Journal of Threatened
Taxa | www.threatenedtaxa.org | 26 July 2026 | 18(7): 29226–29237
ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print)
https://doi.org/10.11609/jott.10212.18.7.29226-29237
#10212 | Received 15 October 2025 | Final received 10 February 2026|
Finally accepted 27 June 2026
Diversity and habitat
associations of avifauna in the Poovar Estuary, Kerala,
India
B.S. Bipitha 1 , V. Reshmi 2 , H. Maitreyi 3 & H. Byju 4
1,2 Department of Zoology, BJM
Government College, Chavara, Kollam, Kerala 691583,
India.
3,4 Centre of Advanced Study in
Marine Biology, Annamalai University, Parangipettai,
Tamil Nadu 608502, India.
1 bsbipitha@gmail.com, 2 reshmidileeb@gmail.com,
3 maithgd@gmail.com, 4 byjuhi@gmail.com (corresponding
author)
Editor: Anonymity requested. Date
of publication: 26 July 2026 (online & print)
Citation: Bipitha, B.S., V. Reshmi, H. Maitreyi
& H. Byju (2026). Diversity and
habitat associations of avifauna in the Poovar
Estuary, Kerala, India. Journal of
Threatened Taxa 18(7):
29226–29237. https://doi.org/10.11609/jott.10212.18.7.29226-29237
Copyright: © Bipitha et al. 2026. Creative Commons Attribution 4.0
International License. JoTT allows unrestricted use,
reproduction, and distribution of this article in any medium by providing
adequate credit to the author(s) and the source of publication.
Funding: None.
Competing interests: The authors declare no competing interests.
Author details: B.S. Bipitha is an MSc Zoology student of BJM College, Chavara, Kerala. V. Reshmi, associate professor in Zoology, BJM College, Chavara, Kerala, with a decade of experience in research. H. Maitreyi, PhD scholar of Centre of Advanced Study in Annamalai University, working on waterbirds in the Gulf of Mannar region, Tamil Nadu. H. Byju, senior researcher of Centre for Advanced Study, Annamalai University, with decades of experience in wetlands and waterbirds on Peninsular India.
Author contribution: BSB—data collection, first draft writing; VR—research planning, data curation, writing and supervision; HM—data curation, analysis and writing; HB—supervision, planning, writing and editing.
Acknowledgements: We thank the Department of Zoology and the college authorities for facilitating this work. We are also grateful to a few friends who accompanied us on the field studies.
Abstract: This study assessed bird
diversity in Poovar, a coastal wetland complex in
Thiruvananthapuram district, Kerala, India, from August 2024 to July 2025. 88
bird species from 17 orders and 37 families were documented, encompassing both
resident and migratory populations. According to the IUCN Red List, all species
were categorized as ‘Least Concern’ except for the River Tern Sterna aurantia and Oriental Darter Anhinga melanogaster,
listed as ‘Vulnerable’ and ‘Near Threatened’, respectively. Based on migratory
status, 56 species were residents and 32 were winter visitors, highlighting the
role of Poovar as a significant refuge for migratory waterbirds along the southwest coast of India. Feeding
guild analysis showed that 34% of species were insectivorous, followed by
carnivores and piscivores, reflecting the functional diversity of the
community. Habitat association indicated waterbirds
utilized varied habitats, showing overlap in habitat-specific assemblages such
as backwater, mangroves, and beaches, emphasizing the influence of habitat
heterogeneity on avian distribution. Urban areas showed a distinctive species
composition having little overlap with farmland assemblages. The habitat mosaic
of Poovar supports a diverse and dynamic avifaunal
assemblage. Habitat association analysis indicated that waterbirds
utilized a variety of habitats.
Keywords: Avifaunal list, biodiversity,
backwater, beach, estuary, habitats, Kerala, migratory birds, species
assemblage, urban birds.
