CHAPTER V
HABITAT UTILIZATION
5.1 Introduction
The term habitat is usually defined as a dominant vegetation formation, e.g. forest,
meadow or wetland (Ricklefs and Miller, 1999), the definition and meaning of habitat
heterogeneity varies considerably. Different types of habitat available in an area, which are
used by individuals or groups, are not in equal proportions.
The seasonal variation of food availability, such as burning of grassland and annual
flood also affects the variation of habitat utilization pattern of herbivorous animals (Lahon
and Sonowal, 1973; Deb Roy, 1986). Individual habitat selection reflects the basic
necessities of the species such as food, water and cover. But, species specific variation in
habitat selection pattern has been always there. This is because of the reason that, each
species has got certain specific food choice, which may not be available in each area of the
home range (Bell, 1971). Elephant foraging activities affects the configuration and species
composition of plant communities within their habitats. Elephants impose landscape level
impacts upon their habitats by maintaining older seral stages of plant succession, with farreaching effects upon the plant and animal species therein. The physical modifications
imposed by elephants upon their environments such as pathways, water seeps and opening
up of understorey vegetation may tend to offset competition for forage between elephants
and other sympatric ungulate species. Elephants are capable of greatly affecting the structure
of vegetation and perhaps animal communities (Cumming, 1982; Western, 1989). At high
densities, elephants reduces woodlands and keep on converting them to more open grassland
(Laws et al., 1975; Cumming, 1982; Western, 1989). Herbivores favouring ecotone and
forest grassland mosaic habitats can benefit from the presence of elephants, whose activities
tend to maintain these communities at the expense of closed-canopy forest habitats. In most
habitats, plant communities determine the physical structure of the environment and
therefore, have a considerable influence on the distributions and interactions of animal
species (Lawton, 1983; McCoy and Bell, 1991). Species preferring closed-canopy habitats,
such as arboreal primates, may be adversely affected for these same reasons (Eisenberg,
1980).
It has been disastrous for elephant populations as the elephants need not only
grassland, but also forest for meeting their nutritional requirements (Lahiri-Choudhury,
1980; Sukumar, 1989b). Elephants may also be subject to heat stress in the absence of
adequate shade in pure grasslands (Sukumar, 1994b). Grasslands are the preferred feeding
habitat of elephants; they do however, need other habitats for movements, resting, shade
(cover), breeding and other purposes (Ishwaran, 2001). Feeding preferences and behaviour
of Asian elephant are known to change over time due to changes in its habitat (Iswaran, Op.
cit.).
As people continue to occupy more and more forest land for settlement, agriculture
and construction of building and dams and other forms of development, the shrinking habitat
area compresses the wildlife population to levels beyond carrying capacity (Sukumar,
1994a). Presently, a number of wildlife habitats have undergone or are being threatened with
the fragmentation due to various anthropogenic factors and this has adversely affected the
larger mammalian populations residing in it (Johnsingh et al., 1990). The long-term effects
will include genetic isolation, habitat fragmentation within the same forest and enhancement
in the human-elephant conflict in adjoining areas. Genetic isolation of elephant populations
may also increase the chances of replacement of interbreeding to intra-breeding and thereby
reduce the population persistence, even for wide ranging wildlife species (Joshi and Singh,
2008).
In India Asian elephant habitats were studied by Ali, et al. (1983-84), Daniel et al.
(1987), Singh and Chowdhury (1999), Choudhury (2002), Kushwaha and Hazarika (2004),
Varma et al. (2008), Williams (2003), Williams et al. (2008)and Zhang and Wang (2003).
In North-Eastern India, there are wide varieties of savannah ecosystems, depending
upon various origins from a number of forest types, ranging from tropical rain forest,
through sub-tropical and humid mountain forests to temperate forest (Champion and Seth,
1968; Puri, 1960). Presently, most of the elephant habitats are destructed by various
development activities like road construction, industrial development, slash and burning
cultivation, construction of the hydro electric projects and as well as by natural cause like
river erosion, sedimentation etc. But, information and assessment on habitat of Asian
elephant in North-East India has been found scanty except the assessment of habitat loss in
Kameng and Sonitpur Reserves by Kushwaha and Hazarika (2004). They also found that,
the moist mixed deciduous forest, which supports highest biodiversity in Assam are facing
maximum deforestation. However, little is known about the habitat utilization pattern of
Asian elephant in Manas National Park till inception of this study.
