Journal of
Threatened Taxa | www.threatenedtaxa.org | 26 May 2018 | 10(6):
11725–11731
Species diversity and abundance of birds on Bharathiar
University Campus, Tamil Nadu, India
L. Arul Pragasan
1 & M. Madesh 2
1,2 Environmental Ecology Laboratory,
Department of Environmental Sciences, Bharathiar
University, Coimbatore, Tamil Nadu 641046, India
1arulpragasan@yahoo.co.in (corresponding
author), 2msschitty@gmail.com
Abstract: University campuses play a significant
role in the conservation of avifaunal diversity, but there are very few studies
on birds of such local biodiversity hotspots in India. Here, we document the patterns of abundance
and species diversity of birds in Bharathiar
University campus located in western Tamil Nadu, India. Birds were sampled using point
counts. A total of 37 species
belonging to 23 families were recorded from 144 point
count samples. Mean species
richness per point count sample was 13.85±0.47 species (±SD), and Shannon
diversity index (Hʹ) was 0.74.
This study provides baseline data for monitoring the avifauna in the
university campus, and demonstrates the importance of university campuses in
bird conservation.
Keywords: Birds, India, point counts, Shannon
diversity, University campus.
doi: http://doi.org/10.11609/jott.2965.10.6.11725-11731 | ZooBank:
urn:lsid:zoobank.org:pub:7DA3637F-A7FA-4F71-8595-37F9981E845B
Editor: R. Jayapal, SACON, Coimbatore, India. Date
of publication: 26 May 2018 (online & print)
Manuscript details: Ms # 2965 |
Received 10 January 2017 | Final received 05 April 2018 | Finally accepted 23
April 2018
Citation: Pragasan, L.A. & M. Madesh (2018). Species diversity and
abundance of birds on Bharathiar University Campus,
Tamil Nadu, India. Journal of Threatened
Taxa 10(6): 11725–11731; http://doi.org/10.11609/jott.2965.10.6.11725-11731
Copyright: © Pragasan & Madesh
2018. Creative Commons Attribution 4.0
International 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: None.
Competing interests: The authors declare no competing interests.
Author Details: L. Arul Pragasan is serving as an Assistant Professor in the Department of Environmental
Sciences, Bharathiar University since March 2011. His
area of research is on environmental ecology, particularly on biodiversity
conservation, functional ecology, carbon stock assessment, experimental
research on climate change impacts. He is guiding PhD, MPhil and MSc students for their reseach projects.
M. Madesh
is a MPhil student, has succussfully
completed MPhil in Environmental Sciences, and currently looking for research
position in a reputed institution. His area of research interest is on
avifaunal ecology.
Author Contribution: LAP - designing of research work, data analysis, and paper writing. MM -
field work and data collection.
Acknowledgements:
Authors sincerely thank Bharathiar
University for the support of this research work.
Introduction
The
combined effect of climate change (Opdam & Wascher 2004; Knudsen et al. 2011) and urbanization
(McKinney 2006; Paton et al. 2012; Tscharntke et al.
2012; Ferenc et al. 2014; Rayner
et al. 2015) leading to habitat loss remains one of the most challenging issues
for conservation of bird diversity.
Under this situation, remnants of wild vegetation and plantations in
walled university campuses provide a hope for bird conservation. In India, there are 744 universities
with varying land size, and most of them have at least a few patches of natural
vegetation and plantations. Documentation of birds in such areas,
however, was not given importance on par with forests and other reserve
areas. Bharathiar
University (BU) in western Tamil Nadu with c.1000 acres of land area in
tropical climatic zone is one among the last citadels of biodiversity in an
increasingly urbanized landscape.
An attempt was made in the present study to achieve the following main
objectives: (1) to determine species diversity, frequency, abundance and
importance value index of birds on BU campus, and (2) to study the patterns of
dominance among the birds of BU.
MATERIALS AND
METHODS
Study Area
The
present study was carried out on BU campus located in Coimbatore, Tamil Nadu, India (Fig. 1).
It covers ca. 1,000 acres and lies between 11.031–11.0470N
& 76.869–76.8700E at tropical climatic zone. The terrain of the campus is almost
plain, and the elevation gradually varies from 482–512 m. The campus is predominantly covered with
non-calcareous sandy loam red soil, with low organic carbon. It has a few remnants of wild vegetation
and plantation forests of about 25 years old.