Introduction
Tropical coastal ecosystems are
among the most productive and biologically rich environments globally,
supporting a high diversity of avifauna that fulfil critical ecological roles (Rashiba et al. 2022). Birds make significant contributions
to ecosystem functioning through processes such as pollination, seed dispersal,
regulation of invertebrate and rodent populations, scavenging, and nutrient
cycling (Şekercioğlu 2006; Archana et al. 2024). The
composition and structure of avian communities in these dynamic landscapes are
strongly influenced by habitat heterogeneity, resource availability, and
seasonal hydrological fluctuations (Byju et al.
2024a, 2025a). Their specific habitat requirements and trophic positions make
birds sensitive to environmental change and reliable bioindicators for
assessing ecosystem health and the impacts of anthropogenic disturbances (Byju et al. 2024b; Kumar et al. 2025).
In the Indian subcontinent,
coastal wetlands, estuaries, and mangrove systems along both the east and west
coasts provide crucial habitats for a vast array of resident and migratory
birds (Byju et al. 2023a,b, 2025b) and serve as vital
stopover and wintering grounds within the Central Asian Flyway (CAF). Recent
avifaunal studies from diverse coastal sites such as the Gulf of Mannar lagoons (Byju et al.
2025c,d), islands (Byju et al. 2023c), and Muthukkad backwaters on the eastern coast (Shree & Malathi 2024), and Changaram
wetlands (Anand et al. 2023), on the western coast, highlight the regional
significance of these understudied habitats for sustaining biodiversity.
However, many smaller, ecologically complex estuaries remain under-surveyed,
leading to gaps in our understanding of local species assemblages and their
conservation needs.
The Poovar
estuary, situated at the southern tip of Kerala on the southwestern coast of
India, represents one such understudied coastal mosaic. This dynamic system,
formed by the confluence of the Neyyar River,
backwaters, the Arabian Sea, and fringing mangroves creates a heterogeneous
landscape of sandbars, mudflats, freshwater marshes, and anthropogenically
modified areas. The region is important along the CAF, providing critical
resources for foraging, roosting, and breeding birds. In this context,
systematic baseline studies are imperative for generating robust scientific
data to inform conservation planning and sustainable management. This study
represents the first systematic, habitat-based avifaunal assessment of the Poovar region. The research objectives are to compile a
systematic checklist of bird species, documenting their relative abundance,
habitat associations, and temporal occurrence, thus addressing a significant
knowledge gap in the avifauna of Kerala’s coast, and provide insights for local
and regional conservation strategies.
Materials
and Methods
Study area
Poovar is a coastal village in the Neyyattinkara Taluk of Thiruvananthapuram District, Kerala,
India (8.3002–8.3502 oN; 77.0336–77.0836 oE). It lies within the Poovar
Grama Panchayat under the Parassala
Block Panchayat. The area represents a unique ecological confluence of marine,
estuarine, riverine, mangrove, and terrestrial ecosystems, supporting high
habitat heterogeneity and avian diversity. Four distinct habitats were selected
for the present study (Image 1): 1. Poovar Backwater:
A 6-km stretch of the Neyyar River backwater (50–200
m wide), providing feeding and roosting habitats for waterbirds;
2. Poovar Beach: A ~12 km sandy shoreline where the Neyyar River meets the Arabian Sea, important for migratory
shorebirds and coastal avifauna; 3. Poovar Mangroves:
Estuarine fringes (5 km, 20–80 m wide) with dense mangrove vegetation,
functioning as nurseries and foraging sites; and 4. Human-settled areas:
Settlements, agricultural fields, and transport corridors (~7 km), supporting synanthropic species.
Bird surveys
Avifaunal surveys were conducted
from August 2024 to July 2025. Point counts were conducted with fixed points
established across habitats, using 10-minute observations within a 50-m radius
(Bibby et al. 2000). Surveys were conducted monthly, once at 0700–1000 h and
again at 1600–1800 h, coinciding with peak bird activity. Birds were observed
using Olympus 8 × 40 binoculars and photographed with a Nikon Z6III and NIKKOR
200–500 mm lens. Double-counting was avoided by recording flight directions and
repeated movements, and avoiding species count coming from behind the observer.