Hence, it is very much essential for the protected area managers and conservation
planners to know the habitat utilization and selection pattern of endangered species like
Asian elephant to identify the critical habitat requirements to protect these from the
anthropogenic pressure of the ever increasing human population. Thus, the study of habitat
utilization pattern of Asian elephant in Manas National Park has been designed to fulfill
these requirements and can be used in other areas as the Manas National Park has mixture of
grassland habitat and woodland habitats.
5.2 Objective
The main objective of this chapter is to investigate the habitat utilization pattern of
Asian elephant in Manas National Park.
Present study has tried to answer the following question based on above objectives1. What were the available habitats of Asian elephant and landscape matrix of these
habitats in Manas National Park?
2. What was the relative habitat use of Asian elephant in Manas National Park?
3. Was there any fluctuation of habitat utilization of Asian elephant during different
time slots of day viz. Morning-(06:00 – 10.00 hrs.), Noon (10:00 – 14:00 hrs.),
Afternoon (14:00 – 18:00 hrs.) and correlation with the fluctuation of temperature in
these three time slots of the day?
4. What was the habitat selectivity of Asian elephant in different types of habitat in
MNP?
5.3 Methods
To find out the habitat utilization and the selectivity of Asian elephant, all the
existing different habitat types of MNP has been categorised and then the satellite imagery
was analysed to record the area under different habitat categories.
5.3.1 Categorization Methods
5.3.1.1 Habitat Classification
For the categorization of habitat ground truthing with the help of satellite image and
GPS locations in different representative types of habitat.
5.3.1.1.1 Satellite imagery
The satellite image of Manas National Park was obtained from National Remote
Sensing Agency, Secoderbad.
5.3.1.1.2 Habitat Types
The different habitat types found in Manas National Park are such as evergreen
forest, semi evergreen forest, moist mixed deciduous forest, tall grassland, wet grassland,
short grassland which formed the major habitats and rest was classified as miscellaneous
habitat. The characteristics of these habitats were observed in the field, based on the
description of Champion and Seth (1968).
5.3.1.2 Ground truthing
To rectify the false colour composition and to standardize the colour specification of
the satellite imagery, field visits were made to locate above representative vegetation types
during study period. While observing the different habitats in field, GPS readings were
recorded with respect to habitat types, which then incorporated at the satellite imagery to
determine the variation in habitat types in regards to the coloration. These data were
incorporated into the Geographical Information System (GIS). The GPS data were then
imported to satellite imagery and thus habitats were classified accordingly by using
supervised classification in ERDAS software. Based on the specific area in different colour
of satellite imagery, the landscape matrix of Manas National Park was calculated.
5.3.2 Habitat utilization pattern
The same methods that were used for measuring the home range size of elephants
also used for measuring the habitat utilization pattern. Whenever the Asian elephant sighted,
the types of habitat, GPS location, number of Asian elephant sighted were recorded. The
timings of Asian elephant sighting were also recorded. The time period of the day viz.
Morning-(06:00 – 10.00 hrs.), Noon (10:00 – 14:00 hrs.), Afternoon (14:00 – 18:00 hrs.),
during which the elephant were encountered in that particular habitat has been also recorded.
After locating the elephants, the scan animal sampling and Ad. Libitum Sampling (Altmann,
1974) methods were used to collect data on the time spent. Total of 4320 hours of scan
animal sampling and Ad. Libitum Sampling were done for Asian elephant in Manas
National Park during study period. The relative habitat use pattern was calculated by using
the following formulaHabitat utilization of H1 by Asian elephant
Habitat utilization (%) =
Habitat utilization by Asian elephant in
× 100
all habitats (H1+H2+…..+Hn )
(Where H1, H2,......Hn= Habitats utilized by Asian elephant in MNP)
5.3.3 Temperature fluctuation in a day
There has been robust temperature fluctuation in different hours of the day. To get
the clear picture of temperature fluctuation the temperature was recorded in three times a
day viz. Morning-(06:00 – 10.00 hrs.), Noon (10:00 – 14:00 hrs.), Afternoon (14:00 – 18:00
hrs.) covering all the four seasons of the year. The temperature was recorded in the Dwimari
camp, which was in the central location of Manas National Park and on the Indo-Bhutan
border.
