Journal of Threatened
Taxa | www.threatenedtaxa.org | 26 September 2026 | 18(9): 29571–29582
ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print)
https://doi.org/10.11609/jott.10681.18.9.29571-29582
#10681 | Received 19 May 2026 | Final received 10 July 2026 | Finally accepted
28 August 2026
Avian community structure in a
human-impacted forest landscape: insights from Amangarh
Tiger Reserve, Uttar Pradesh, India
Vijay Pratap Singh 1
, Sajid Reza 2 , Sharad Kumar 3 , Meraj Anwar 4
& Afifullah Khan 5
1,2 Wildlife Institute of India, Chandrabani, Dehradun, Uttarakhand 248001, India.
3,5 Department of Wildlife Sciences,
Aligarh Muslim University, Aligarh, Uttar Pradesh 202002, India.
4 WWF-India Terai
Arc Landscape field office, Haldwani, Nainital,
Uttarakhand 263139, India.
1 pratapsingh.vijay5@gmail.com, 2
thesajidreza@gmail.com, 3 sharadamu@gmail.com, 4 anwar.meraj@gmail.com,
5 afifkhan@rediffmail.com (corresponding author)
Editor: H. Byju,
Coimbatore, Tamil Nadu, India. Date
of publication: 26 September 2026 (online & print)
Citation: Singh,
V.P., S. Reza, S. Kumar, M. Anwar & A. Khan (2026). Avian
community structure in a human-impacted forest landscape: insights from Amangarh Tiger Reserve, Uttar Pradesh, India. Journal of Threatened Taxa 18(9): 29571–29582. https://doi.org/10.11609/jott.10681.18.9.29571-29582
Copyright: © Singh 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: This research was supported by WWF-India.
Competing interests: The authors declare no competing interests.
Author details: Vijay Pratap Singh is a researcher at the Wildlife Institute of India and a Ph.D. scholar in the Department of Wildlife Sciences, Aligarh Muslim University. Currently his research focuses on Freshwater ecology. During his M.Sc., he also conducted research on avian ecology, bird communities, habitat use, and ecological patterns. Sajid Reza is a PhD scholar at the Wildlife Institute of India. He completed his masters in Wildlife Sciences from Aligarh Muslim University. His research focuses on the ecology and human-carnivore interactions of large carnivores in human-dominated landscapes in central India. Dr. Meraj Anwar received a PhD in wildlife science and his research work focused on population status of tigers, its prey species and wildlife corridors in Terai Arc Landscape. He also has experience of telemetry studies on tigers and one horned rhinoceros. Dr. Sharad Kumar is an assistant professor in the Department of Wildlife Sciences, AMU, Aligarh, with extensive experience in wildlife research and conservation. His work focuses on large carnivores, birds, human-wildlife conflict, park-people relationship and protected-area management. He has led several research projects, and published widely in national and international journals. Dr. Afifullah Khan is a professor in the Department of Wildlife Sciences, AMU, Aligarh, specializing in wildlife ecology, and biodiversity conservation. His research centres on understanding species-habitat relationships and community dynamics to inform effective wildlife management strategies He also contributes significantly to the Management Effectiveness Evaluation (MEE) of protected areas across India.
Author contributions: VPS conceived the study, designed the study, conducted the fieldwork, analysed the data, and prepared the initial manuscript. SR contributed to study design and conducted the fieldwork. MA contributed to study design and field supervision. SK contributed to statistical analysis, writing, supervision and manuscript review. AK contributed to study design, Supervision, data interpretation, and critical revision of the manuscript.
Acknowledgements: We gratefully acknowledge the financial support provided by the WWF-India. We extend our sincere appreciation to the Uttar Pradesh Forest Department for their invaluable assistance, with special thanks to the DFO, Shri M. Semmaran, IFS and the entire forest department staff of Amangarh Tiger Reserve for their exceptional support in facilitating data collection. We would also like to thank Shariq Safi and Pooran Rana for their support during our fieldwork.
Abstract: Habitat degradation and loss due
to anthropogenic pressures are the primary threats to biodiversity,
particularly in tropical forests. Monitoring bird communities provides valuable
insights into the environmental status of both natural and human-modified
ecosystems. In this study (February–April 2021), the point count method was
used to assess avian species richness, diversity, and density in Amangarh Tiger Reserve (ATR)—a human-impacted forest area,
aiming to understand its ecological importance and conservation potential. A
proportionately stratified random sampling strategy was used for point count
surveys across multiple habitat types. Species were identified, counted, and categorised by feeding guilds, and diversity indices were
calculated. Bird density was calculated using Distance 7.3 software. A
total of 110 bird species were recorded, indicating noteworthy species
richness. Mixed forest exhibited the highest diversity, richness, and density
(2029.7 birds/km², 95% CI: 1732.2–2378.2), likely due to its structural
complexity. In contrast, teak plantations supported the lowest bird diversity,
likely due to monoculture and low structural complexity. The riverbed had the
lowest richness and density (1038 birds/km², 95% CI: 245.9–4381.1).