Permanent survey routes and observation points across habitats were monitored
once per month to assess temporal variation. Birds were identified using
standard field guides (Grimmett et al. 2011). We
followed the taxonomy, nomenclature and Indian Wildlife Protection Act (IWPA)
status based on IOC World Bird List v.14.1 (Praveen et al. 2023; Gill et al.
2024). Conservation status was assessed using the IUCN Red List (IUCN 2025).
Relative diversity index (RDi) of the avian families was calculated with the
following formula (Torre-Cuadros et al. 2007):
Number
of avifaunal species in a family
RDi =
–––––––––––––––––––––––––––––––––––––– x 100 Total number of avifaunal species
Multiple correspondence analysis
(MCA) was performed to analyze the association between bird species and habitat
categories. MCA is an extension of correspondence analysis designed for
multivariate categorical data, allowing simultaneous visualization of
relationships between species occurrences and habitat types in a
low-dimensional space (Greenacre & Blasius 2006).75% confidence ellipses
were added around habitat groupings to represent the dispersion and overlap of
species compositions within each habitat. Overlap among ellipses indicates
shared species assemblages and distributions across habitats. The analysis was
done using R software version 4.5.1. (R core team 2025).
Results
and Discussion
During the
study period, a total of 88 avian species were recorded, representing 17 orders
and 37 families, which included 70 genera. Poovar
avifauna comprised 46 species of waterbirds and 42 species
of landbirds. Among the waterbirds,
order Charadriiformes predominated (n = 25 species),
with four families, followed by Pelecaniformes (n =
12) with two families. Landbirds were majorly
represented by Passeriformes (n = 24), with 14 families, followed by Coraciiformes (6 species) (Image 2).
The family-wise analysis of
avifauna revealed variation in relative diversity. Laridae
(14 species, RDi 16.0%) was the most dominant,
followed by Ardeidae (9 species, RDi
10.2%) and Scolopacidae (6 species, RDi 6.8%). Alcedinidae, Charadriidae, & Sturnidae (4
species each, RDi 4.5%); Accipitridae,
Corvidae, Cuculidae, Dicruridae, Motacillidae, & Threskiornithidae (3 species each, RDi
3.4%); and Ciconiidae, Cisticolidae,
Meropidae, & Phalacrocoracidae
(2 species each, RDi 2.2%), followed the dominance.
The remaining 21 families recorded the lowest species richness (one species
each and RDi 1.1%) (Image 3).
Feeding guild analysis showed
that while 34% of the total avifauna were insectivorous (30 species), the
remaining were carnivorous (22 species), omnivorous (18 species) and
piscivorous (15 species). There were only two nectarivores, Pale-billed
Flowerpecker Dicaeum erythrorhynchos,
which is also a frugivore, and Purple-rumped Sunbird Leptocoma zeylonica.
Another frugivore recorded was Rose-ringed Parakeet Psittacula
krameri (Image 4). According to migratory status,
resident birds constituted 64% (56 species) of species, while winter visitors
accounted for the rest.
Of the
species documented, 86 were categorized as ‘Least Concern’, the Oriental Darter
Anhinga melanogaster as ‘Near Threatened’, and the River Tern Sterna aurantia as ‘Vulnerable’. As per the Indian Wildlife
Protection Act (IWPA) 2022, eight species were under Schedule I, 79 species
under Schedule II, and one species, House Crow Corvus
splendens, is Not Scheduled (Table 1).