5.3.4 Fluctuation of habitat utilization from the expected level
As there were seven different habitat types in MNP that, were considered to be
utilized by elephant homogenously i.e. expected relative habitat utilization will be 14.29 %.
Deviation of habitat utilization (relative %) by Asian elephant from this level was calculated
to observe the habitat utilization preferences.
5.3.5 Habitat Selectivity
The variation in habitat use by Asian elephant was supposed to be based on
availability of the specific types of habitat. So, the selectivity of the different habitat was
calculated to find out the habitat preference. The standardized habitat selection index for
constants resources was used to compare habitat selection of Asian elephant in different
habitats at Manas National Park. This index was chosen, because it does not fluctuate with
inclusion or exclusion of seldom-used resources (Manly et al., 2002) and was considered
more versatile than other selection preferences indexes (Garshelis, 2002). The index was
based on the selection ratio Wi, which refers the proportional use of habitat divided by the
proportional availability of each resource. The formulae was as followsOi
Wi =
i
Where, Oi = Proportion of the sample of used habitat in category i;
i
=
Proportion of available resource in category i; i= evergreen forest/ semi evergreen
forest/ moist mixed deciduous forest/ tall grassland/ wet grassland/ short
grassland/ miscellaneous habitats.
A wi value larger than 1 indicates a positive selection for the resource and a value less than
1 indicates avoidance of the resource. A value around 1 indicates that, the resource was used
proportionately to its availability and no resource selection was noted.
5.4 Results
5.4.1 Habitats of Asian elephant
With the help of GIS, satellite image and ground truthing methods (GPS location)
seven major habitat types has been recognized in Manas National Park. These habitat types
were- Evergreen, Semi evergreen, Moist Mixed deciduous forest, Tall Grassland, Wet
Grassland, Short Grassland and Miscellaneous types (Figure 5.1). The vegetation
characteristics of these habitat types were found as follows-
i) Evergreen Forest (1B/C and 2B/C):
The evergreen forest habitat was dominated by Bagipoma (Chikrasia tabularis),
Bhelu (Tetramales nudiflora), Gonsori (Cinnamomum cicicodaphe), Badam (Mansonia
dipikae), Bonsum (Phoebe goalparensis), Titasap (Michelia champaca), Lali (Ammoora
wallichii), Dhuna (Canarium resiniferum), Khakan (Duabanga sonnerotoides), Gamari
(Gmelina arborea) etc. followed by Parali (Stereospermum personatum), Oxi (Dillenia
pentagyna), Nahar (Mesua ferea), Cham (Artocarpus chaplasa), Barham-thuri (Talauma
hodgsonii), Larubandha (Macaranga denticulatus) etc.
Shrubs species were Kathanaphul (Moninda angustifolia), Kukurathengia (Leea
sps.), Kawla (Litsea spp.), Chorat (Laportea crenulata), Tora (Alpinia allughas), Dhopat tita
(Clerodendron infortunatum), Kamini Kanchan (Murraya exotica), Narasingha (Murraya
kaengii), Pipoli (Piper longum), Basaka (Adatoda vasica) etc.
Among grass species Khagori (Phragmites karka), Meghela (Saccharam procerum)
and shrubs Eupatorium odoratum etc. were present. Among climbers and epiphytes, the
very much conspicuous species found in this habitat were Ghila lota (Entada scandens) and
Kuchia lata (Acacia pinnata) etc. During present study this habitat was mentioned as
evergreen forest (Figure 5.1).
ii) Sub Himalayan High Alluvial Semi evergreen Forests:
2B/CI/ISI.
This type of habitat occurs on the high ground of the MNP on the northern boundary.
Three distinct sub types were recognized viz. (a) The Jam- Bhelu-Som sub type [(2B/CI/ISI
(b)], (b) The Sopa sub type [(2B/CI/ISI (C)], (c) The Bonsum sub type [CB/CI/ISI &
2B/CI/ISI (C)].
