Journal of Threatened Taxa |
www.threatenedtaxa.org | 26 September 2022 | 14(9): 21786–21796
ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print)
https://doi.org/10.11609/jott.7816.14.9.21786-21796
#7816 | Received 04 January 2022 | Final received 01 July
2022 | Finally accepted 24 August 2022
Population
density and nesting behaviour of Indian Giant
Squirrel Ratufa indica (Erxlebeln, 1777) in Bhimashankar
Wildlife Sanctuary, Western Ghats of Maharashtra, India
Ganesh
Rathod 1 , Erach
Bharucha 2 & Kranti Yardi 3
1,2,3
Bharati Vidyapeeth Institute of Environment Education
and Research, Bharati Vidyapeeth Deemed to Be University, Dhankawadi,
Pune, Maharashtra 411043, India.
1 ganeshrathod8757@gmail.com (corresponding author),
2 erach.bharucha@bharatividyapeeth.edu, 3 kranti.yardi@bharatividyapeeth.edu
Abstract:
The Indian Giant Squirrel Ratufa indica
(Erxlebeln, 1777) has been officially designated as
Maharashtra’s state animal. It is restricted to the eco-sensitive Western Ghats
region and is currently classified as Least Concern species on the IUCN Red
List. However, the species is dependent on intact habitat and is negatively
impacted by habitat fragmentation. Population density and nesting behavior were
studied in a major habitat in the tropical semi-evergreen and evergreen forest
of India’s Bhimashankar Wildlife Sanctuary.
Two-hundred-and-twenty-three direct sighting along 60 km line transects were
used to estimate squirrel density. It averaged 13.9±0.18 squirrels/km2.
Nesting characteristics were evaluated using 4,224 nests. The squirrel uses 52
different tree species for nesting, with Mangifera indica (15.57%), Olea
dioica (14.65%), and Mallotus phillippensis (9.78%) being the most popular. The drays
were found on trees that are taller than average, have a massive girth at the
breast height, and have continuous closed canopies. To avoid predators, Indian
Giant Squirrels usually flee to the nearest adjacent tree.
Keywords:
Cryptic behaviour, drey, population density, rodent, Rodentia, sacred grove,
Sciuridae.
Editor:
Giovanni Amori, CNR-Research Institute on
Terrestrial Ecosystems, Rome, Italy. Date of publication: 26 September 2022 (online
& print)
Citation:
Rathod, G., E. Bharucha & K. Yardi (2022).
Population density and nesting behaviour of Indian
Giant Squirrel Ratufa indica (Erxlebeln, 1777) in Bhimashankar
Wildlife Sanctuary, Western Ghats of Maharashtra, India.
Journal of Threatened Taxa 14(9): 21786–21796.
https://doi.org/10.11609/jott.7816.14.9.21786-21796
Copyright:
© Rathod et al. 2022. 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: Self-funded.
Competing interests: The authors
declare no competing interests.
Author details: Mr. Ganesh Rathod is a field biologist who has a master’s degree in
Wildlife Conservation and Action and work with The Corbett Foundation in
Maharashtra. Dr. Erach Bharucha
is a surgeon by profession and a biodiversity and landscape conservation expert
by passion. He has been active in the fields of wildlife and nature
conservation over the past five decades. He has studied the Indian national
parks, wildlife sanctuaries, and tribal cultures of India extensively. He was
also the first Chairman of the Maharashtra State Biodiversity Board. Dr. Kranti
Yardi is a professor and expertise in conservation biology, natural
resource management, bat ecology, impact assessment, environmental education.
She served as chairperson of the Maharashtra State Textbook Bureau’s
Environment Science textbook committee for grades XI and XII. Member, Bharati
Vidyapeeth Board of Studies in Environment Science (Deemed to be University).
Author contributions: GR—Identification
of Indian giant squirrels nesting sites, designing and finalizing of the techniques
(methodology), field surveys and data collection, data analysis, data
interpretation, and revision of the paper. EB—Conceptualization of study,
guiding at every step and discussions periodically regarding the data
collection. Writing the manuscript and correcting at every stage till it is
finalised. KY—Finalization of topic, providing all necessary help for
permissions, time to time discussion and submission of work.
Acknowledgments:
The authors are thankful to the R.K. Wankhede (IFS),
conservator of forests (wildlife) Pune, Bhimashankar
Wildlife Division, and all forest staff for their help during the study.