The peak
counts of most of the birds recorded during the study period were from October
to February. Black Kite Milvus migrans was the
most abundant landbird species (n = 450 in December),
followed by House Crow (n = 200 in July) and Brahminy Kite Haliastur
indus (n = 156 in September). Both the kite
species were recorded in all kinds of habitats - backwater, mangrove, urban and
beach area, typical of their scavenging nature. One individual of another
raptor, Shikra Accipiter badius,
was recorded in November in the backwater and mangrove area. Among the waterbirds, the most abundant species were Glossy Ibis Plegadis falcinellus (n
= 60 in November), Lesser Black-backed Gull Larus
fuscus (n = 56 in January), Greater Crested Tern Thalasseus bergii and
Brown-headed Gull Chroicocephalus brunnicephalus (n = 34 each in March and February,
respectively), and Tibetan Sand Plover Anarhynchus
atrifrons (n = 30 in December) (Image 5).
The Multiple correspondence
analysis (MCA) showed clear habitat-associated assemblages of bird species
across the study area (Image 6). The first two dimensions (dim) explained 38.7%
of the total variance (dim.1: 22.14%, eigenvalue 0.4059; dim.2: 16.55%,
eigenvalue 0.3034), indicating that these axes captured the most significant
patterns in species-habitat relationships (Table 2). Although subsequent
dimensions each explained smaller proportions of variance, their contribution
declined gradually, and interpretation was therefore focused on the first two
axes for visualization. Species characteristic of beaches and sandbars, such as
terns, plovers, and jaegers, clustered distinctly with the beach vector. While
other species like Gulls, Tibetan Sand Plover, few species of terns like Common
Tern Sterna hirundo, Little Tern Sternula albifrons,
and Greater Crested Tern show overlapping habitat preferences of beaches,
backwater, and mangroves. Backwater habitats showed a mixed assemblage of
herons, egrets, storks, and ibises, with the majority of them overlapping with
farmland habitats. Specific habitats, such as agricultural lands, were found to
support the highest species richness of the insectivorous birds, whereas the
wetland habitats were strongly associated with birds in the piscivorous and
carnivorous guild (Panda et al. 2021). Agricultural fields supporting
wetland birds are well documented in recent studies (Byju
et al. 2024c).
Urban
habitats or the human settlement areas formed a discrete group in Poovar, primarliy occupied by
Passeriformes such as mynas, sparrows, coucal, koel, Common Tailor-bird Orthotomus
sutorius, and pigeons. Very few landbird species, like Oriental Magpie Robin Copsychus saularis,
Red-whiskered Bulbul Pycnonotus jocosus, among others, showed overlapping habitat
preferences with both urban areas and farmlands. The size of each ellipse in
the MCA plot represents the dispersion of species within that habitat category;
larger ellipses indicate greater variability in species composition, just like
composition, particularly in the backwater habitat (Image 7). In the MCA
biplot, habitats represented by longer vectors, such as beach and urban areas,
show species assemblages that are more distinct from the overall community,
whereas shorter vectors indicate less exclusive species associations and
greater compositional overlap, as observed for backwater and mangrove habitats.
Along dimension 1, beach and mangrove habitats are positioned on the negative
axis, while urban and farmland habitats occur on the positive axis, reflecting
contrasting assemblages. Backwater habitat occupies an intermediate position
and overlap with other habitats, highlighting their transitional species
composition.
Diversity,
abundance, and distribution of waterbirds are
determined by the distinctive characteristics of habitats and factors such as
food availability, vegetation characteristics, water availability, water
quality, among others (Ma et al. 2010). Waterbirds
comprised the majority of the avifaunam community in Poovar, with the order Charadriiformes
being the dominant order. This aligned with the trend in other coastal
ecosystems (Byju et al. 2025e), where species of Charadriidae and Laridae were the
most abundant because of suitable feeding and roosting grounds, especially in heterogeneous
habitats like estuaries, backwater, mangroves, and sandy beaches (Manikannan et al. 2012; Byju et
al. 2024b). Such habitat mosaics offer diverse foraging substrates and water
regimes, enabling partitioning of resources between different bird groups. Some
bird species are associated with more than one habitat (Lorenzón
et al. 2016). The occurrence of the same species in multiple habitat types
indicates that the ecological and resource requirements of those species are
fulfilled in both environments (Sharma et al. 2024). Similar patterns have
been recorded in the Ashtamudi and Vembanad estuarine complexes of Kerala (Narayanan et al.