Insectivores were the most abundant group, suggesting good ecological integrity
of the region. This study highlights the ecological value of ATR for avian
conservation, particularly the role of habitat heterogeneity and its mixed
forests. Long-term monitoring is necessary to guide conservation planning and
maintain the stability of bird communities in human-impacted landscapes such as
ATR.
Keywords: Avian density, avian diversity,
avian richness, biodiversity, birds, community ecology, distance sampling,
feeding guilds, habitat heterogeneity, point count.
Abbreviations: ATR—Amangarh
Tiger Reserve | CR-—Carnivore | EN—Endangered | FR—Frugivore | GR—Granivore | IN—Insectivore | LC—Least Concern |
NC—Nectivore | NT—Near Threatened | OM—Omnivore | PI—Piscivore | VU—Vulnerable.
Introduction
Birds are a highly diverse and
widely distributed group of vertebrates, with more than 11,000 species found
globally (BirdLife International 2023; Clements et
al. 2023; Rheindt et al. 2025). India harbours remarkable avian diversity, supporting around 12% of
the world’s bird species (Praveen & Jayapal
2025). This remarkable avian diversity can largely be attributed to India’s
diverse landforms, vast altitudinal gradient, and highly varied climatic
conditions, which give rise to a wide range of vegetation types and
environments in the country. Birds inhabit a diverse range of environments and
play a crucial role in ecosystem functioning, including pollination, seed
dispersal, pest control, and nutrient cycling, making them vital components of
biodiversity (Sekercioglu 2006).
Forest landscapes are undergoing
rapid changes due to various anthropogenic activities, leading to modifications
in vegetation structure and loss of biodiversity (Morris 2010; Haddad et al.
2015; Brancalion et al. 2025; Yang et al. 2025). Monitoring
human-impacted forest landscapes is crucial for understanding the effects of
these disturbances on natural ecosystems and for implementing effective
corrective measures. Due to their sensitivity to environmental changes and wide
distribution, birds are effective and reliable indicators of environmental
health and stability and are frequently used to monitor ecosystem health
(Canterbury et al. 2000; Mansfield et al. 2024; Naveen et al. 2026; Njuguna et
al. 2026). Monitoring bird communities provides valuable insights into
ecological dynamics and the impacts of anthropogenic pressures on natural
ecosystems in a specific area; therefore, understanding the structure of bird
communities is crucial for long-term environmental conservation (Gregory &
Van Strien 2010; Byju et
al. 2026). Species richness, abundance, and community composition are key
characteristics of communities that ecologists often examine (Magurran 2004). Another important approach to understanding
bird community structure is based on their feeding guilds and habitat use (Thiollay 1995; Clough et al. 2009). A guild is a
fundamental concept in avian ecology, referring to a group of bird species that
coexist within a community by utilising similar types
of environmental resources (Balestrieri et al. 2015).
Different guilds exhibit distinct tolerance thresholds and resource utilisation strategies that are shaped by the specific
environmental conditions they inhabit. These variations are largely governed by
multiple biotic and abiotic factors, including food availability, vegetation
structure, habitat complexity, and the presence or absence of predators and
competitors. Such ecological parameters play a crucial role in determining the
distribution, abundance, and functional roles of guild members within an
ecosystem (Katuwal et al. 2016; Mathibalan
et al. 2026).
Despite their importance in
monitoring the health of ecosystems, there is a notable lack of comprehensive
scientific studies on birds in the human-impacted forests, especially in the Terai Arc Landscape. This landscape harbours
exceptionally rich avifauna — for example, 330 species recorded in Dudhwa National Park (Javed &
Rahmani 1998), and over 400 species in Terai Arc protected areas (Safi et al. 2024). However, most
ornithological accounts from the Terai region have
been limited to species checklists or opportunistic sightings, documenting
presence but not quantifying population densities or spatial patterns.
Consequently, robust studies estimating bird abundance using standardised methods, such as point counts or line
transects, remain scarce, leaving critical gaps in conservation planning (Kidwai et al. 2013). Amangarh
Tiger Reserve (ATR), which forms a multiple-use zone of the Corbett Tiger Reserve,
is subject to various anthropogenic pressures, including livestock grazing,
fuelwood extraction, and the collection of non-timber forest products by locals
(Reza et al. 2024). Despite high anthropogenic pressures, ATR remains a
significant forest landscape, serving not only as an important area for tiger
conservation but also as a refuge for a wide range of other wildlife species,
including avifauna, mammals, reptiles, and insects (Reza et al. 2024).
Important mammalian species of ATR include Leopard Panthera
pardus, Rusty-spotted Cat Prionailurus
rubiginosus, Asian Elephant Elephas maximus,
Sambar Rusa unicolor, and Chital Axis
axis, among others. Considering its ecological
value, it is an ideal site for initiating bird monitoring and ecological studies.
The present study aims to assess the bird community structure in the ATR,
focusing on species richness, diversity, abundance, and density. The research
seeks to enhance the understanding of the bird community of the region and
contribute to broader conservation initiatives.
Study Area
The study was conducted in the
ATR, spanning over an area of 80.60 km2. The reserve is located in
the Bijnor district of Uttar Pradesh (Image 1). The
ATR was originally part of Corbett National Park before the state of Uttar
Pradesh was bifurcated. Following the bifurcation of Uttar Pradesh, a major
part of Corbett National Park became part of Uttarakhand, while the Amangarh range remained within the state of Uttar Pradesh.