Introduction
The Indian Giant Squirrel Ratufa
indica is the world’s largest tree squirrel and can be found in a
variety of forest habitats (Borges et al. 2008). It is most common in
continuous forest canopies. Its large body size and intense vocalisations
limit it to arboreal niches. It does, however, require continuous canopies to
move through its territories. It is frugivorous and granivorous, making it an
excellent natural pollinator. It constructs a globular nest out of leaves and
twigs (Borges et al. 1989; Ramachandran et al. 1992). It’s a good indicator of
forest disturbance. Because of its widespread distribution across almost the entire
subcontinent, it is currently classified as ‘Least Concern’ on the IUCN Red
List. However, due to anthropogenic activities such as deforestation and
habitat fragmentation, this species is declining (Rajamani
& Marsh 2010).
The density of squirrel in Bhimashankar
Rai (Riparian area within Bhimashankar) was reported
to be 100 individual/km2 (Borges et al. 1989). From 1992 to 1993,
Mali et al. (1998) and Somnathan et al. (2007)
conducted a status survey of Ratufa indica
in protected areas and intervening reserved forests in the Western Ghats and
central India. The survey confirmed the extinction of Ratufa
indica dealbata in Gujarat and the vulnerable status of Ratufa
indica in the Western Ghats of Maharashtra. The researcher also compared
the Indian Giant Squirrel’s home range and distribution in Bhimashankar
Wildlife Sanctuary (Borges et al. 2007; Somnathan et
al. 2007; Mehta et al. 2012). According to data from the intensive study area,
the population’s home range had decreased by 20% after a seven-year gap. The
main reason for this decline was habitat degradation in the Bhimashankar
Wildlife Sanctuary (Borges et al. 2007; Somnathan et
al. 2007; Mehta et al. 2012).
Materials and Methods
Study area
In 2019, this research was conducted throughout the Bhimshankar Wildlife Sanctuary (BWS). The sanctuary is
located between the coordinates 19.132 0N and 73.554 0E.
It has a total area of 131 km2 (51 sq.mi.)
and is located in the northern part of Maharashtra, in the Western Ghats. The
sanctuary contains a variety of habitats, including steep slopes, plateaus,
uplands, gorges, valleys, and cliffs. In the sanctuary’s heart is an ancient
Shiva temple. It is close to the source of the Bhima River. Bhimashankar
has two ranges: Bhima 1 (Bhimashankar, Ahupe, Bhorgiri, Kondwal, Nigdale, Sakeri, Bhatti, Pathan, Yelavli,
and Ghatghar beat.) and Bhima 2 (Slope and Plains on
the konkan side of Bhimashankar,
Razpa, Khopivali, Narivali, Zamburde, Dongarnave, Khandas, and Nandgaon
beat).
The rainy season (June–October) brings an average of
3,000 mm of rain to BWS. Seasonal montane cloud forests can be found here.
These forests have high conservation value because they serve as water
catchment areas. Furthermore, the protected areas are rich in endemics such as
epiphytes and bryophytes. The sanctuary is said to be home to over 529 faunal
species, including the Giant Squirrel, Leopard, Golden Jackal, and Mouse Deer.
Furthermore, approximately 20% of the mammals reported by BWS are listed in
Schedule I of the Wildlife Protection Act (Borges et al. 1992; Somanathan et al. 2007).
The tropical ecosystem relies heavily on vegetation.
The sanctuary’s vegetation consists of evergreen, semi-evergreen, and
moist-deciduous forests, with the latter two being the most prevalent.
Mangifera indica, Olea dioica, Macaranga peltate, Memecylon
umbellatum, Atlantia racemose, and Xantolis tomentosa are the main plant species
in this sanctuary. Carvia callosa
is widely distributed throughout the sanctuary (Ghate
et al. 1994).
Population
density
To estimate the population density of giant squirrels
in the study area, the line transect method (Jathanna
et al. 2008; Thomas et al. 2010) and distance sampling method were used. Field
sampling was conducted from 20 May to 30 June 2019. During the study, we
sampled the abundance of the squirrel using 43 randomly selected line
transects. Each transect was surveyed between 0600 & 1000 h and 1600 &
1830 h. Each transect was different in length, ranging from 1–3 km. The
squirrel was observed directly using a portable Garmin GPS etrex
10 receiver. A Bunshell pro
Yardage sport 450 rangefinder was used to measure the direct distance of the
observation, the height of the sighting, and the tree height. The population
density of the Indian Giant Squirrel was estimated using distance-sampling
techniques and a modelled detection function using the software Distance;
version 6.0 (Thomas et al. 2010). The model with the Akaike information
criteria (AIC) was chosen (Jathanna et al. 2008;
Thomas et al. 2010). Squirrel cluster density (C) and standard errors were
estimated by grouping the data into 10 m perpendicular intervals. To select the
best model for estimating density, we used the minimum AIC as the standard
model selection procedure.