There was pure climax type occupying the upper deciduous to semi evergreen type
and the third was intermediate type (Figure 5.1).
a) The Jam- Bhelu-Som sub type: 2B/CI/ISI (b)
This type was transition belt from the deciduous to evergreen type of habitat. The
Tetramales nudiflora was the predominant species of this type. The associated tree species
were Syzigium cuminii, Tetramales nudiflora, Machilus bombycina, Stereospermum
personatum, Albizzia lebbek, Amoora wallichii, Chukrassia velutina, Pterospermum
acerifolium, Toona ciliate, Shorea robusta and, Phoebe goalparensis etc.
b) The Sopa sub type: 2B/CI/ISI (C)
The Sopa sub type occupies comparatively high ground above the Bonsum type. The
general canopy level and principal emergent associates were Tetramales nudiflora,
Acrocarpus fraxinifolium, Schimia wallichii, Phoebe goalparensis, Michalia champaca,
Sterculia alata and Pterospermum acerifolium etc.
c) The Bonsum (Phoebe goalparensis) sub type Approximate to CB/CI/ISI & 2B/CI/ISI
(C)
The Bonsum sub type represented climax vegetation of the locality and occupied a
high ground surrounded by other sub types. The conspicuous layer in the top canopy was
composed of scattered trees of Michelia champaca, Tetramales nudiflora, Phoebe
attenuate, Acrocarpus flexinifolius, Ailanthus grandis with Bombax ceiba along the river
bank. Below this layer the proper canopy occurs with Phoebe goalparensis, Sterculia
alata, Cinnamomum cecedodaphane, Schimia wallichii, Canarium species, Disoxylum
hamiltonii,
Gmelina
arborea,
Terminalia
bellirica,
Castonopsis
species
and
Pterospermum acerifolium, etc.
The third storey was composed of Machilus bombycina, Premna bengalensis etc.
The undergrowth characterized by species Morinda tinctoria, Leea sp., Adhatoda vasica
etc. and the ground cover consists of Coffea bengalensis and other evergreen shrubs. Thus
the habitat was mentioned as semi evergreen forest (Figure 5.1).
iii) Moist Eastern Himalayan Mixed Deciduous Forests – 3c/3Cb & 3c/C3 2SI.
This habitat represents the composition of both the above forest types. This type of
forest occurred in successional stage between the grassland and the semi-evergreen forest.
Variation in drainage and moisture retention capacity of the soil seems to be responsible
for exclusion of Sal (Shorea robusta) in this area in MNP. Thus the type has been
definitely in a transition stage in between the riparian forests and grassland in MNP and
was arrested at the pre-climax variation due to local variation of soil. The predominant
species in such areas were (associated of Sal) Terminilia bellirica, Sterculia villosa,
Lagerstroemia parviflora, Dillenia pentagyna, Michelia champaca, Allibizzia lebbek,
Strospermum personatum, Bombax ceiba and Fagara budrunga and Toona ciliate etc. The
middle storey was made up of saplings of the above species and Wrightia sp., Emblica sp.
and Bridelia sp. etc. In open canopy conditions Imperata sp., Anthistiria gigantia,
Saccharum sp., Clerodendron sp., Litsea sp., Coffea bengalensis were found as ground
cover. Thus the habitat was mentioned as moist mixed deciduous forest.
iv) Tall Grassland
This type of habitat occurred as patches of grassland and was characteristic of well
drained high land in the plain areas and usually comes in existence in old village clearing
and adjacent to village cultivated area. These areas were subject to heavy annual fire and
regeneration with heavy grass was often seen with other stunted fire hardy species such as
Dillenia scabrellia, Phoebe paniculata, Butea monosperma, Careya arborea, Dillenia
pentagyna and Dillenia indica etc.
The main grasses in this type of grassland in Manas National Park were Imperata
cylidrica, Themeda arundinacea, Themeda caudata, Arundo donax, Phragmites karka,
Themeda villosa, Saccharum spontaneum and Erianthus ravennae. The height of this
grassland was sometimes more than 5 meter, which was enough to cover an adult elephant.