In 2012, the Amangarh range of Bijnor
Forest Division was designated as a buffer zone of the Corbett Tiger Reserve,
thereby integrating the area into the tiger reserve. Biogeographically, ATR is
part of the regional subdivision (Terai Bhabar tract) of the Upper Gangetic Plains, a low-lying
land stretch along the sub-Himalayan Shivalik ridges
(Rodgers & Panwar 1988). The prominent vegetation in the Terai region is tropical moist deciduous forest (Champion
& Seth 1968; Rodgers & Panwar 1988). The ATR vegetation can be further categorised into the following types: Sal-dominated forest,
Teak plantation, mixed forest, grassland, and scrubland. The terrain is mainly
plain with a mean elevation of 290 m (ranging 246–373 m), rarely becoming
undulating in certain areas. The area has three major seasonal rivers and many
small water channels, which become active during the monsoon and feed water to
the area.
A land cover map of the ATR was
prepared using a Landsat 8 (ESRIGRID; projection, UTM; datum, WGS 1984; cell
size 30 m) operational land imager (OLI) image acquired on 11.iii.2021. The OLI
data were processed using ArcGIS Pro 10.8.2 software (Esri,
2021), and through supervised classification, six distinct habitat types were
identified within the study area (Image 2).
Methods
The study was conducted between
February and April 2021, using the Point Count method (Verner 1985) to collect
data for bird diversity, community structure, and abundance estimates. This
method involved monitoring birds at established fixed point count stations
across various habitats within the study area. Point counts were conducted by a
team of two to three observers at 0600–1100 h and 1500–1900 h, as bird activity
is highest during these times (Rutt et al. 2023;
Singer et al. 2025). After reaching a point count station, the team waited quietly
for five minutes to allow birds disturbed by their presence to resume normal
activity. This acclimatisation period minimised person-induced bias and ensured random
distribution of birds around the point count station. Data were collected for
all birds seen around the point count station over a 10-minute observation
period. Data on bird species, flock size, and radial distance (using an IR
range finder) from the points were collected. Each point count station was
monitored six times during the study period, three times during both evening
and morning hours. Species identifications were performed by experienced
observers using Grimmett et al. (2011) and Grewal et
al. (2016).
A total of 60 points were laid
using a stratified random sampling strategy across these six habitat types. The
number of points in a particular habitat type was almost proportional to the
area under that habitat type (Table 1). A minimum distance of 400 m was
maintained between two adjacent points to ensure that bird detections from different
points are statistically independent.
Bird density was determined using
the software DISTANCE 7.3 (Thomas et al. 2010). Models with different
combinations of key functions and series expansions were tried and the final
model for the analysis was chosen based on Akaike’s information criteria (AIC)
values (Akaike 1974; Burnham & Anderson 2002), and chi-square statistics
were used to determine the ‘goodness of fit’ of each function (Burnham et al.
1980; Buckland et al. 2001). Species diversity (Shannon-Wiener) and richness (Margalef) indices were calculated using software Past 4.03
(Paleontological Statistics Software package for education and data
analysis, Hammer et al. 2001), while relative
abundance and species occurrence were calculated using the following formulas:
Total individuals of a species
Relative abundance of a species =
–––––––––––––––––––––––– X 100
Total
individuals of all species
Number of times a species recorded
Occurrence of a species =
–––––––––––––––––––––––––––––– X 100
Total effort
Sixty point-count stations were
monitored six times each, yielding a total effort of 360 point-count occasions.
As data satisfied the assumptions of normality, a one-way ANOVA was performed
to determine differences among habitat types for richness and diversity
indices. Feeding guilds were determined using dietary information from EltonTraits 1.0 (Wilman et al.
2014). Species were categorised based on the
predominant food items in their diet and grouped into major feeding guilds such
as insectivores, frugivores, granivores, etc. In
cases where no single food category was clearly dominant, species were
classified into combined guilds.
Limitations of the study: The
findings of the study should be interpreted in light of certain limitations.
First, field surveys were conducted for a limited period and did not encompass
all the seasons, particularly the monsoon season. As bird communities often
exhibit seasonal variations in species composition and abundance due to
migration and resource availability, the observed patterns may not fully
represent avian diversity and population dynamics within the study area.
Second, although distance sampling methods were employed to estimate bird
density, detection probability may have varied among habitats. While the
distance sampling framework accounts for imperfect detection and attempts to
correct biases, residual errors associated with observer ability, vegetation
density, species-specific detectability, and environmental conditions may still
influence density estimates. Despite these limitations, the study provides
valuable baseline information on avian diversity, community structure and
density and establishes a foundation for future long-term and year-round
monitoring efforts.
Results
Avian diversity and ecological
traits
A total of 110 species (109
identified and one unidentified) were recorded during the study, representing
14 orders and 45 families. The Passeriformes were the largest order, containing
61 bird species. Among families, Muscicapidae,
with 10 species, emerged as the most species-rich family, followed by Picidae (9 species), Accipitridae
(6 species), and Columbidae (6 species). The highest
number of species was recorded in mixed forest (70 species), followed by
Sal-dominated forest (61 species), while the minimum number of species (21
species) was recorded in riverbed (Table 2).