Nesting
characteristics
Data were collected when the
squirrels were most active and visible in the morning between 0600 h & 1000
h and in the evening between 1600 h & 1830 h. To sample the squirrel nests,
line transects were randomly placed. Nest quality (old/new), size, shape,
thickness, and leaf compositions of the nest, host tree, tree height, girth at
breast height (GBH), canopy height and continuity, and height of the nest from
the ground were all measured. The nest’s locations were recorded using a
portable GPS receiver, the etrex 10. Trees were
defined as plants with girths greater than 10 cm at breast height. DSLR camera
(NIKON D3400) were used to photograph the nests and squirrels. Wherever
possible, a standard Olympus binocular was used for observations as well as the
identification of leaves used to build the nests.
Results and Discussion
Population
density
There were 223 sightings of Indian Giant Squirrels
within the sanctuary’s 43 line transect totalling 60
km. Half-normal with cosine proved to be the best fit for giant squirrel data
based on the lowest AIC value (311.5) the encounter rate was 61.2 km per hour
walked. The squirrel is known to be a solitary animal, as evidence by this
study, which recorded no more than two individuals in a group. The mean group
size was 0.929, and the group density per square km was 13.929 ± 0.18, in BWS
(Table 1).
In comparison to reports from southern and central
India (Jathanna et al. 2008; Baskaran et al. 2011),
it is clear that the Indian Giant Squirrel population at BWS is relatively
dense (Table 2). The variation in different estimates used and the differences
between habitat types in the different studies could be the cause. Seasonal
variation and observer differences, on the other hand, limit the comparison.
Climate, environment, and topography all play a role in the distribution of
this species. Several studies have suggested that tree cover and food plant
diversity have a significant impact on the presence of the Indian Giant
Squirrel in tropical areas (Jathanna et al. 2008;
Baskaran et al. 2011; Mehta & Kulkarni 2011). The presence of a continuous
canopy and the availability of more food plant species will allow for more favourable conditions in terms of their density. As a
result of our research, BWS has the second largest population of Indian Giant
Squirrels in India (Borges et al. 1999; Jathanna et
al. 2008; Baskaran et al. 2011; Mehta & Kulkarni. 2011; Gurjar
et al. 2013; Palei et al. 2015).
Habitat use and status
Forests are currently found in small fragments or
riverine strips. They are thus frequently seen in Maharashtra’s sacred groves
and hill stations like Mahabaleshwer and Matheran, where the forest has been left relatively intact.
As a result, the population’s local status ranges from near threatened to
endangered, and even locally extinct. This the determined by the size and
integrity of the forest, the availability and abundance of food (floral
diversity), and the appearance of the forest in areas where poaching is
prohibited. Furthermore, connectivity between forest fragments may be linked to
hunting pressure in forest corridors outside of protected areas. However,
residents of Bhimashankar claim that this is no
longer a serious concern (Image 1).
Food sources in most tropical forests are distributed
at random in space and time (Fleming et al. 1987; Schaik et al. 1993). The
giant squirrel, like other species, requires a diverse landscape with the
preferred resources. Only 9% to 11% of tree species were not utilised by the giant squirrel (Borges et al. 2007) (Image
4 & 5).
Giant squirrels adapted to their arboreal habitat
through a variety of morphological and behavioural
adaptations. It is mostly graceful and can perform breathtaking leaps between
trees. It feeds while suspended by its hind limbs only. Its long tails serve as
a balancing mechanism. They used their teeth to break tree twigs and use those
twigs to build their nests. Surprisingly, when food is scarce, these squirrels
feed on the nesting materials (Borges et al. 1993a; Datta et al. 1998). The
availability of resources and the costs of defence
response are usually linked to aggressive and territorial behaviour
(Datta & Goyal 1996; Baskaran et al. 2011) (Image 6).
