Density and Diversity of Water Birds and Terrestrial Birds at Paya Indah Wetland Reserve, Selangor Peninsular Malaysia
The main objectives of this study was to determine and compare the density and diversity of water birds and terrestrial birds using distance sampling point count method at Paya Indah Wetland Reserve, Selangor Peninsular Malaysia. A total of 13872 bird individuals from 100 bird species were recorded in the wetland reserve. Out of the total, 25 (22.26% of all detections) and 75 (77.74% of all detections) bird species belong to water birds and terrestrial birds respectively. The results showed that total bird density of the wetland reserve is 83.92±4.53 birds ha-1 and ranged from 75.40-93.41 birds ha-1 (95% confidence interval). The terrestrial birds have higher density (70.26±4.48 birds ha-1) as compared to water birds (13.09±1.78 birds ha-1). The highest water bird density was recorded for Purple Swamphen (5.05±0.89 birds ha-1) and the lowest was Ballion's Crake (0.31±0.13 birds ha-1). The highest terrestrial bird density was recorded for Yellow-vented Bulbul (12.97±1.05 birds ha-1) and the lowest was Ashy Minivet (0.31±0.18 birds ha-1). The highest species diversity i.e. Shannons index (N1 = 20.83), species richness i.e. Margalefs index (R1 = 7.97) and species evenness, i.e., McIntoshs index (E = 0.73) was recorded in terrestrial birds. This study indicated that Paya Indah Wetland Reserve is a highly important habitat and provides diverse food, shelter, nesting and roosting sites for water birds as well as terrestrial birds.
July 15, 2010; Accepted: October 18, 2010;
Published: November 12, 2010
Wetlands are widely recognized as highly important ecosystem with diverse attributes
including a distinctive avifauna (Burger, 1985). Freshwater
wetlands hold more than 40% bird species of the entire world and 12% of all
animal species (Kirsten and Brander, 2004). The gradual
losses of wetland habitats and degradation have caused declining of many bird
species (Taylor and Pollard, 2008). Many of them are
under heavy pressure and at risk due to degradation of breeding sites, water
level destabilization, sedimentation, contaminant and nutrient inputs and invasion
of exotic plants and animals (Scott and Poole, 1989).
Freshwater wetlands provide suitable breeding and foraging sites for more than
one quarter of the regional avifauna and most of them are nongame species (Naugle
et al., 2000). Various globally threatened and non-threatened bird
species depend on wetland to fulfil the daily requirements such as food, water
and shelter (Ishikawa et al., 2003). Wetland
birds are diverse and often show different behavioural tactics to explore the
wetland areas and reflect the ecological conditions of a particular area. Nevertheless,
the information on the population parameters and ecology of wetland birds is
scare (De Leon and Smith, 1999).
Malaysia is blessed with a total of 3.5 to 4.0 million ha of natural wetland
areas which is equal to 10% of the total land area (Aik,
2002). Malaysian wetlands are divided into ten major types namely mangroves,
mudflats, nipa swamps, freshwater swamp forest, peat swamp forest, lakes, river
systems (nearly 100 river systems), fresh marshes and wet rice paddy fields
(Malaysian Wetland Working Group, 1986). These wetland
areas serve as important habitats and refuges for wide array of migratory and
threatened bird species (Asmawi, 2007; Min,
To date no population study has been done to compare between waterbirds and terrestrial birds in freshwater wetland of Malaysia. Very little is known about the bird assemblages and population trends in freshwater wetland habitats. The main objective of this study was to determine and compare the density and diversity of waterbirds and terrestrial birds at Paya Indah Wetland Reserve, Selangor Peninsular Malaysia.
In this study the term water birds refers to bird species that entirely depend
on wetlands for variety of activities such as foraging, nesting, loafing and
moulting (Rajpar and Zakaria, 2009). Whereas the term
terrestrial birds refers to bird species that do not totally depends on the
wetland habitats but may use the wetland areas in search of food, shelter and
loaf. The species diversity is the number of different bird species in a particular
area while species density is a number of birds per unit area.