Among the recorded species, one
species—Egyptian Vulture Neophron percnopterus—is ‘Endangered’; two species—Great
Hornbill Buceros bicornis,
and Great Slaty Woodpecker Mulleripicus
pulverulentus are ‘Vulnerable’; two
species—Cinereous Vulture Aegypius monachus and Red-breasted Parakeet Psittacula
alexandri—are ‘Near Threatened’; and the rest
(104 species) are ‘Least Concern’.
Categorisation of birds according to their
feeding guilds showed that the majority of bird species belong to insectivores
(n = 52, 46.85%), followed by omnivores (n = 20, 18.02%), frugivores (n = 12,
10.81%), granivores (n = 9, 8.11%), carnivores (n =
8, 7.21%), nectarivores (n = 2, 1.80%), and piscivores (n = 1, 0.90%). Five
species belonged to multiple feeding guilds (Image 3).
Bird density
Based on AIC values, the
hazard-rate model with simple polynomial adjustment was selected for bird
density estimation. The estimated bird density in the study area was 1,471
birds/km² (95% CI: 1313.6–1647.2), while the cluster density was 926.19
clusters/km² (95% CI: 828.7–1035.2), with a mean cluster size of 1.6
individuals and an effective detection radius (EDR) of 44.78 m (Table 3).
Estimates of relative abundance and occurrence indicated that the Plum-headed
Parakeet Psittacula cyanocephala,
Rose-ringed Parakeet Psittacula krameria,
and Yellow-throated Sparrow Gymnoris xanthocollis were the most common and abundant bird
species in the study area (Table 4). The estimates of bird density in different
habitat types showed that mixed forest had the highest density (2,029.7
birds/km², 95% CI: 1732.2–2378.2), followed by scrubland (1,928.6 birds/km²,
95% CI: 1325.9–2805.1), whereas the lowest density (1,038.0 birds/km², 95% CI:
245.94–4381.1) was recorded in riverbed (Table 2).
Bird species diversity and richness
The overall Shannon-Wiener
diversity and Margalef richness were 1.81 ± 0.06 SD
and 2.72 ± 0.12 SD, respectively. Among the different habitat types, mixed
forest had the highest diversity (3.06) and richness (9.59), while the lowest
diversity (1.88) and richness (4.22) were recorded in teak plantations and
riverbed, respectively (Table 2). An analysis of variance (ANOVA) revealed
statistically significant differences among habitat types for species richness
(F(5,54) = 7.938, p = 1.16e-05) and species diversity
(F(5,54) = 9.214, p = 2.19e-06).
Discussion
This study provides insights into
the avian species richness, density, and feeding guilds of the ATR, emphasising the ecological significance of this
human-impacted landscape for biodiversity conservation. The observation of 110
bird species (109 identified and one unidentified) within a relatively small
area (80.60 km²) reflects considerable species richness, underscoring the
importance of habitat heterogeneity in supporting avian biodiversity (Pineda-Diez
de Bonilla et al. 2012). The availability of diverse habitat types, such as
mixed forests, scrublands, and grasslands, provides a broad array of ecological
niches, allowing various bird species with different habitat preferences and
ecological requirements to thrive.
The presence of multiple feeding
guilds (i.e., considerable functional diversity) can also be related to high
habitat heterogeneity and the availability of diverse habitat types. The
dominance of insectivores can be attributed to their adaptability and the high
availability of insect prey in tropical landscapes (Pineda-Diez de Bonilla et
al. 2012; Panda et al. 2021; Ahmad & Khan 2022). Abundance and
diversity of insectivorous birds are also recognised
as sensitive indicators of environmental health, as they rely on the complexity
of vegetation and abundant insect populations (Kellermann
et al. 2008). Empirical and experimental studies often associate these traits
with greater temporal stability of ecosystem functions such as productivity,
pest control, and nutrient cycling (Tilman 1996; Hooper et al. 2005; Nyffeler et al. 2018). Their high abundance in the ATR
suggests that the area maintains a healthy trophic structure.
Results of diversity, richness,
and density highlight the ecological value of mixed forest habitats, where the
highest value of all three indices were recorded, likely due to their
structural complexity. Various studies suggest that the abundance of forest
birds is primarily driven by two distinct structural components: regenerating
vegetation (a developing cohort of saplings, shrubs, and closing canopy) and
legacy vegetation (retained biological structures such as large-diameter trees,
snags, and understory remnants) (Balestrieri et al.
2015, 2017; Czeszczewik et al. 2015; Basile et al.
2021). Mixed forests are structurally heterogeneous systems characterised
by the regenerating understory layers (seedlings, saplings, and shrubs) and
mature overstory trees (Gray et al. 2005; Hanle et
al. 2020). Due to their high vegetation diversity, they offer more foraging
opportunities, nesting sites, and microhabitats than other forest types.