Nesting
Nest characteristics: The Indian Giant Squirrel uses
leaves and twigs to build large multi-layered globular shaped single chambered
nests or dreys. These dreys
are used for resting and sleeping, as well as nurseries. The size of the nest
varies, but the largest one seen was about 75 cm x 60 cm.
The nests were typically built away from the main tree
trunks, but approximately 10% of the dreys were found
adjacent to the tree trunks or on thick branches. Because of the falling
leaves, the nest was most easily found in march and April. During the monsoon
season, nests remained mostly hidden in the canopy and were difficult to find
due to the dense canopy (Image 2).
The globular dreys are
usually built at the intersection of crowns of neighbouring
trees. This allowed the squirrels to easily move from the drey
to other trees for foraging and other daily activities. This observation is
similar to Ramachandran (1998) and Rout & Swain (1996). A few nests were
also constructed on trees that had no continuity with neighbouring
trees.
Dreys
were constructed by gathering soft leaves from nesting trees as well as other
plant species such as Butea monosperma, Mangifera
indica, Syzygium cumini,
and Mallotus phillippensis.
These squirrels do not always use the leaves of the host plants where their
dreys are located. As a result, more research is
needed to understand why some trees are used for nesting but their leaves
cannot be used for the nest building. The nest’s consistency and rigidity were
achieved through the interweaving of leaves. According to a study of old and
newly constructed fallen nests, the leaves were deposited in 4 to 5 layers,
with the inner layer becoming soft and mat-like (Image 3).
Within its home range, the Indian Giant Squirrel
builds multiple nests (6–8), 3–4 of which are used concurrently (Borges et al.
2007). During the survey, 4,224 dreys and 223
squirrels were spotted, with 27 directly using the nests. While 196 could be
seen feeding or resting on the thick branches of the trees. Some squirrels may
be resting in the dreys. As a result, the number of dreys was far greater than the total number of squirrel
sightings.
Nesting Trees: During this survey, 4,224 dreys were supported by a total of 4,253 nesting trees from
52 tree species (Table 3). 51.51% were new and 47.80% were old. Mangifera
indica (Amba) and Olea dioica (Karap) were
the most preferred nesting trees, supporting 15.57% and 14.65% dreys, respectively (Figure 2). As a result, approximately
one-third of the dreys are built solely on two tree
species that were not the most abundant trees on the site. It suggests that
squirrels prefer specific trees to build their dreys.
The reason could be the feeding habitat and the quality of the leaves used as
nest construction material.
Nesting (Dreys): Indian
Giant Squirrel builds new globular nests out of green leaves, twigs, and
branches. The dry and moist leaves, twigs, and branches are old, and some have
fallen to the ground or nest materials have become unsettled. This observation
is sufficient to identify the old nest.
Number of dreys vs Number of
trees
Mangifera indica, Olea
dioica, Mallotus phillippensis,
Syzygium cumini,
Terminalia chebula, Ficus racemosa,
and Amerphophallus commutatus
are the most common tree species in the forest. As a result, the squirrels
do not choose the tree at random for nesting. However, leaves such as Olea
dioica and Mallotus phillippensis
are used selectively to construct the nests (Figure 4).
Tree height and nest height
The nest was observed in trees ranging in height from
3–45 m. Trees heights less than 9 m and greater than 36.5 m are only chosen on
rare occasions (Figure 5). As a result, the number of dreys
on these smaller trees was noticeably lower (Table 4).
According to the observation, the most preferred tree
height classes for nesting of Indian Giant Squirrels were 12–24 m, which
supported 60.16% of the total observed dreys. Tree
heights less than 12 m supported only 11.40% dreys,
while tree heights greater than 24 m supported only 28.42% dreys.
The percentage of dreys on different tree height
classes thus represents the Indian Giant Squirrels nesting preference at
various heights. This highlights the importance of old-growth tall trees with
large interconnected canopies that provide ideal habitat for giant squirrels.
The dreys were built in the middle of small branches
at a mean height of about 15 m above the ground, usually in the trees
sub-canopy. The average tree height minus the average nesting heights was found
to be 2.3 m. Based on the data, it can be concluded that the majority of the dreys were located very close to the top canopy, which
protects the squirrels and their young from large predators such as Jungle
cats, civets, Leopards, snakes, and raptors.