The tree species scattered in grasses were Simul (Bombax ceiba), Koroi (Albizia procera),
Amlakhi (Emblica officianalis), Oxi (Dillenia pentagyna), Palash (Butea monosperma)
etc. Hereafter, this habitat has been mentioned as tall grassland (Figure 5.1).
v) Short Grassland
The main species were Imperata cylindrica, Sungrass Imperata arundinacea, Kush
Saccharum spontaneum and Meghela Saccharum procerum etc. However, species like Nal
(Arundo donax), Khagori (Phragmites karka), Ekara (Erianthus ravanae) etc. also
scattered in it. The tree species scattered in the short grassland were Simul (Bombax
ceiba), Koroi (Albizia procera), Amlakhi (Emblica officinalis), Oxi (Dillenia pentagyna)
and Palash (Butea monosperma) etc. Rare species like Reinwaeditia indica, Desmodium
motorum, Pueraria subspicata and Priden pilosa, etc. also found in the short grassland
habitat especially in Manas National Park. During present study this type of forest was
mentioned as short grassland (Figure 5.1).
vi) Eastern Wet alluvium Grassland (Terai formation)
This type of forest was found in Manas National Park especially on severely drained
and low lying locations with little change of composition. The grass species found were
Kush (Saccharum spontaneum), Kahua (Saccharum procerum), Khagori (Phragmites
karka), Ekara (Erianthus ravanae).
Among the tree species present were Koroi (Albizia procera), Urium (Bischofia
javanica), Owtenga (Dillenia indica), Bhelkar (Trewia nudiflora), Simul (Bombax ceiba)
etc. During present study this type of forest was mentioned as wet grassland (Figure 5.1).
vii) Miscellaneous
In the miscellaneous type of habitat the river and sand area, riparian fringing forest,
Khoir-sisoo forest, encroached cultivated area inside Manas National Park were included.
Other than the cultivated area the riparian fringing forest, Khoir-Sisoo forest contributed
major portion under this habitat category (Figure 5.1).
(a) Riparian Fringing Forests 4E/RSI
This type was consists of plant communities in seral stages found along the banks of
the streams that flow through the forest. The succession progresses according to the
formation of soil of the river bed with deposition of silts. The principal species were
Simul, Khoir, Sissoo. In the later stage, Albizzia procera, Bridelia retusa, Lagerstroemia
parviflora and a few species were more characteristic of the miscellaneous type come up.
(b) Khoir-Sissoo Forests. 5/IS2
This type comes under primary seral stage of succession of tropical dry deciduous
forest. This was found mainly in the Gabharukhunda area and Dwimari area of the Manas
National Park. The principal species in this type, as the name itself suggest were Acacia
catechu and Dalbergia sissoo growing either in admixture with each other or in separate
pure block. Young stands of Sissoo in excellent forms were seen in silt formed in beds of
the above rivers as well as the fresh silt deposits on the bank. Most of the growing stock
was young and only a few trees of utilizable size were available. But, due to the unstable
nature of the soil the excellent growth of the Sissoo or Khoir were often found uprooted
and washed away by the rivers during rainy season.
(c) Cultivated area
In the Manas National Park, more than 20 km2 area in the Panbari and Bhuyapara
Range were encroached by human. These areas were used mainly for cultivation of wet
and dry paddy
Figure 5.1 Map showing different types of habitat in Manas National Park.
5.4.2 Landscape Matrix
From the landscape matrix analysis this was found that, area of the Manas National
Park was mainly covered with 28.1 % of semi evergreen forest, followed by moist mixed
deciduous forest (26.7 %), tall grassland (22.32 %), wet grassland (11.4 %), miscellaneous
(5.31 %), short grassland (3.67 %) and least of 2.51% by evergreen forest (Figure 5.1,
Figure 5.2).
30
28.1
26.7
Relative area in MNP
25
22.32
20
15
11.4
10
5.31
5
3.67
2.51
0
Evergreen
Forest
Semievergreen Moist Mixed Tall Grassland Wet Grassland
Forest
Deciduous
Forest
Short
Grassland
Miscellaneous
Habitat
Figure 5.2 Landscape matrix of different types of habitat in Manas National Park.