Additionally, vegetation complexity creates edge habitats, which tend to harbour more bird species due to the overlap of species
from adjacent habitat types (Wiens 1989; Diaz 2006). Numerous studies have also
highlighted that increased vegetation structure and plant diversity are
strongly associated with richer and more abundant bird communities (Monkkonen 1994; Hobson & Bayne 2000a,b;
Machtans & Latour 2003; Archana et al. 2024).
In contrast, the teak plantation
had the lowest diversity, and the riverbed had the lowest richness and density.
Teak plantations are typically monocultures with poor understory and low
vegetation heterogeneity. Such structurally simplified and deciduous habitats
offer fewer resources and nesting opportunities, leading to reduced avian
diversity (Hartley 2002; Waltert et al. 2004).
Additionally, teak forests (in the Terai) tend to
lack native floral diversity, which can result in a decline in associated
faunal communities, particularly specialists that depend on diverse
plant-insect interactions. Riverbeds exhibited the lowest richness and density,
likely because dry riverbeds generally have sparse or low vegetation (gravel,
sand, and few shrubs) and no tall vegetation, offering few perches, nesting
substrates, or cover. Additionally, open riverbed ground has an extreme
microclimate (intense sun, heat, wind), and exposure to predators further
reduces bird survival. Despite low bird richness and density, riverbeds
contribute to landscape heterogeneity, further boosting the landscape-level
diversity.
The abundance of generalist
species, such as the Plum-headed Parakeet, in ATR indicates that some native
birds are capable of adapting to human-modified environments, particularly when
essential habitat features, such as food and nesting substrates, are retained.
However, this also highlights the need to monitor less adaptable, specialist
species, which may decline under increasing anthropogenic pressures.
Although this study establishes
ATR as an ecologically important area for bird conservation, it also
underscores the need for long-term monitoring to better understand temporal
changes in bird communities and the impacts of human activities on
biodiversity. Long-term studies would provide deeper insights into breeding
patterns, seasonal migration, habitat utilisation,
and the resilience of avian populations in the face of environmental change.
The present study provides
quantitative estimates of avian densities within a largely understudied region
of the Terai Arc Landscape. In addition, it
establishes essential baseline information on the structure and composition of
local bird communities and gives a comprehensive species checklist for ATR. The
study also highlights the role of habitat heterogeneity in maintaining avian
diversity, revealing both the conservation value of mixed forests and the
limitations of monoculture teak plantations.
Based on the study findings and
supporting field observations, several site-specific management interventions
are recommended for ATR. Anthropogenic pressures such as livestock grazing,
fodder, and fuelwood collection should be regulated to minimise
habitat degradation and facilitate habitat recovery. Livestock grazing may be
managed through rotational grazing practices and the promotion of stall
feeding. Restoration of degraded forest patches through the planting of native
mixed forest species should be prioritized to enhance structural complexity,
improve resource availability, and support a diverse bird community. The
management of riverine vegetation along streams and seasonal watercourses is
equally important, as these habitats provide essential foraging, nesting, and
refuge sites for numerous bird species. Furthermore, reducing dependence on
forest resources through the promotion of alternative energy sources,
energy-efficient cocking stoves, and livestock breed improvement initiatives
could help in reducing fuelwood and fodder extraction pressures. Collectively,
these measures would contribute to maintaining habitat heterogeneity and help
conserve biodiversity in the area.
Table 1. Proportion of different
habitat types and sampling efforts in Amangarh Tiger Reserve.
|
Habitat type |
Land cover area percentage (%) |
No. of point count stations |
Percentage of point count stations |
|
Dry river |
6.06 |
2 |
3 |
|
Grassland |
5.26 |
2 |
3 |
|
Mixed forest |
22.53 |
15 |
25 |
|
Sal dominated forest |
32.10 |
24 |
40 |
|
Scrubland |
10.16 |
4 |
7 |
|
Teak plantation |
23.09 |
13 |
22 |
Table 2. Density, diversity, and richness of
birds across different habitat types in Amangarh Tiger Reserve.
|
Habitat type |
No. of species recorded |
EDR ± SE (m) |
Density per sq
km |
95% Confidence interval |
Diversity |
Richness |
|
Mixed forest |
68 |
42.04 ± 0.83 |
2,029.7 |
1732.2, 2378.2 |
3.06 |
9.59 |
|
Sal dominated |
60 |
44.50 ± 0.83 |
1,291.5 |
1075.2, 1551.3 |
2.47 |
8.29 |
|
Teak plantation |
42 |
42.39 ± 1.06 |
1,243.2 |
985.35, 1568.7 |
1.88 |
6.48 |
|
Scrubland |
32 |
47.68 ± 1.91 |
1,928.6 |
1325.9, 2805.1 |
2.79 |
5.29 |
|
Grassland |
23 |
62.77 ± 2.89 |
1,082.0 |
663.40, 1764.9 |
2.64 |
4.34 |
|
River bed |
20 |
50.74 ± 3.38 |
1,038.0 |
245.94, 4381.1 |
2.67 |
4.22 |
Table 3. Avian group density,
average cluster size and overall density of birds in Amangarh
Tiger Reserve.