Each giant squirrel builds several nests within its
territory. Nest building is an important activity and squirrels spent nearly 3%
of total hours per day (Borges 1989a). Due to population density and the fact
that some adults also use other nests, nest parasitism can be seen in Indian
Giant Squirrels (Borges et al. 1999). Nests are large, dome-shaped structures
with lateral opening, constructed using a framework of twigs and lined by leaf
sprays usually built-in tall trees. Nursery nests are large and are built
either in trees densely overgrown with lianas or in those with wide-spreading
branches. The nests facilitate insulated resting places throughout the
territory. This avoids extremes of temperature and rain at any time (Borges
1989b). In addition, rotation of nest may also help to reduce ectoparasite load
on the squirrels.
Nest construction was mostly similar in pattern. It
was constructed by depositing a large no of forked twigs with leaves. The
leaves were arranged in three to four layers. The nest-building process Indian
giant squirrel includes a gathering of materials (cutting twigs, peeling
barks), carrying materials in the mouth to the nest site, and placing materials
in the nest once completed. At the building site, the twigs were forced into
place with a forwarding thrusting movement of the snout and alternate stamping
motion of the forefeet (Kumbhar et al. 2012). The
squirrel frequently builds dreys and uses more than
one nest within his territory. Nonetheless, they came to the nest every morning
and evening. The Indian giant squirrel did not use the nest on the first day of
completion, but it was used by the individuals the following day. The total
time spent on the nest building was approximately 2.5 hours. The occurrence of
multiple nest might be either to escape from predators
like langurs, Bonnet Monkeys, small cats or to provide protection from climatic
factors like temperature, cold, and rain. Freshly constructed nests were
observed from May to June. Yet the multiple nest phenomenon requires further
investigation.
The nest of the Indian Giant Squirrel was distinct
from a bird’s nest in having leaves of nesting trees interwoven in the middle
of the trees. The nest was either round or oval. The entry of the nest was
placed horizontally to the ground. The entrance was around 10 cm in diameter.
All nests sighted in the study area were observed to be east-facing, which
might be related to morning sunlight. The depth of the nest was 48 cm and the
inner diameter was 24 cm. Only a few hairs and food particles were found in the
nest chamber but no faecal matter. One old nest of
the Indian Giant Squirrel was located in Ficus racemosa
where 113 twigs were used for constructing that nest. Nests were very often
found at the highest point on the tree that offered maximum security and
protection to the animal (Pradhan et al. 2012).
Conclusion
The finding of the present study suggests the
significant importance of the conservation of the Indian Giant Squirrel and its
habitat. It will facilitate further research on the density and nutrient
composition of forage plants of the species. The tropical forests are in danger
of losing their habitats due to anthropogenic activities such as grazing and
firewood collection, which indicates a decline in the population of giant
squirrels in these areas. More significant conservation implementation
measures, such as nature trails and roads, can be well planned. Therefore, the provision of adequate forest
officers to monitor the animal and systematic scientific research focusing on
an inclusive conservation strategy are a matter of urgent need. It is not only
restoring the habitat and control the anthropogenic pressure but also helps the
long-term conservation and management of the species.
Table
1. Population density and average group size of Indian Giant Squirrel
(density/km2) estimated in Bhimashankar Wildlife
Sanctuary.
|
Parameters |
Value |
|
No. of transects |
43 |
|
Effort
(km) |
60 |
|
Number of group detection (n) |
223 |
|
Key function model |
Half-normal
key |
|
Key adjustment |
Cosine |
|
Detection probability |
37.6 |
|
Effective strip
width (m) |
1.0 |
|
Encounter rate
of group/km (n/l) |
3.7 |
|
Encounter rate
% CV |
61.2 |
|
Mean group
size |
0.929 |
|
Group density/km2 |
13.929
± 0.18 |
|
Group density
% CV |
1.35 |
|
Group density 95% CI |
13.56 |
|
AIC |
311.5 |
Table
2. Density estimates of the Indian Giant Squirrel by earlier studies in India.
|
Study
area |
Density/km2
of Indian giant squirrel |
Authors |
|
Bhimasankar Wildlife
Sanctuary |
13.92 |
Present
study |
|
Similipal Tiger
Reserve |
25.6 |
Palei et al.
(2015) |
|
Satpura National
Park |
5.59 |
Gurjar et al.
(2013) |
|
Madumalai Tiger
Reserve |
6.4 |
Ramesh
et al. (2012) |
|
Madumalai Wildlife
Sanctuary |
2.9 |
Baskaran
et al. (2011) |
|
Bandipur Tiger
Reserve |
2.36 |
Jathana et al.
