur, Malaysia
Nagulu, V. & J.V.R. Rao (1983). Survey of south Indian pelicanries. Journal
of the Bombay Natural History Society 80 (1): 141–143.
Raju, K.V., G.K. Karanth,
M.J. Bhende, D. Rajasekhar & K.G. Gayathridevi (2003). Rejuvenating Tanks - A
Socio-ecological approach. Collaborative initiative of
Institute for Social and Economic Change and Books for Change, Bangalore,
331pp.
Raman, T.R.S. & R.
Sukumar (2002). Responses of tropical rainforest birds to abandoned plantations,
edges and logged forest in the Western Ghats, India. Animal Conservation 5(3):
201–216; http://dx.doi.org/10.1017/S1367943002002251
Rehman,
S, & K.S. Shrivastava (2012). Western Ghats get World Heritage Site tag. <http://www.downtoearth.org.in/content/western-ghats-get-world-heritage-site-tag>.
Downloaded on 7th July 2012.
Rhenius, C.E. (1907). Pelicans
breeding in India. Journal of the Bombay Natural
History Society 17(3): 806–807.
Sathan,
C. & B. Pandi (2009). Diary on the Nesting Behaviour of Indian
Birds. Sugeeth Publishers, Coimbatore,
Tamil Nadu, 223pp.
Sreenivasan,
R. & P.A. Kumar (2004). Vision for Village Tanks of Tamil Nadu. DHAN Foundation, Madurai, Tamil Nadu, 34pp.
Subramanya, S. (1996). Distribution, Status and Conservation of Indian Heronries Journal
of the Bombay Natural History Society 93(3):
459–486.
Subramanya, S. (2005). Heronries of Tamil Nadu. Indian Birds 1(6):
126–140.
Sundar, K.S.G. (2011). Agricultural
intensification, rainfall patterns, and large waterbird breeding success in the
extensively cultivated landscape of Uttar Pradesh, India. Biological
Conservation 144(12): 3055–3063; http://dx.doi.org/10.1016/j.biocon.2011.09.012
Vaidyanathan, A. (2001). Tanks
of South India. Centre for Science and Environment, New Delhi,
178pp.
Velmani, K.S.K. (2002). Tirunelveli
District Gazetteer, Chennai.
Webb-Peploe, C.G. (1945). Notes on a few birds from south of the Tinnevelly
district. Journal of the Bombay Natural History
Society 45: 425–426.
Wetlands
International (2012). Waterbird Population Estimates, Fifth Edition.Summary Report. Wetlands International, Wageningen, The Netherlands
Wilkinson, M.E. (1961). Pelicanry
at Kundakulam, Tirunelveli District. Journal of the
Bombay Natural History Society 58: 514–515.
Websoureces:
Bird Sanctuaries in Tamil Nadu: Koonthankulam Bird Sanctuary.
<http://www.forests.tn.nic.in/WildBiodiversity/bs_kkbs.html>. Downloaded
on 19 Aug 2012
Bird biodiversity: Kalakad Mundanthurai Tiger
Reserve. <http://www.forests.tn.nic.in/WildBiodiversity/tr_kmtr.html>.
Downloaded on 19 Aug 2012
Tirunelveli District,
Official website. < http://www.nellai.tn.nic.in>. Downloaded on 15 July
2011.
Thoothukudi District: Official website. <
http://thoothukudi.tn.nic.in>. Downloaded on 15 July 2011.