D—estimate of
density of birds | DS—estimate of density of
clusters | EDR—effective detection
radius | E(S)—estimate of expected value
of cluster size.
|
Parameter |
Point estimate |
Standard error |
Percent coef. of variation |
95% Confidence interval |
|
|
DS |
926.19 |
51.845 |
5.6 |
828.67 |
1035.2 |
|
E(S) |
1.5882 |
1.71E-02 |
1.07 |
1.5551 |
1.622 |
|
D |
1471 |
83.842 |
5.7 |
1313.6 |
1647.2 |
|
EDR |
44.785 |
0.49015 |
1.09 |
43.834 |
45.757 |
Table 4. Relative abundance, occurrence, IUCN Red List status, and feeding guilds of birds recorded
in Amangarh Tiger Reserve.
|
Order |
Family |
Common name |
Scientific name |
Relative abundance |
Occurrence |
IUCN Red List status |
Feeding guild |
|
Accipitriformes |
Accipitridae |
Changeable Hawk-Eagle |
Nisaetus cirrhatus |
0.03 |
0.28 |
LC |
CR |
|
|
|
Cinereous Vulture |
Aegypius monachus |
0.06 |
0.56 |
NT |
CR |
|
|
|
Crested Serpent Eagle |
Spilornis cheela |
0.38 |
3.61 |
LC |
CR |
|
|
|
Egyptian Vulture |
Neophron percnopterus |
0.03 |
0.28 |
EN |
CR |
|
|
|
Griffon Vulture |
Gyps fulvus |
0.03 |
0.28 |
LC |
CR |
|
|
|
Crested Honey Buzzard |
Pernis ptilorhynchus |
0.03 |
0.28 |
LC |
CR |
|
|
|
White-eyed Buzzard |
Butastur teesa |
0.06 |
0.56 |
LC |
CR |
|
Anseriformes |
Anatidae |
Green-winged Teal |
Anas crecca |
2.08 |
1.11 |
LC |
OM |
|
Bucerotiformes |
Bucerotidae |
Indian Grey Hornbill |
Ocyceros birostris |
3.44 |
23.33 |
LC |
FR |
|
|
|
Great Hornbill |
Buceros bicornis |
0.29 |
1.39 |
VU |
FR |
|
|
|
Oriental Pied Hornbill |
Anthracoceros albirostris |
0.23 |
1.11 |
LC |
FR |
|
Charadriiformes |
Burhinidae |
Indian Stone Curlew |
Burhinus indicus |
0.09 |
0.83 |
LC |
CR |
|
|
Charadriidae |
Red-wattled
Lapwing |
Vanellus indicus |
0.2 |
1.94 |
LC |
IN |
|
|
|
Yellow-wattled
Lapwing |
Vanellus malabaricus |
0.35 |
3.06 |
LC |
IN |
|
Columbiformes |
Columbidae |
Common Emerald Dove |
Chalcophaps indica |
0.03 |
0.28 |
LC |
FR |
|
|
|
Eurasian Collared Dove |
Streptopelia decaocto |
0.14 |
0.83 |
LC |
GR |
|
|
|
Oriental Turtle Dove |
Streptopelia orientalis |
1.53 |
11.67 |
LC |
GR |
|
|
|
Red Collared Dove |
Streptopelia tranquebarica |
0.09 |
0.83 |
LC |
GR |
|
|
|
Spotted Dove |
Spilopelia chinensis |
3.07 |
28.06 |
LC |
GR |
|
|
|
Yellow-footed Green Pigeon |
Treron phoenicopterus |
1.04 |
3.33 |
LC |
FR |
|
Coraciiformes |
Alcedinidae |
White-throated Kingfisher |
Halcyon smyrnensis |
0.09 |
0.83 |
LC |
PI |
|
|
Coraciidae |
Oriental Dollarbird |
Eurystomus orientalis |
0.03 |
0.28 |
LC |
IN |
|
|
|
Indian Roller |
Coracias benghalensis |
0.67 |
5.56 |
LC |
IN |
|
|
Meropidae |
Blue-bearded Bee-eater |
Nyctyornis athertoni |
0.06 |
0.56 |
LC |
IN |
|
|
|
Blue-tailed Bee-eater |
Merops philippinus |
1.39 |
10.28 |
LC |
IN |
|
|
|
Chestnut-headed Bee-eater |
Merops leschenaulti |
0.2 |
1.94 |
LC |
IN |
|
|
|
Asian Green Bee-eater |
Merops orientalis |
2.17 |
17.5 |
LC |
IN |
|
Cuculiformes |
Cuculidae |
Asian Koel |
Eudynamys scolopaceus |
0.06 |
0.56 |
LC |
OM |
|
Galliformes |
Phasianidae |
Grey Francolin |
Ortygornis pondicerianus |
0.4 |
1.67 |
LC |
GR |
|
|
|
Indian Peafowl |
Pavo cristatus |
0.03 |
0.28 |
LC |
OM |
|
|
|
Red Junglefowl |
Gallus gallus |
0.29 |
1.67 |
LC |
OM |