MATERIALS AND METHODS
Study site: Paya (swamp) Indah (beautiful) wetland reserve encompasses of 3050 ha out of which 450 ha are under the administration of the Department of Wildlife and National Parks, Peninsular Malaysia. The study area is located adjacent to Malaysia's administrative centre Putrajaya within the quadrant of 101° 10' to 101° 50' longitude and 2° 50' and 3° 00' latitude (Fig. 1).
Bird surveys: Bird surveys were carried out at Paya Indah Wetland Reserve,
Peninsular Malaysia using distance sampling point count method to determine
species composition, diversity and density within November 2007 to January 2009.
Sixty one point-count stations 300 m interval distance apart from each other
were established within the study area. The main reason of using 300 m interval
apart between point count stations was to avoid double counting of the same
birds at more than one station. The birds were surveyed fifteen consecutive
times at monthly interval for each station to obtain reliable estimates and
to reduce bias. The replication of point count stations increased precision
and provide reliable results (Petit et al., 1995;
Smith et al., 1993).
The survey was done early in the morning from 0730 and 1100 h. The detections
of birds within each point count station were done for ten-minutes.
|| Location map of paya indah wetland reserve, selangor peninsular
Ten-minute count enables to record sufficient number of individuals with minimal
efforts and disturbance (Lee and Marsden, 2008; Jimenez,
2000; Lynch, 1995; Gutzwiller,
1991). During each survey all bird species and individuals seen or heard
and the distance from the point station to the birds were estimated. The flushed
birds with known original position were included in the analysis while flying
birds were omitted due to unknown original position. The methodology was followed
as described by Nadeau et al. (2008), Aborn
(2007), Buckland et al. (2004) and Bibby
et al. (2000).
Data analysis: The density of bird species was determined using Distance
Software (Version 4.1) by Buckland et al. (2004).
The bird density of those species whose numbers of detections were below five
were not analyzed due to low number of sample size. The methodology was followed
as described by Marsden (1999). The diversity indices
such as species diversity, richness and evenness were determined using Community
Analysis Package Software (CAP, Version 4.0) by Henderson
and Seaby (2007).
Species composition: Distance sampling point count method detected a
total 13872 bird individuals that belong to 100 species and 38 families at Paya
Indah Wetland Reserve, Selangor Peninsular Malaysia. Out of the total number
of species, 25 bird species were belongs to water birds (3088 detections; 22.26%)
and 75 bird species were belongs to terrestrial birds (10784 detections; 77.74%)
(Appendix 1 and 2).
Overall bird density: The density analysis shows that the bird density of Paya Indah Wetland Reserve, Peninsular Malaysia is 83.92±4.53 birds ha-1 that ranged from 75.40-93.41 birds ha-1 (95% confidence interval). The results also show that the terrestrial birds have higher density (70.26±4.48 birds ha-1) as compared to water birds (13.09±1.78 birds ha-1) (Table 1).
Water bird density: The five highest waterbird species density was recorded for Purple Swamphen (5.05±0.89 birds ha-1) followed by Lesser Whistling Duck (4.66±1.12 birds ha-1), White-breasted Waterhen (3.02±0.35 birds ha-1), Yellow Bittern (2.84±0.62 birds ha-1) and Cotton Pygmy Goose (2.63±0.11 birds ha-1). The five lowest waterbird density was recorded for Little Grebe (0.35±0.12 birds ha-1), Black-crowned Nightheron (0.33±0.12 birds ha-1), Ballion's Crake (0.31±0.13 birds ha-1), Pheasant-tailed Jacana (0.26±0.12 birds ha-1 and Grey Heron (0.13±0.05 birds ha-1). In addition, the densities of four water birds namely Common Kingfisher; A. atthis, Great Egret; C. albus, Little Egret; E. garzetta and Slaty-breasted Crake; G. striatus were not analyzed due to very low detections (< 5 observations) (Table 2).