5.4.3 Habitat Utilization Pattern
During the present study it was found that, annually Asian elephant utilized highest
of 28.33 % semi evergreen forest, followed by tall grassland (21.16 %), wet grassland
(19.76%), moist mixed deciduous forest (14.12 %), short grassland (8.14 %), evergreen
forest (4.38 %) and least of 4.11 % miscellaneous habitat in Manas National Park (Figure
Relative Habitat Utilization (%)
5.3).
28.33
30
25
19.76
20
14.12
15
8.14
10
5
21.16
4.38
4.11
0
Evergreen
forest
Semi evergreen Moist mixed
forest
deciduous
forest
Wet grassland Tall grassland Short grassland Miscellaneous
Habitat
Figure 5.3 Annual habitat utilization patterns of Asian elephant in Manas National Park.
5.4.4 Seasonal Habitat Utilization Pattern
The seasonal habitat utilization pattern of different habitats by Asian elephant was found
as followsA. Pre-Monsoon Season
During study period, it was found that Asian elephant utilized highest of 27.85 %
tall grassland during pre-monsoon season, followed by semi evergreen forest (27.81 %), wet
grassland (24.96 %), moist mixed deciduous forest (7.66 %), short grassland (6.69 %),
miscellaneous (3.14 %) and least of 1.89 % evergreen forest in Manas National Park (Figure
5.4-a).
B. Monsoon Season
During study period, it was found that during monsoon season Asian elephant utilized
highest of 30.64 % semi evergreen forest, followed by moist mixed deciduous forest (21.23
%), wet grassland (17.73 %), tall grassland (14.14 %), evergreen forest (8.23 %),
miscellaneous (5.71 %) and lest of 2.32 % short grassland habitat in Manas National Park
(Figure 5.4-b).
C. Retreating Monsoon Season
During study period, it was found that, during retreating monsoon season Asian
elephant utilized highest of 28.48 % semi evergreen forest, followed by tall grassland (22.44
%), wet grassland (21.39 %), moist mixed deciduous forest (15.26 %), short grassland (5.06
%), miscellaneous (4.35 %) and least of 3.02 % evergreen forest in Manas National Park
(Figure 5.4-c).
D. Winter Season
During study period, it was found that, during winter season Asian elephant utilized
highest of 26.39 % semi evergreen forest, followed by tall grassland (20.25 %), short
grassland (18.49 %), wet grassland (14.96 %), moist mixed deciduous forest (12.31 %),
evergreen forest (4.38 %) and least of 3.22 % miscellaneous in Manas National Park (Figure
5.4-d).
Relative Habitat Utilization
(%)
27.81
30
25
20
15
10
5
0
27.85
24.96
7.66
6.69
3.14
1.89
Evergreen
forest
Semi
evergreen
forest
Moist mixed Wet grasslandTall grassland
deciduous
forest
Short
grassland
Miscellaneous
Habitat
Relative Habitat Utilization (%)
(a) Pre-monsoon Season
35
30.64
30
25
21.23
17.73
20
14.14
15
10
8.23
5.71
2.32
5
0
Evergreen
forest
Semi
evergreen
forest
Moist mixed Wet grassland Tall grassland
deciduous
forest
Short
grassland
Miscellaneous
Habitat
Relative Habitat Utilization (%)
(b) Monsoon season
28.48
30
25
21.39
20
22.44
15.26
15
10
5
3.02
5.06
4.35
Short
grassland
Miscellaneous
0
Evergreen
forest
Semi
evergreen
forest
Moist mixed Wet grassland Tall grassland
deciduous
forest
Habitat
(c) Retreating Monsoon Season
Relative Habitat Utilization (%)
30
26.39
25
20.25
18.49
20
14.96
12.31
15
10
4.38
5
3.22
0
Evergreen
forest
Semi
evergreen
forest
Moist mixed
deciduous
forest
Wet
grassland
Tall grassland
Short
grassland
Miscellaneous
Habitat
(d) Winter Season
Figure 5.4 Habitat utilization pattern of Asian elephant during (a) Pre-monsoon, (b)
Monsoon (c) Retreating Monsoon and (d) Winter Season in Manas National Park.