|
Gruiformes |
Rallidae |
White-breasted Waterhen |
Amaurornis phoenicurus |
0.03 |
0.28 |
LC |
OM |
|
Passeriformes |
Acrocephalidae |
Blyth's Reed Warbler |
Acrocephalus dumetorum |
0.32 |
1.11 |
LC |
IN |
|
|
Aegithinidae |
Common Iora |
Aegithina tiphia |
0.06 |
0.56 |
LC |
IN |
|
|
Alaudidae |
Ashy-crowned Sparrow-Lark |
Eremopterix griseus |
0.38 |
2.22 |
LC |
GR |
|
|
Campephagidae |
Indian Cuckooshrike |
Coracina macei |
0.06 |
0.28 |
LC |
IN |
|
|
|
Long-tailed Minivet |
Pericrocotus ethologus |
0.38 |
0.56 |
LC |
IN |
|
|
|
Rosy Minivet |
Pericrocotus roseus |
0.09 |
0.28 |
LC |
IN |
|
|
|
Small Minivet |
Pericrocotus cinnamomeus |
0.09 |
0.56 |
LC |
IN |
|
|
Chloropseidae |
Golden-fronted Leafbird |
Chloropsis aurifrons |
0.03 |
0.28 |
LC |
OM |
|
|
Cisticolidae |
Ashy Prinia |
Prinia socialis |
0.09 |
0.83 |
LC |
IN |
|
|
|
Grey-breasted Prinia |
Prinia hodgsonii |
0.09 |
0.83 |
LC |
IN |
|
|
Corvidae |
House Crow |
Corvus splendens |
0.03 |
0.28 |
LC |
OM |
|
|
|
Large-billed Crow |
Corvus macrorhynchos |
0.38 |
3.06 |
LC |
OM |
|
|
|
Rufous Treepie |
Dendrocitta vagabunda |
0.64 |
5.83 |
LC |
OM |
|
|
Dicaeidae |
Pale-billed Flowerpecker |
Dicaeum erythrorhynchos |
0.09 |
0.83 |
LC |
NT+FR |
|
|
|
Thick-billed Flowerpecker |
Pachyglossa agilis |
0.03 |
0.28 |
LC |
NT+FR |
|
|
Dicruridae |
Black Drongo |
Dicrurus macrocercus |
0.61 |
5 |
LC |
IN |
|
|
|
Greater Racket-tailed Drongo |
Dicrurus paradiseus |
0.17 |
1.67 |
LC |
IN |
|
|
|
Hair-crested Drongo |
Dicrurus hottentottus |
1.65 |
13.06 |
LC |
IN |
|
|
|
White-bellied Drongo |
Dicrurus caerulescens |
0.17 |
1.67 |
LC |
IN |
|
|
Estrildidae |
Scaly-breasted Munia |
Lonchura punctulata |
0.03 |
0.28 |
LC |
GR |
|
|
Fringillidae |
Common Rosefinch |
Carpodacus erythrinus |
0.55 |
1.94 |
LC |
GR |
|
|
Hirundinidae |
Grey-throated Martin |
Riparia chinensis |
0.12 |
0.56 |
LC |
IN |
|
|
Leiothrichidae |
Jungle Babbler |
Argya striata |
3.5 |
13.33 |
LC |
OM |
|
|
Locustellidae |
West Himalayan Bush Warbler |
Locustella kashmirensis |
0.17 |
0.56 |
LC |
IN |
|
|
Monarchidae |
Indian Paradise Flycatcher |
Terpsiphone paradisi |
0.09 |
0.83 |
LC |
IN |
|
|
Motacillidae |
Grey Wagtail |
Motacilla cinerea |
0.03 |
0.28 |
LC |
IN |
|
|
|
Tawny Pipit |
Anthus campestris |
0.06 |
0.56 |
LC |
IN |
|
|
|
Paddyfield Pipit |
Anthus rufulus |
0.03 |
0.28 |
LC |
IN |
|
|
Muscicapidae |
Black Redstart |
Phoenicurus ochruros |
0.23 |
2.22 |
LC |
IN |
|
|
|
Blue Whistling Thrush |
Myophonus caeruleus |
0.09 |
0.83 |
LC |
OM |
|
|
|
Bluethroat |
Luscinia svecica |
0.09 |
0.83 |
LC |
IN |
|
|
|
Grey Bush Chat |
Saxicola ferreus |
0.12 |
0.83 |
LC |
IN |
|
|
|
Indian Robin |
Copsychus fulicatus |
0.26 |
2.5 |
LC |
IN |
|
|
|
Oriental Magpie-Robin |
Copsychus saularis |
0.9 |
8.61 |
LC |
IN |
|
|
|
Pied Bush Chat |
Saxicola caprata |
0.52 |
5 |
LC |
IN |
|
|
|
Red-breasted Flycatcher |
Ficedula parva |
0.06 |
0.28 |
LC |
IN |
|
|
|
Siberian Stonechat |
Saxicola maurus |
0.12 |
1.11 |
LC |
IN |
|
|
|
White-rumped
Shama |
Copsychus malabaricus |
0.03 |
0.28 |
LC |
IN |
|
|
Nectariniidae |
Crimson Sunbird |
Aethopyga siparaja |
0.12 |
1.11 |
LC |
NC |
|
|
|
Purple Sunbird |
Cinnyris asiaticus |
1.71 |
12.22 |
LC |