(2008) |
|
Bhandra Tiger
Reserve |
12.25 |
Jathana et al.
(2008) |
|
Bhimasankar Wildlife
Sanctuary |
12.4 |
Borges
et al. (1999) |
|
Bhimasankar Wildlife
Sanctuary |
15.89 |
Mehta
et al. (2011) |
Table
3. Nesting behavior and nesting characteristics of Indian Giant Squirrel at Bhimashankar Wildlife Sanctuary.
|
|
Nesting tree species |
Local name |
No. of trees |
Old nest |
New nest |
No. of dreys |
% of trees |
% of dreys |
|
1 |
Acalypha
brachustachya |
Khokali |
2 |
0 |
2 |
2 |
0.05% |
0.05% |
|
2 |
Actinodaphne |
Malva |
345 |
160 |
167 |
327 |
8.11% |
7.74% |
|
3 |
Amerphophallus commutatus |
Loth |
156 |
88 |
89 |
177 |
3.67% |
4.19% |
|
4 |
Anogeissus
latifolia |
Dhavda |
2 |
0 |
1 |
1 |
0.05% |
0.02% |
|
5 |
Atalantia |
Chingar |
89 |
47 |
42 |
89 |
2.09% |
2.11% |
|
6 |
Bombax
Ceiba |
Savar |
1 |
0 |
1 |
1 |
0.02% |
0.02% |
|
7 |
Bridelia squamosa |
Ashind |
8 |
3 |
8 |
11 |
0.19% |
0.26% |
|
8 |
Bridellia retusa |
Asana |
3 |
1 |
2 |
3 |
0.07% |
0.07% |
|
9 |
Butea
menosperma |
Palas |
24 |
17 |
10 |
27 |
0.56% |
0.64% |
|
10 |
Caesalpinia
decaletala |
Chilahr |
48 |
24 |
28 |
52 |
1.13% |
1.23% |
|
11 |
Careya arberea |
Kumbh |
1 |
0 |
1 |
1 |
0.02% |
0.02% |
|
12 |
Catunaregam spinosatirumes |
Gel |
11 |
9 |
5 |
14 |
0.26% |
0.33% |
|
13 |
Chrysopogon zizanioides |
Yalaa |
74 |
41 |
35 |
76 |
1.74% |
1.80% |
|
14 |
Dimocarpus longam |
Umb |
1 |
1 |
0 |
1 |
0.02% |
0.02% |
|
15 |
Ficus
arnottiana |
Payar |
1 |
1 |
0 |
1 |
0.02% |
0.02% |
|
16 |
Ficus
racemosa L. |
Umber |
45 |
36 |
35 |
71 |
1.06% |
1.68% |
|
17 |
Glochidion ellipticum |
Bhoma |
1 |
0 |
1 |
1 |
0.02% |
0.02% |
|
18 |
Gracinia talbotii |
Fanasada |
33 |
11 |
22 |
33 |
0.78% |
0.78% |
|
19 |
Grewia
serrulata |
Dhaman |
20 |
10 |
10 |
20 |
0.47% |
0.47% |
|
20 |
Heterophragma quadriloculare |
Varas |
41 |
17 |
26 |
43 |
0.96% |
1.02% |
|
21 |
Jatropa curcus |
Aranda |
3 |
4 |
2 |
6 |
0.07% |
0.14% |
|
22 |
Konkiri |
Konkiri |
11 |
6 |
11 |
17 |
0.26% |
0.40% |
|
23 |
Lepisanthes tetraphylla |
Lokhandi |
7 |
3 |
4 |
7 |
0.16% |
0.17% |
|
24 |
Macaranga
peltata |
Chandada |
163 |
87 |
79 |
166 |
3.83% |
3.93% |
|
25 |
Mallotus phillippensis |
Shendri |
416 |
179 |
212 |
391 |
9.78% |
9.26% |
|
26 |
Mangifera
indica |
Amba |
662 |
285 |
343 |
628 |
15.57% |
14.87% |
|
27 |
Mitragyna parvifolia |
Kalmba |
4 |
0 |
2 |
2 |
0.09% |
0.05% |
|
28 |
Olea
dioica |
Karambu |
354 |
187 |
191 |
378 |
8.32% |
8.95% |
|
29 |
Olea
dioica |
Karap |
623 |
287 |
324 |
611 |
14.65% |
14.46% |
|
30 |
Phyllanthus
emblica |
Avla |