5.4.5 Habitat Utilization Deviated From Expected Level
During study period it was found that, Asian elephant utilized semi evergreen forest
(14.04 %), tall grassland (6.87 %), wet grassland (5.47 %) habitat more than expected; while
it had used the
moist mixed deciduous forest (-0.17 %), short grassland (-6.15 %),
evergreen forest (-9.91 %), miscellaneous (-10.18 %) habitat less than expected in Manas
National Park ( Figure 5.5).
Annual relative habitat
utilization deviation from
expected (%)
20
14.04
15
10
5.47
6.87
5
0
-5
Evergreen
forest
Semi
evergreen
forest
-0.17
Moist mixed Wet grassland Tall grassland
deciduous
forest
-10
-9.91
-15
Short
grassland
Miscellaneous
-6.15
-10.18
Habitat
Figure 5.5 Annual habitat utilization deviation from expected level by Asian elephant in
Manas National Park.
A. Pre-monsoon Season
During study period, it was found that, during pre-monsoon season, Asian elephant
used the tall grassland (13.56 %), semi evergreen forest (13.52 %), wet grassland (10.67 %)
habitat more than expected; while it had used the moist mixed deciduous forest (-6.63 %),
short grassland (-7.6 %), miscellaneous (-11.15 %), evergreen forest (-12.4 %) habitat less
than expected in Manas National Park (Figure 5.6-a).
B. Monsoon Season
During study period, it was found that, during monsoon season, Asian elephant used
the semi evergreen forest (16.35 %), moist mixed deciduous forest (6.94 %), wet grassland
(3.44 %) more than expected; while it had used the tall grassland (-0.15 %), evergreen
forest (-6.06 %), miscellaneous (-8.58 %), short grassland (-11.97 %) habitat less than
expected in Manas National Park (Figure 5.6-b).
C. Retreating Monsoon Season
During study period, it was found that, during retreating monsoon season, Asian
elephant used the semi evergreen forest (14.19 %), tall grassland (8.15 %), wet grassland
(7.1 %), moist mixed deciduous forest (0.97 %) habitat more than expected; while it had
used the short grassland (-9.23 %), miscellaneous (-9.94 %), evergreen forest (-11.27 %)
habitat less than expected in Manas National Park (Figure 5.6-c).
D. Winter Season
During study period, it was found that, during winter season, Asian elephant used the
semi evergreen forest (12.1 %), tall grassland (5.96 %), short grassland (4.2 %), wet
grassland (0.67 %) habitat more than expected; while it had used the moist mixed deciduous
forest (-1.98 %), evergreen forest (-9.91 %), miscellaneous (-11.07 %) habitat less than
expected in Manas National Park (Figure 5.6-d).
Relative habitat utilization
deviation fromexpected (%)
during pre-monsoon
13.56
13.52
15
10.67
10
5
0
-5
Evergreen
forest
Semi
evergreen
forest
-6.63
-10
-15
Moist mixed Wet grasslandTall grassland
deciduous
forest
Short
Miscellaneous
grassland
-7.6
-11.15
-12.4
Habitat
(a) Pre-monsoon Season
Relative habitat utilization
deviation from expected (%)
during monsoon
20
16.35
15
10
6.94
3.44
5
0
-5
-10
Evergreen
forest
-6.06
Semi
evergreen
forest
Moist mixed Wet grasslandTall grassland
deciduous
-0.15
forest
Short
Miscellaneous
grassland
-8.58
-11.97
-15
Habitat
(b) Monsoon season
Relative habitat utilization
deviation fromexpected (%)
during retreating monsoon
20
14.19
15
10
7.1
5
8.15
0.97
0
-5
Evergreen
forest
Semi
evergreen
forest
Moist mixed Wet grasslandTall grassland
deciduous
forest
-10
-15
Short
Miscellaneous
grassland
-9.23
-11.27
Habitat
(c) Retreating Monsoon Season
-9.94
Relative habitat utilization
deviation from expected (%)
druing winter
15
12.1
10
5.96
4.2
5
0.67
0
-5
Evergreen
forest
Semi
evergreen
forest
Moist mixed Wet grasslandTall grassland
deciduous
forest
Short
Miscellaneous
grassland
-1.98
-10
-9.91
-15
-11.07
Habitat
(d) Winter Season
Figure 5.6 Habitat utilization deviations from expected level of Asian elephant during (a)
Pre-monsoon, (b) Monsoon (c) Retreating Monsoon and (d) Winter Season in Manas
National Park.