The
available climate data (Karthick & Pragasan 2014) for the study area (for the period
2002–2011) revealed that the average annual rainfall was 645mm, and the
rainfall was maximum (54% of the total rainfall)
during October–November (Fig. 2).
Mean monthly temperature for the same period was 270C (Fig.
3). The mean minimum and maximum
temperatures were 220C and 320C, respectively.
Methods
Abundance
of birds in BU campus was estimated using point counts survey method (Bibby et al. 1992; Horak et al.
2013). In the present study, point
count stations were established at every 100m distance along a 500-m line
transect, and at each survey point 10 minutes were spent counting birds (Jiguet et al. 2012) within a radius of 50m. A total of 144 point
counts were done in 97 non-rainy days from February 2014 to July 2014. Samples were carried out soon after
sunrise in the morning (06:00–08:00 hr) or
before sunset in the evening (16:00–18:00 hr). Birds were identified
using the field guide by Ali (2012). The IUCN Red List of Threatened Species
was followed for nomenclature and taxonomy.
Species
richness was calculated as the total number of bird species
recorded from the 144 point count samples. Abundance and frequency were
calculated for all the bird species recorded in this study. Abundance was determined as the total
number of bird counts, and frequency was determined as the total number of
occurrence of birds in each sample (n=144).
Diversity
of birds in the university campus was determined using Shannon diversity index
(HÕ) following Magurran (2004), HÕ = - ·pi
× ln pi, where, pi
is the proportion of the total number of individuals of species ÔiÕ. Chao 2, a
non-parametric estimator of species richness which uses occurrence data from
multiple samples in aggregate to estimate the species diversity of the whole,
was determined using Biodiversity Pro (version 2). The observed species richness was compared
with expected species richness (Chao 2) using species-sample curve, as number
of samples on x-axis against cumulative number of species on y-axis.
Modified
important value index (IVI), a measure of relative prominence of various
species was calculated for all the species to find the key species in the
university campus following Suripto et al. (2015),
IVI = rF + rA, where rF is relative frequency of the species; rA is relative abundance of the species.
Based
on abundance all the birds recorded were classified into four dominant/rare
categories, viz., predominant (birds with >1000 counts), dominant
(500–1000 counts), rare (100–500 counts) and very rare (<100
counts).
RESULTS
A total
of 37 bird species belonging to 23 families were recorded from 16,689 bird
sightings in 144 point counts bird survey samples
(Table 1). The density of birds
recorded per sample was 115.90±56.89 birds (± S.D.), this high value can be
attributed to large flocks of birds in movement, and it ranged from just one to
313 birds per sample. The mean species richness (number of bird species) per
sample was 13.85±5.58 species, and species richness ranged from one to 26
species per sample. Shannon
diversity index calculated for BU campus was 0.74. The observed and expected (Chao 2)
species richness for the present study had almost a similar trend (Fig.
4). The frequency (n=144) of bird
occurrence was maximum for Indian Peafowl with 97,
followed by Common Myna (96), Rufous
Treepie (95), Western Koel
(94) and Large-billed Crow, House Crow and Purple Sunbird had 93 each (Table
2). Total abundance was greater for
House Crow (3,237), followed by Indian Peafowl (2,512), Common Myna (2,191), Yellow-billed Babbler (1,947) and Cattle
Egret (851) (Table 2). House crow
scored maximum IVI value 24.06, followed by Indian Peafowl (19.92), Common Myna (17.94), Yellow-billed Babbler (16.28) and Cattle
Egret (9.06) (Table 2).
Among
the four dominant/rare categories, the predominant
category alone contributed a maximum (59%) to total abundance but had just 11%
of total species richness (Fig. 5).
In contrast, the very rare category with almost twenty times lesser than
the contribution of predominant category in total abundance, shared 43% of the
total species richness. Birds such
as House Crow, Indian Peafowl, Common Myna and
Yellow-billed Babbler with high abundance fell under the predominant category
(Table 2). According to IUCN Red
List, all the species recorded in the present study come under Least Concern
category.