NC |
|
|
Oriolidae |
Black-hooded Oriole |
Oriolus xanthornus |
0.87 |
7.5 |
LC |
OM |
|
|
|
Indian Golden Oriole |
Oriolus kundoo |
0.09 |
0.56 |
LC |
OM |
|
|
|
Maroon Oriole |
Oriolus traillii |
0.06 |
0.56 |
LC |
FR |
|
|
Paridae |
Cinereous Tit |
Parus cinereus |
0.93 |
8.06 |
LC |
IN |
|
|
Passeridae |
Yellow-throated Sparrow |
Gymnoris xanthocollis |
6.94 |
33.61 |
LC |
GR |
|
|
|
House Sparrow |
Passer domesticus |
0.06 |
0.28 |
LC |
OM |
|
|
Phylloscopidae |
Blyth's Leaf Warbler |
Phylloscopus reguloides |
0.03 |
0.28 |
LC |
IN |
|
|
|
Hume's Leaf Warbler |
Phylloscopus humei |
0.06 |
0.28 |
LC |
IN |
|
|
Pycnonotidae |
Black Bulbul |
Hypsipetes leucocephalus |
0.2 |
0.56 |
LC |
FR+IN |
|
|
|
Black-crested Bulbul |
Rubigula flaviventris |
0.17 |
1.11 |
LC |
FR+IN |
|
|
|
Himalayan Bulbul |
Pycnonotus leucogenys |
0.61 |
2.22 |
LC |
FR+IN |
|
|
|
Red-vented Bulbul |
Pycnonotus cafer |
2.17 |
9.17 |
LC |
OM |
|
|
|
Red-whiskered Bulbul |
Pycnonotus jocosus |
3.21 |
15 |
LC |
OM |
|
|
Sittidae |
Chestnut-bellied Nuthatch |
Sitta cinnamoventris |
0.2 |
1.39 |
LC |
IN |
|
|
|
Velvet-fronted Nuthatch |
Sitta frontalis |
0.06 |
0.56 |
LC |
IN |
|
|
Stenostiridae |
Grey-headed Canary-flycatcher |
Culicicapa ceylonensis |
0.12 |
1.11 |
LC |
IN |
|
|
Sturnidae |
Brahminy Starling |
Sturnia pagodarum |
0.84 |
3.33 |
LC |
OM |
|
|
|
Chestnut-tailed Starling |
Sturnia malabarica |
0.32 |
0.83 |
LC |
OM |
|
|
|
Common Myna |
Acridotheres tristis |
3.64 |
19.17 |
LC |
OM |
|
|
Turdidae |
Orange-headed Thrush |
Geokichla citrina |
0.06 |
0.56 |
LC |
IN |
|
|
Zosteropidae |
Indian White-eye |
Zosterops palpebrosus |
0.4 |
2.5 |
LC |
IN |
|
Pelecaniformes |
Threskiornithidae |
Red-naped
Ibis |
Pseudibis papillosa |
0.2 |
1.11 |
LC |
OM |
|
Piciformes |
Megalaimidae |
Brown-headed Barbet |
Psilopogon zeylanicus |
2.28 |
20 |
LC |
FR |
|
|
|
Coppersmith Barbet |
Psilopogon haemacephalus |
0.09 |
0.83 |
LC |
FR |
|
Piciformes |
Picidae |
Brown-capped Pygmy Woodpecker |
Yungipicus nanus |
0.14 |
1.11 |
LC |
IN |
|
|
|
Fulvous-breasted Woodpecker |
Dendrocopos macei |
0.09 |
0.83 |
LC |
IN |
|
|
|
Great Slaty
Woodpecker |
Mulleripicus pulverulentus |
0.38 |
1.67 |
VU |
IN |
|
|
|
Greater Flameback |
Chrysocolaptes guttacristatus |
0.17 |
1.39 |
LC |
IN |
|
|
|
Himalyan Flameback |
Dinopium shorii |
0.2 |
1.67 |
LC |
IN |
|
|
|
Black-rumped
Flameback |
Dinopium benghalense |
0.55 |
5 |
LC |
IN |
|
|
|
Rufous Woodpecker |
Micropternus brachyurus |
0.17 |
1.67 |
LC |
IN |
|
|
|
Streak-throated Woodpecker |
Picus xanthopygaeus |
0.35 |
3.33 |
LC |
IN |
|
|
|
White-naped
Woodpecker |
Chrysocolaptes festivus |
0.12 |
1.11 |
LC |
IN |
|
Psittaciformes |
Psittaculidae |
Plum-headed Parakeet |
Psittacula cyanocephala |
32.65 |
174.44 |
LC |
FR |
|
|
|
Rose-ringed Parakeet |
Alexandrinus Krameri |
8.39 |
42.22 |
LC |
FR |
|
|
|
Alexandrine Parakeet |
Palaeornis eupatria |
0.06 |
0.28 |
LC |
FR |
|
|
|
Red-breasted Parakeet |
Psittacula alexandri |
0.38 |
1.67 |
NT |
FR |
|
Unidentified |
Unidentified |
Unidentified |
|
0.06 |
0.28 |
|
|
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IMAGES - - CLICK HERE FOR FULL PDF
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