1 |
1 |
0 |
1 |
0.02% |
0.02% |
|
31 |
Pongamia pinnata |
Karanj |
5 |
2 |
4 |
6 |
0.12% |
0.14% |
|
32 |
Schleichera oleosa |
koshimba |
6 |
5 |
4 |
9 |
0.14% |
0.21% |
|
33 |
Sideroxylon (Xantolis) tomentosa |
Kombal |
196 |
113 |
70 |
183 |
4.61% |
4.33% |
|
34 |
Syzygium cumini |
Jambal |
326 |
142 |
164 |
306 |
7.67% |
7.24% |
|
35 |
Terminalia
chebula |
Majkudhal |
92 |
44 |
45 |
89 |
2.16% |
2.11% |
|
36 |
Terminalia
chebula |
Heerda |
53 |
24 |
29 |
53 |
1.25% |
1.25% |
|
37 |
Terminalia
cuneata |
Sadhda |
132 |
63 |
67 |
130 |
3.10% |
3.08% |
|
38 |
Terminalia
eliptica |
Ain |
4 |
2 |
2 |
4 |
0.09% |
0.09% |
|
39 |
- |
Pipar |
106 |
53 |
53 |
106 |
2.49% |
2.51% |
|
40 |
- |
Vondara |
1 |
0 |
1 |
1 |
0.02% |
0.02% |
|
41 |
- |
Sayar |
1 |
0 |
1 |
1 |
0.02% |
0.02% |
|
42 |
- |
Adhal |
8 |
2 |
5 |
7 |
0.19% |
0.17% |
|
43 |
- |
Pavti |
53 |
20 |
26 |
46 |
1.25% |
1.09% |
|
44 |
- |
Sandha |
96 |
52 |
55 |
107 |
2.26% |
2.53% |
|
45 |
- |
Aayna |
3 |
0 |
1 |
1 |
0.07% |
0.02% |
|
46 |
- |
Bhonda |
1 |
0 |
1 |
1 |
0.02% |
0.02% |
|
47 |
- |
Ambakura |
7 |
1 |
2 |
3 |
0.16% |
0.07% |
|
48 |
- |
Paba |
7 |
3 |
4 |
7 |
0.16% |
0.17% |
|
49 |
- |
Padal |
1 |
1 |
0 |
1 |
0.02% |
0.02% |
|
50 |
- |
Pareli |
2 |
0 |
2 |
2 |
0.05% |
0.05% |
|
51 |
- |
Varul |
1 |
0 |
1 |
1 |
0.02% |
0.02% |
|
52 |
- |
Sajeri |
2 |
1 |
1 |
2 |
0.05% |
0.05% |
|
|
Total |
|
4253 |
2033 |
2191 |
4224 |
100.00% |
100.00% |
Table
4. The height class intervals with the numbers of dreys,
number of trees, and number of new and old dreys.
|
Tree
height (class interval) |
Class
AV. Tree height (m) |
No.
of trees |
No.
of dreys |
Old
nests |
New
nests |
%
Of dreys |
|
10–19 |
4.5 |
120 |
118 |
43 |
75 |
2.793561 |
|
20–29 |
7.5 |
145 |
142 |
46 |
96 |
3.361742 |
|
30–39 |
10.6 |
220 |
218 |
95 |
123 |
5.160985 |
|
40–49 |
13.6 |
627 |
624 |
177 |
447 |
14.77273 |
|
50–59 |
16.6 |
755 |
753 |
270 |
483 |
17.8267 |
|
60–69 |
19.7 |
602 |
600 |
238 |
362 |
14.20455 |
|
70–79 |
22.7 |
575 |
571 |
282 |
289 |
13.51799 |
|
80–89 |
25.7 |
258 |
256 |
118 |
138 |
6.060606 |
|
90–99 |
28.8 |
150 |
149 |
65 |
84 |
3.527462 |
|
100–109 |
31.8 |
220 |
218 |
117 |
101 |
5.160985 |
|
110–119 |
34.8 |
170 |
168 |
72 |
96 |
3.977273 |
|
120–129 |
37.9 |
115 |
114 |
52 |
62 |
2.698864 |
|
130–139 |
41.0 |
170 |
169 |
87 |
82 |
4.000947 |
|
140–149 |
43.9 |
126 |
124 |
55 |
69 |
2.935606 |
|
Total |
|
4253 |
4224 |
1717 |
2507 |
100% |
For images
and graphs—click here for full PDF.
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