2011) and Perungulam wetland in Tamil Nadu (Mathibalan et al. 2026), where structurally complex
wetlands supported higher bird diversities.
Conclusion
By sustaining diverse avian
assemblages and facilitating breeding and seasonal occupancy, Poovar functions as a key node within the broader wetland
network used by resident and migratory birds.
Table 1. Species list with
IUCN Red List status, migration status, WPA status, along
with feeding guilds and habitats.
|
Orders |
Families |
Common name |
Scientific name |
WPA Schedule |
IUCN Red List status |
Migratory status |
Feeding guild |
Major habitats |
|
Accipitriformes |
Accipitridae |
Black Kite |
Milvus migrans
(Boddaert, 1783) |
I |
LC |
R |
C |
BW, MG, BC, UA |
|
Brahminy Kite |
Haliastur indus (Boddaert, 1783) |
I |
LC |
R |
C |
BW, MG, BC, UA |
||
|
Shikra |
Accipiter badius
(Gmelin, 1788) |
I |
LC |
R |
C |
BW, MG |
||
|
Caprimulgiformes |
Apodidae |
Asian Palm Swift |
Cypsiurus balasiensis (Gray, JE, 1829) |
II |
LC |
R |
I |
UA, FL |
|
Columbiformes |
Columbidae |
Rock Pigeon |
Columba livia
(Gmelin, JF, 1789) |
II |
LC |
R |
O |
UA |
|
Coraciiformes |
Alcedinidae |
Common Kingfisher |
Alcedo atthis (Linnaeus, 1758) |
II |
LC |
R |
P |
BC, BW, MG |
|
Pied Kingfisher |
Ceryle rudis (Linnaeus, 1758) |
II |
LC |
R |
P |
BW, MG |
||
|
Stork-billed Kingfisher |
Pelargopsis capensis (Linnaeus, 1766) |
II |
LC |
R |
C |
BW, MG |
||
|
White-throated Kingfisher |
Halcyon smyrnensis
(Linnaeus, 1758)
|
II |
LC |
R |
C |
BW, MG |
||
|
Meropidae |
Asian Green Bee-eater |
Merops orientalis (Latham, 1801) |
II |
LC |
R |
I |
BW, MG |
|
|
Blue-tailed Bee-eater |
Merops philippinus (Linnaeus, 1767) |
II |
LC |
WV |
I |
BW, MG |
||
|
Cuculiformes |
Cuculidae |
Asian Koel |
Eudynamys scolopaceus (Linnaeus, 1758) |
II |
LC |
R |
O |
UA |
|
Greater Coucal |
Centropus sinensis (Stephens, 1815) |
II |
LC |
R |
O |
UA |
||
|
Pied Cuckoo |
Clamator jacobinus (Boddaert, 1783) |
II |
LC |
WV |
I |
FL |
||
|
Galliformes |
Phasianidae |
Peregrine Falcon |
Falco peregrinus
(Tunstall,
1771) |
I |
LC |
WV |
C |
BC, UA |
|
Passeriformes |
Acrocephalidae |
Blyth’s Reed Warbler |
Acrocephalus dumetorum (Blyth, 1849) |
II |
LC |
WV |
I |
BW |
|
Cisticolidae |
Ashy Prinia |
Prinia socialis (Sykes, 1832) |
II |
LC |
R |
I |
BW, UA |
|
|
Common Tailorbird |
Orthotomus sutorius (Pennant, 1769) |
II |
LC |
R |
I |
UA |
||
|
Corvidae |
House Crow |
Corvus splendens (Vieillot, 1817) |
Not sche-duled |
LC |
R |
O |
UA |
|
|
Large-billed Crow |