|| The density of water birds and terrestrial birds of paya
indah wetland reserve, peninsular Malaysia
|| Ranking of water bird density at paya indah wetland reserve,
||Ranking of terrestrial bird density at paya indah wetland
reserve, selangor peninsular Malaysia
Terrestrial bird density: The five highest terrestrial bird density
was recorded for Yellow-vented Bulbul (12.97±1.05 birds ha-1)
followed by Pink-necked Green Pigeon (11.4±1.15 birds ha-1),
Peaceful Dove (9.85±0.96 birds ha-1), Eurasian Tree Sparrow
(7.85±2.17 birds ha-1) and Rufous-tailed Tailorbird (7.54±1.43
||Comparison of bird species diversity of terrestrial birds
and water birds at paya indah wetland reserve, selangor peninsular Malaysia
The five lowest terrestrial bird density was recorded for Black-throated Sunbird
(0.41±0.19 birds ha-1) followed by Rufous Woodpecker (0.40±0.14
birds ha-1), Greater Coucal (0.39±0.15 birds ha-1),
Little Spiderhunter (0.34±0.12 birds ha-1) and Ashy Minivet
(0.31±0.18 birds ha-1). In addition, eighteen bird species
were not analyzed due to small sample size (<5 observations) (Table
Diversity: Diversity is a major aspect of species structure in avian
community. Principal Component Analysis Software (CAP Version 4.0) by Henderson
and Seaby (2007) was used to determine and compare the diversity of water
birds and terrestrial birds in the study area. The result shows that terrestrial
birds have the highest species diversity i.e., Shannons index (N1
= 20.83), species richness i.e., Margalefs index (R1
= 7.97) and species evenness i.e., McIntoshs index (E = 0.73) was recorded
in terrestrial birds compared to water birds (Table 4).
Freshwater wetlands are highly important habitat for wide array of waterbirds as well as terrestrial birds and their importance depends on size, diversity of vegetation, water quality, food resources and topography. Birds are most conspicuous and significant component of freshwater wetland ecosystems and their presence or absence may indicate the ecological conditions of the particular areas.
The growing pressure on wetland resources due to human activities, climatic
and edaphic changes has caused great threats to wetland fauna especially water
birds throughout the world (Greenwood et al., 1995;
Laurance, 1999). Determining the accurate population
size and population fluctuation of different birds in wetland habitats is highly
important to understand the bird community structures and population status
of existing species in the dwelling area (Thompson, 2002;
De Sante et al., 2005; Kaminski
et al., 2006).
Paya Indah Wetland Reserve is a natural wetland and extremely variable in vegetation structures, vegetation composition and productivity (food resources, nesting sites and shelter). The recording of 25 water bird species and 75 terrestrial bird species using point count method shows that this wetland reserve is a highly important habitat and support diverse water birds and terrestrial birds in order to perform multiple activities such as foraging, breeding, loafing and roosting. The occurrence of higher number of species could be due to vegetation diversity such as trees, shrubs, emergent and submerged vegetation, reeds and sedges, ferns, grasses and herbs that provides multiple microhabitats. The different strata of vegetations also have attracted different bird species through offering optimal combinations of food, water and shelter resources that satisfy the daily requirements of bird species to maintain their populations.
The results of this study show that the highest water bird density was recorded
in Purple Swamphen followed by Lesser Whistling Duck and White-breasted Waterhen.
This may be due to diversity and richness of aquatic vegetation such as emergent
vegetation (i.e. Eleocharis dulcis, Nelumbo nucifera, Nelumbo
pubescens and Philydrum lanuginosum), grasses (i.e., Scirpus olneyi,
Panicum maximum and Imperata cylindrical), sedges and rush (i.e.,
Scleria purpurascens and Spartina alterniflora), ferns (i.e.,
Stenochlaena palustris, Cyclosorus interruptus and Lycopodium cernuum),
reeds (i.e., Phragmites karaka and Typha angustifolia), submerged
(Myriophyllum spicatum, Salvinia minima, Creatophyllum demersum
and Elodea sp.) and herbaceous plants (i.e., Cyperus sp.,
Junicus effuses and Panicum repens) that created suitable habitats
and offer abundant food resources, safe breeding sites and hiding cover from
predators and weather. Heterogeneity of aquatic vegetation also provides a dwelling
area for different invertebrate assemblages such as Oligochaeta, Turbellaria,
Hirudinidea, Pelecypoda, Arachnida, Insecta and Crustacea (Kostecke
et al., 2005). These invertebrates are an important food sources
for waterbirds (Anderson and Smith, 2000). The greater
abundance of invertebrate are closely related to dense aquatic vegetation due
to higher habitat structural complexity (Gray et al.,
1999; De Szalay and Resh, 2000).