Table 1. List of birds recorded from the
Bharathiar University Campus located in Tamil Nadu
Order/Family |
Species Name (with Authority) |
Common Name |
Category |
Pelecaniformes |
|||
Ardeidae |
Bubulcus ibis (Linnaeus, 1758) |
Cattle Egret |
D |
Accipitriformes |
|||
Accipitridae |
Milvus migrans (Boddaert,
1783) |
Black Kite |
VR |
Galliformes |
|||
Phasianidae |
Francolinus pondicerianus (Gmelin,
1789) |
Grey Francolin |
D |
|
Pavo cristatus Linnaeus, 1758 |
Indian Peafowl |
PD |
Columbiformes |
|||
Columbidae |
Chalcophaps indica (Linnaeus, 1758) |
Emerald Dove |
VR |
|
Columba livia Gmelin,
1789 |
Rock Dove |
D |
|
Streptopelia chinensis chinensis (Scopoli, 1786) |
Spotted Dove |
VR |
Psittaciformes |
|||
Psittacidae |
Psittacula krameri (Scopoli,
1769) |
Rose-ringed Parakeet |
VR |
Cuculiformes |
|||
Cuculidae |
Centropus sinensis (Stephens, 1815) |
Greater Coucal |
R |
|
Eudynamys scolopaceus (Linnaeus, 1758) |
Western Koel |
R |
Strigiformes |
|||
Strigidae |
Athene brama (Temminck,
1821) |
Spotted Owlet |
R |
Caprimulgiformes |
|||
Apodidae |
Cypsiurus balasiensis (Gray,
1829) |
Asian Palm-swift |
R |
Coraciiformes |
|||
Alcedinidae |
Halcyon smyrnensis (Linnaeus, 1758) |
White-breasted Kingfisher |
VR |
Meropidae |
Merops orientalis Latham, 1802 |
Asian Green Bee-eater |
R |
Piciformes |
|||
Megalaimidae |
Psilopogon haemacephalus (MŸller, 1776) |
Coppersmith Barbet |
R |
Picidae |
Dinopium benghalense (Linnaeus, 1758) |
Black-rumped Flameback |
VR |
|
Dinopium javanense (Ljungh,
1797) |
Common Flameback |
VR |
Passeriformes |
|||
Campephagidae |
Pericrocotus flammeus (Forster, 1781) |
Scarlet Minivet |
VR |
Cisticolidae |
Orthotomus sutorius (Pennant, 1769) |
Common Tailorbird |
R |
Corvidae |
Corvus macrorhynchos Wagler,
1827 |
Large-billed Crow |
D |
|
Corvus splendens Vieillot,
1817 |
House Crow |
PD |
|
Dendrocitta vagabunda (Latham, 1790) |
Rufous Treepie |
R |
Dicruridae |
Dicrurus caerulescens (Linnaeus, 1758) |
White-bellied Drongo |
VR |
Dicruridae |
Dicrurus macrocercus Vieillot,
1817 |
Black Drongo |
R |
Motacillidae |
Dendronanthus indicus (Gmelin,
1789) |
Forest Wagtail |
VR |
|
Motacilla maderaspatensis Gmelin,
1789 |
White-browed Wagtail |
VR |
Cisticolidae |
Prinia socialis Sykes, 1832 |
Ashy Prinia |
R |
Leiotrichidae |
Turdoides affinis (Jerdon,
1845) |
Yellow-billed Babbler |
PD |
Monarchidae |
Terpsiphone paradisi (Linnaeus, 1758) |
Indian Paradise-flycatcher |
VR |
Nectariniidae |
Cinnyris asiaticus (Latham, 1790) |
Purple Sunbird |
R |
|
Cinnyris lotenius (Linnaeus, 1766) |
Loten's Sunbird |
R |
|
Leptocoma zeylonica (Linnaeus, 1766) |
Purple-rumped
Sunbird |
R |
Passeridae |
Gymnoris xanthocollis (Burton, 1838) |
Yellow-throated Sparrow |
VR |
|
Passer domesticus (Linnaeus, 1758) |
House sparrow |
VR |
Pycnonotidae |
Pycnonotus cafer (Linnaeus, 1766) |
Red-vented Bulbul |
VR |
|
Pycnonotus jocosus (Linnaeus, 1758) |
Red-whiskered Bulbul |
VR |
Sturnidae |
Acridotheres tristis (Linnaeus, 1766) |
Common Myna |
PD |
(Category (dominant/rare category); VR - very rare; R
- rare; D - dominant; PD - predominant)