Corvus macrorhynchos (Wagler,
1827) |
II |
LC |
R |
O |
UA, BC |
||
|
Rufous Treepie |
Dendrocitta vagabunda (Latham, 1790) |
II |
LC |
R |
O |
BW |
||
|
Dicruridae |
Ashy Drongo |
Dicrurus leucophaeus (Vieillot, 1817) |
II |
LC |
R |
I |
BW, FL |
|
|
Greater Racket-tailed Drongo |
Dicrurus paradiseus (Linnaeus, 1766) |
II |
LC |
R |
I |
BW, FL |
||
|
Black Drongo |
Dicrurus macrocercus (Vieillot, 1817) |
II |
LC |
R |
I |
BW, FL |
||
|
Hirundinidae |
Barn Swallow |
Hirundo rustica (Linnaeus, 1758) |
II |
LC |
WV |
I |
BW, FL |
|
|
Laniidae |
Brown Shrike |
Lanius cristatus (Linnaeus, 1758) |
II |
LC |
WV |
I |
BW, FL |
|
|
Motacillidae |
Paddyfield Pipit |
Anthus rufulus (Vieillot, 1818) |
II |
LC |
R |
I |
BW, FL |
|
|
White-browed Wagtail |
Motacilla maderaspatensis (Gmelin,
JF, 1789) |
II |
LC |
R |
I |
BW |
||
|
Grey Wagtail |
Motacilla cinerea (Tunstall, 1771) |
II |
LC |
WV |
I |
BW |
||
|
Muscicapidae |
Oriental Magpie-Robin |
Copsychus saularis (Linnaeus, 1758) |
II |
LC |
R |
I |
BW, FL, UA |
|
|
Nectariniidae |
Purple-rumped
Sunbird |
Leptocoma zeylonica (Linnaeus, 1766) |
II |
LC |
R |
N |
BW, FL, UA |
|
|
Dicaeidae |
Pale-billed Flowerpecker |
Dicaeum erythrorhynchos (Latham, 1790) |
II |
LC |
R |
F/N |
BW, FL, UA |
|
|
Passeriformes |
Passeridae |
House Sparrow |
Passer domesticus
(Linnaeus,
1758) |
II |
LC |
R |
O |
FL, UA |
|
Sturnidae |
Brahminy Starling |
Sturnia pagodarum (Gmelin, JF, 1789) |
II |
LC |
R |
O |
FL, UA |
|
|
Common Myna |
Acridotheres tristis (Linnaeus, 1766) |
II |
LC |
R |
O |
FL, UA |
||
|
Jungle Myna |
Acridotheres fuscus (Wagler, 1827) |
II |
LC |
R |
O |
FL, UA |
||
|
Rosy Starling |
Pastor roseus (Linnaeus, 1758) |
II |
LC |
WV |
O |
BW, FL, UA |
||
|
Leiotrichidae |
Yellow-billed Babbler |
Argya affinis (Jerdon, 1845) |
II |
LC |
R |
O |
BW, FL, UA |
|
|
Pycnonotidae |
Red-whiskered Bulbul |
Pycnonotus jocosus (Linnaeus, 1758) |
II |
LC |
R |
O |
BW, FL, UA |
|
|
Piciformes |
Megalaimidae |
White-cheeked Barbet |
Psilopogon viridis (Boddaert, 1783) |
II |
LC |
R |
O |
BW, MG |
|
Picidae |
Black-rumped
Flameback |
Dinopium benghalense (Linnaeus, 1758) |
II |
LC |
R |
I |
BW, FL |
|
|
Psittaciformes |
Psittaculidae |
Rose-ringed Parakeet |
Psittacula krameri (Scopoli, 1769) |
II |
LC |
R |
F |
FL, UA |
|
Charadriiformes |
Charadriidae |
Greater Sand Plover |
Anarhynchus leschenaultii (Lesson, RP, 1826) |
II |
LC |
WV |
I |
BC |
|
Kentish Plover |
Anarhynchus alexandrinus (Linnaeus, 1758) |
II |
LC |
WV |
I |
BC |
||
|