Water birds are closely associated to wetland aquatic vegetation to complete
their life cycles and often select the most available microhabitats in different
ways depending on their behaviour or spatial location (Nudds
et al., 1994; Green, 1998; Hag
et al., 1998). Vegetation composition and structure (Isacch
et al., 2005), habitats characteristics and food resources (Murkin
et al., 1997; Farmer and Wiens, 1999; Ashley
et al., 2000) and surrounding landscape are the key factors that
influence the distribution, diversity, density and habitat selection of bird
species (Pearson, 1993; Koopowitz
et al., 1994; Vos and Stumpel, 1995).
Factors that influence the habitat selection may vary from species to species.
For example; species morphology, foraging behaviour (e.g., visual vs. tactile
foragers) and prey availability (i.e., prey density and vulnerability to capture)
may affect the distribution and reproduction success of water birds (Gawlik,
2002). Hattori and Mae (2001) stated that the highest
species richness and density of water birds occurs in reed bed of aquatic vegetation
where the water level is 20 to 65 cm in depth. Fairbairn
and Dinsmore (2001) and Kushlan (2000) also reported
that water bird density is associated with habitat variables such as vegetation
cover, food, safe nursing and loafing sites. This study indicated that waterbird
populations are directly influenced by the amount and quality of available foraging
habitats and they select wetland areas with surface water that supply suitable
prey organisms for foraging.
The highest terrestrial bird density was recorded in Yellow-vented Bulbul followed
by Pink-necked Green Pigeon, Peaceful Dove, Eurasian Tree Sparrow, Scaly-breasted
Munia and Baya Weaver. This could be due to the presence of different habitats
such as marsh swamp, lotus swamp, open water body, dryland and patches of shrubs
and availability of abundant food sources such as variety of fruits, insects,
seeds, grains, safe roosting and breeding sites. These similar observations
have been recorded by Zakaria et al. (2009) and
Rajpar and Zakaria (2009). The distribution of scatered
trees and patches of shrubs created different layers of vegetation that serve
as potential foraging and nesting sites for them. Vertical layering and complexity
of vegetation has increased the foraging surfaces for terrestrial insectivore
and frugivore bird species. The adjacent areas such as oil palm plantation and
forest reserve may also influence the distribution of bird species. Petit
and Petit (1996) and Cody (1985) reported that bird
density is positively correlated with habitat heterogeneity and preference.
The results of diversity analysis show that bird species diversity may vary
from terrestrial birds to water birds. The higher bird diversity, richness and
evenness were recorded in terrestrial birds as compared to water birds. This
may be due to difference in habitat richness and diversity of vegetation such
as trees, shrubs, emergent vegetation, grasses, sedges, rushes, ferns, reeds,
submerged and herbaceous plants. The terrestrial birds seem to be capable of
using all available habitats within the wetland area. Unlike the water birds
which are highly dependent on the water based or water related habitats such
as marsh swamp, lotus swamp and open water body. In most instances, bird diversity
is parallel to habitat diversity as suggested by Buffington
et al. (1997) and Jobin et al. (2001)
In addition, other factors such as weather (rainfall), social interactions
and predators such as Water Monitor Lizard (Varanus salvator), Monitor
Lizard (Varanus begalensis), Python (Python reticulates), King
Cobra (Ophiophagus hannah), Cobra (Naja naja) may also affect
the distribution and habitat selection of water as well as terrestrial birds
in the wetland reserve. These findings were consistent with other studies in
similar types of habitat (Zakaria et al., 2009).
This study indicated that Paya Indah Wetland Reserve is highly important habitat for waterbirds as well as terrestrial birds. The wetland bird richness is closely associated with vegetation structure and composition, size of wetland, diversity and abundance of food resources and shallowness of water. Habitat structural diversity provides refuge from predators.
The authors would like to thank Department of Wildlife and National Parks, Peninsular Malaysia to allow conducting this research study at Paya Indah Wetland Reserve. This research was partially funded by Fundamental Grant Research Scheme 01-10-07-291FR and Forestry Sector Research Division Project, Pakistan Forest Institute, Peshawar Pakistan.
||List of water bird species recorded using point count method
at paya indah wetland reserve, peninsular Malaysia
||List of terrestrial bird species recorded using point count
method at paya indah wetland reserve, peninsular Malaysia
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