Table 2. Frequency, abundance and IVI
value of the 37 bird species recorded
Species Name |
Frequency (n=144) |
Abundance |
IVI |
||
Total |
Mean |
±SD |
|||
Corvus splendens Vieillot,
1817 |
93 |
3237 |
22.48 |
18.15 |
24.06 |
Pavo cristatus Linnaeus, 1758 |
97 |
2512 |
17.44 |
13.65 |
19.92 |
Acridotheres tristis (Linnaeus, 1766) |
96 |
2191 |
15.22 |
12.27 |
17.94 |
Turdoides affinis (Jerdon,
1845) |
92 |
1947 |
13.52 |
11.81 |
16.28 |
Bubulcus ibis (Linnaeus, 1758) |
79 |
851 |
5.91 |
9.38 |
9.06 |
Corvus macrorhynchos Wagler,
1827 |
93 |
684 |
4.75 |
5.05 |
8.76 |
Francolinus pondicerianus (Gmelin,
1789) |
79 |
635 |
4.41 |
5.17 |
7.77 |
Columba livia Gmelin,
1789 |
77 |
641 |
4.45 |
5.17 |
7.70 |
Eudynamys scolopaceus (Linnaeus, 1758) |
94 |
426 |
2.96 |
2.74 |
7.27 |
Dendrocitta vagabunda (Latham, 1790) |
95 |
398 |
2.76 |
3.30 |
7.15 |
Cinnyris asiaticus (Latham, 1790) |
93 |
387 |
2.69 |
2.60 |
6.98 |
Dicrurus macrocercus Vieillot,
1817 |
91 |
353 |
2.45 |
2.51 |
6.68 |
Orthotomus sutorius (Pennant, 1769) |
83 |
328 |
2.28 |
3.34 |
6.13 |
Centropus sinensis (Stephens, 1815) |
90 |
219 |
1.52 |
1.71 |
5.83 |
Psilopogon haemacephalus (MŸller, 1776) |
76 |
235 |
1.63 |
2.18 |
5.22 |
Leptocoma zeylonica (Linnaeus, 1766) |
63 |
243 |
1.69 |
2.78 |
4.62 |
Cinnyris lotenius (Linnaeus, 1766) |
63 |
238 |
1.65 |
2.11 |
4.59 |
Merops orientalis Latham, 1802 |
66 |
186 |
1.29 |
1.67 |
4.42 |
Athene brama (Temminck,
1821) |
60 |
165 |
1.15 |
1.79 |
4.00 |
Halcyon smyrnensis (Linnaeus, 1758) |
64 |
86 |
0.60 |
1.15 |
3.72 |
Prinia socialis Sykes, 1832 |
50 |
133 |
0.92 |
1.42 |
3.30 |
Cypsiurus balasiensis (Gray,
1829) |
34 |
170 |
1.18 |
2.42 |
2.72 |
Motacilla maderaspatensis Gmelin,
1789 |
30 |
32 |
0.22 |
0.45 |
1.70 |
Pericrocotus flammeus (Forster, 1781) |
26 |
51 |
0.35 |
0.83 |
1.61 |
Pycnonotus cafer (Linnaeus, 1766) |
24 |
36 |
0.25 |
0.99 |
1.42 |
Streptopelia chinensis chinensis (Scopoli, 1786) |
25 |
26 |
0.18 |
0.40 |
1.41 |
Dendronanthus indicus (Gmelin,
1789) |
22 |
24 |
0.17 |
0.41 |
1.25 |
Dinopium benghalense (Linnaeus, 1758) |
21 |
28 |
0.19 |
0.53 |
1.22 |
Gymnoris xanthocollis (Burton, 1838) |
17 |
32 |
0.22 |
0.75 |
1.04 |
Pycnonotus jocosus (Linnaeus, 1758) |
18 |
19 |
0.13 |
0.36 |
1.02 |
Passer domesticus (Linnaeus, 1758) |
10 |
61 |
0.42 |
2.84 |
0.87 |
Milvus migrans (Boddaert,
1783) |
15 |
17 |
0.12 |
0.36 |
0.85 |
Dicrurus caerulescens (Linnaeus, 1758) |
13 |
29 |
0.20 |
0.78 |
0.83 |
Psittacula krameri (Scopoli,
1769) |
12 |
26 |
0.18 |
0.65 |
0.76 |
Dinopium javanense (Ljungh,
1797) |
13 |
14 |
0.10 |
0.32 |
0.74 |
Terpsiphone paradisi (Linnaeus, 1758) |
10 |
18 |
0.13 |
0.55 |
0.61 |
Chalcophaps indica (Linnaeus, 1758) |
10 |
11 |
0.08 |
0.29 |
0.57 |
(D/R Cat.- dominant/rare
category; VR- very rare; R-rare; D-dominant; PD-predominant)
DISCUSSION
Birds
are used for assessing ecosystem quality (Ridley et al. 1984). To have effective conservation measures
in place, it is necessary to study the population size of birds. Population studies were, for long, used
to monitor long time changes in natural and manmade ecosystems (Wiens 2001).