Tibetan Sand Plover |
Anarhynchus atrifrons (Wagler, 1829) |
II |
LC |
WV |
I |
BC, BW |
||
|
Red-wattled
Lapwing |
Vanellus indicus (Boddaert, 1783) |
II |
LC |
R |
I |
BW, FL |
||
|
Laridae |
Bridled Tern |
Onychoprion anaethetus (Scopoli, 1786) |
II |
LC |
WV |
P |
BC |
|
|
Little Tern |
Sternula albifrons (Pallas, 1764) |
II |
LC |
WV |
P |
BC, BW, MG |
||
|
Common Tern |
Sterna hirundo
(Linnaeus,
1758) |
II |
LC |
WV |
P |
BC, BW, MG |
||
|
River Tern |
Sterna aurantia
(Gray, JE,
1831) |
I |
VU |
R |
P |
BC, BW |
||
|
Greater Crested Tern |
Thalasseus bergii (Lichtenstein, MHC, 1823) |
II |
LC |
WV |
P |
BC, BW, MG |
||
|
Lesser Crested Tern |
Thalasseus bengalensis (Lesson, RP, 1831) |
II |
LC |
WV |
P |
BC |
||
|
Sandwich Tern |
Thalasseus sandvicensis (Latham, 1787) |
II |
LC |
WV |
P |
BC |
||
|
Gull-billed Tern |
Gelochelidon nilotica (Gmelin, JF, 1789) |
I |
LC |
WV |
O |
BC, BW, MG |
||
|
Whiskered Tern |
Chlidonias hybrida (Pallas, 1811) |
II |
LC |
WV |
P |
BC, BW, MG |
||
|
Caspian Tern |
Hydroprogne caspia (Pallas, 1770) |
II |
LC |
WV |
P |
BC, BW, MG |
||
|
Lesser Black-backed Gull |
Larus fuscus (Linnaeus, 1758) |
II |
LC |
WV |
C |
BC, BW, MG |
||
|
Black-headed Gull |
Larus ridibundus (Linnaeus, 1766) |
II |
LC |
WV |
C |
BC, BW, MG |
||
|
Brown-headed Gull |
Chroicocephalus brunnicephalus (Jerdon,
1840) |
II |
LC |
WV |
C |
BC, BW, MG |
||
|
Pallas’s Gull |
Ichthyaetus ichthyaetus (Pallas, 1773) |
II |
LC |
WV |
C |
BC, BW, MG |
||
|
Scolopacidae |
Common Sandpiper |
Actitis hypoleucos (Linnaeus, 1758) |
II |
LC |
WV |
I |
BC, BW, MG, FL |
|
|
Sanderling |
Calidris alba (Pallas, 1764) |
II |
LC |
WV |
I |
BC |
||
|
Temminck's Stint |
Calidris temminckii (Leisler, 1812) |
II |
LC |
WV |
I |
BC |
||
|
Common Greenshank |
Tringa nebularia (Gunnerus, 1767) |
I |
LC |
WV |
I |
BC |
||
|
Wood Sandpiper |
Tringa glareola (Linnaeus, 1758) |
II |
LC |
WV |
I |
BC, FL |
||
|
Whimbrel |
Numenius phaeopus (Linnaeus, 1758) |
II |
LC |
WV |
I |
BC |
||
|
|
Stercorariidae |
Parasitic Jaeger |
Stercorarius parasiticus (Linnaeus, 1758) |
II |
LC |
WV |
C |
BC |
|
Ciconiiformes |
Ciconiidae |
Asian Openbill |
Anastomus oscitan (Boddaert, 1783) |
II |
LC |
R |
C |
BC, FL |
|
Painted Stork |
Mycteria leucocephala (Pennant, 1769) |
II |
LC |
R |
C |
BC, FL |
||
|
Gruiformes |
Rallidae |
White-breasted Waterhen |
Amaurornis phoenicurus (Pennant, 1769) |
II |
LC |
R |
O |
BW |
|
Pelicaniformes |
Ardeidae |
Eastern Cattle Egret |
Bubulcus coromandus (Boddaert, 1783) |