The study area, Bharathiar University campus
with a few patchy remnants of wild vegetation, plantation, garden, avenue
plants and lawn, structurally provides a complex landscape that supports a fair
diversity of bird species. Empirical
and theoretical evidence have proved that local species richness is highly
influenced by the landscape and regional species pools (Lawton 1999; Gaston
2000), and structurally complex landscapes support more species than simple
landscapes.
When
compared, the species richness of the present study (37 species) is almost
fifty per cent lesser than the value (73 species) reported for Assam University
campus located in Silchar, India (Chakdar
et al. 2016). Shannon diversity
index recorded for the present study (0.74) is lesser than the evergreen
forests of Silent Valley (3.3) and moist deciduous forests of Mukkali (3.45) (Jayson & Mathew 2000), both located
around 60 km away from the present study area.
It is
important to study the diversity of avifauna in the university campus to help
to monitor and conserve the biological diversity of the region where buildings
are increasing in numbers replacing the green vegetation and agricultural lands
that support avifauna. In the
present study, the maximum species (37 species) was achieved at the 35th
point count sample (one-fourth of the total sample size) indicating the
sampling adequacy. When compared,
the observed species richness and the expected (Chao2) species richness were
almost similar in terms of cumulative species richness (Fig. 4). The total abundance was recorded greater
for House Crow as expected, and it was followed by Indian
Peafowl, Common Myna, Yellow-billed Babbler and
Cattle Egret (Table 2).
While, the frequency of bird occurrence was maximum observed for Indian
peafowl (4.9%) indicating that the national bird occupies all nook and corners
of the campus, and it was surprising to observe such a big bird scored high
against the most abundant House Crow.
In fact, the latter scored less than Common Myna,
Rufous Treepie and Western Koel, and scored the same as Large-billed Crow and Purple
Sunbird (Table 2).
Categorizing
birds into dominant/rare category helps to understand the structure of a bird
population. In the present study,
although there are 37 species, about 43% of them belong to very rare category
(<100 bird counts). This
explains the bird population structure of the campus. Though, all the species of the campus
come under Least Concern category according to the IUCN Red List, there is a pressing
need for prompt steps to conserve bird populations in the campus. To maintain a
viable population, conservation measures are needed. There are several factors that influence
changes in bird populations such as availability of food, location of nesting
sites, availability of nesting materials, introduced diseases, introduced and
invasive flora, predators, and competitors (Margules
et al. 2000; Ramesh & McGowan 2009), however, habitat loss is considered
atop among the others. At this
stage, educational institutions like BU with natural and plantation forests
serve as a good habitat for the bird community.
CONCLUSION
Bharathiar University campus supports a fair diversity of birds. The present study provides baseline data
for monitoring bird diversity in the campus. This study creates awareness on
documenting birds in other university campuses in the nation. Future research on the behavior and feeding ecology of birds in the campus will
help to understand birds more accurately and thereby pave the way for better
conservation measures. Birds play
ecologically significant role in plant pollination and seed dispersal, and
their conservation is highly necessary for the proper functioning of the
ecological system. Although there
are natural and plantation forests in the BU campus as habitat for birds of
this region, conservation measures are of immense need for their future
survival. We suggest following
conservation measures for protecting the diversity of birds in the university
campus: (1) awareness program for conservation of bird species among the campus
aspirants, and (2) initiating biomonitoring program
is necessary for monitoring and conservation of the birds of BU campus.
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