II |
LC |
R |
C |
BC, FL |
|
Great Egret |
Ardea alba (Linnaeus, 1758)
|
II |
LC |
R |
C |
BC, FL, MG |
||
|
Medium Egret |
Ardea intermedia (Wagler, 1829) |
II |
LC |
R |
C |
BC, FL, MG |
||
|
Grey Heron |
Ardea cinerea (Linnaeus, 1758) |
II |
LC |
R |
C |
BW, FL |
||
|
Purple Heron |
Ardea purpurea (Linnaeus, 1766) |
II |
LC |
R |
C |
BW, FL |
||
|
Indian Pond Heron |
Ardeola grayii (Sykes, 1832) |
II |
LC |
R |
C |
BW, FL |
||
|
Little Egret |
Egretta garzetta (Linnaeus, 1766) |
II |
LC |
R |
C |
BC, FL, MG |
||
|
Western Reef Heron |
Egretta gularis (Bosc, 1792) |
II |
LC |
R |
C |
BC, FL, MG |
||
|
Black-crowned Night Heron |
Nycticorax nycticorax (Linnaeus, 1758) |
II |
LC |
R |
C |
BW, FL |
||
|
Threskiornithidae |
Black-headed Ibis |
Threskiornis melanocephalus (Latham, 1790) |
II |
LC |
R |
I |
BW, FL |
|
|
Eurasian Spoonbill |
Platalea leucorodia (Linnaeus, 1758) |
I |
LC |
R |
I |
BW, FL |
||
|
Glossy Ibis |
Plegadis falcinellus (Linnaeus, 1766) |
II |
LC |
R |
I |
BW, FL |
||
|
Procellariiformes |
Oceanitidae |
Wilson’s Storm Petrel |
Oceanites oceanicus
(Kuhl,
1820) |
II |
LC |
WV |
P |
BC |
|
Suliformes |
Anhingidae |
Oriental Darter |
Anhinga melanogaster (Pennant, 1769) |
II |
NT |
R |
P |
BW, FL |
|
Phalacrocoracidae |
Indian Cormorant |
Phalacrocorax fuscicollis (Stephens, 1826) |
II |
LC |
R |
P |
BW, MG |
|
|
Little Cormorant |
Microcarbo niger (Vieillot, 1817) |
II |
LC |
R |
P |
BW, MG |
||
|
Podicipediformes |
Podicipedidae |
Little Grebe |
Tachybaptus ruficollis (Pallas, 1764) |
II |
LC |
R |
O |
BW, MG |
|
Anseriformes |
Anatidae |
Lesser Whistling Duck |
Dendrocygna javanica (Horsfield, 1821) |
II |
LC |
R |
O |
BW, MG |
WPA status: I—Schedule I |
II—Schedule II. IUCN Red List status:
LC—Least Concern | VU—Vulnerable | NT—Near Threatened. Migration status:
WV—Winter visitor | R—Resident. Feeding guild: C—Carnivore | I—Insectivore | O—Omnivore
| P—Piscivore | F—Frugivore | N—Nectarivore.
Habitats: BW—Backwater | BC—Beach | MG—Mangrove | FL—Farmlands.
Table 2. Eigenvalues and percent variance explained by each
multiple correspondence analysis dimension.
|
Dimensions |
Eigenvalue |
Variance percent |
|
Dim.1 |
0.4059 |
22.14 |
|
Dim.2 |
0.3034 |
16.55 |
|
Dim.3 |
0.2198 |
11.99 |
|
Dim.4 |
0.1719 |
9.37 |
|
Dim.5 |
0.1711 |
9.33 |
|
Dim.6 |
0.1666 |
9.09 |
|
Dim.7 |
0.1411 |
7.69 |
|
Dim.8 |
0.1067 |
5.82 |
|
Dim.9 |
0.0581 |
3.17 |
|
Dim.10 |
0.0484 |
2.64 |
|
Dim.11 |
0.0397 |
2.16 |
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