5.4.6 Fluctuation habitat utilization during different time slots
The habitat utilization pattern of Asian elephant in different slots of day viz.
Morning-(06:00 – 10.00 hrs.), Noon (10:00 – 14:00 hrs.), Afternoon (14:00 – 18:00 hrs.) in
different seasons were as followsA. Pre-monsoon Season
During present study it was found that, during morning hours of pre-monsoon
season, the Asian elephant utilized mostly the tall grassland (34.31 %), followed by
utilization of semi evergreen forest (22.4 %), wet grassland (17 %), moist mixed deciduous
forest (16.13 %), short grassland (5.38 %), evergreen forest (2.97 %) and least utilization of
miscellaneous (1.81 %) habitat in Manas National Park (Figure 5.7-(a); Table 5.2).
During present study it was found that, during noon hours of pre-monsoon season,
Asian elephant utilized mostly semi evergreen forest (33.62 %), followed by utilization of
wet grassland (22.01 %), tall grassland (15.74 %), short grassland (13.17 %), moist mixed
deciduous forest (10.28 %), miscellaneous (3.07 %) and least utilization of evergreen forest
(2.11 %) habitat in Manas National Park (Figure 5.7-(a); Table 5.2).
During present study it was found that, during afternoon hours of pre-monsoon
season, Asian elephant utilized mostly tall grassland (31.73 %), followed by utilization of
wet grassland (25.95 %), semi evergreen forest (29.01 %), short grassland (11.99 %), moist
mixed deciduous forest (7.07 %), miscellaneous (1.28 %) and least utilization of evergreen
forest (1.09 %) habitat in Manas National Park (Figure 5.7-(a); Table 5.2).
B. Monsoon
During present study it was found that, during morning hours of monsoon season,
Asian elephant utilized mostly the semi evergreen forest (27.25 %) habitat, followed by
utilization of moist mixed deciduous forest (23.75 %), tall grassland (20.25 %), wet
grassland (13.91 %), evergreen forest (11.38 %), miscellaneous (1.81 %) and least
utilization of Short grassland (1.65 %) habitat in Manas National Park (Figure 5.7-(b); Table
5.2).
During present study it was found that, during noon hours of monsoon season, Asian
elephant utilized mostly the semi evergreen forest (46.52 %), followed by utilization of
moist mixed deciduous forest (13.22 %), tall grassland (12.57 %), wet grassland (12.57 %),
evergreen forest (8.81 %), miscellaneous (3.97 %) and least utilization of short grassland
(2.34 %) habitat in Manas National Park (Figure 5.7-(b); Table 5.2).
During present study it was found that, during afternoon hours of monsoon season,
Asian elephant utilized mostly the moist mixed deciduous forest (27.66 %), followed by
utilization of semi evergreen forest (23.47 %), tall grassland (21.18 %), wet grassland (16.98
%), evergreen forest (5.43 %), short grassland (3.34 %) and least utilization of
miscellaneous (1.94 %) habitat in Manas National Park (Figure 5.7-(b); Table 5.2).
C. Retreating Monsoon
During present study it was found that, during morning hours of retreating monsoon
season, Asian elephant utilized mostly tall grassland (30.53 %), followed by utilization of
semi evergreen forest (22.34 %), wet grassland (22.24 %), moist mixed deciduous forest
(16.42 %), evergreen forest (3.84 %), short grassland (3.02 %) and least utilization of
miscellaneous (1.61 %) habitat in Manas National Park (Figure 5.7-(c); Table 5.2).
During present study it was found that, during noon hours of retreating monsoon
season, Asian elephant utilized mostly semi evergreen forest (44.02 %), followed by
utilization of wet grassland (19.26 %), moist mixed deciduous forest (12.09 %), tall
grassland (10.97 %), short grassland (6.83 %), miscellaneous (3.42 %) and least utilization
of evergreen forest (3.41 %) habitat in Manas National Park (Figure 5.7-(c); Table 5.2).
During present study it was found that, during afternoon hours of retreating monsoon
season, Asian elephant utilized mostly tall grassland (25.48 %), followed by utilization of
wet grassland (23.51 %), semi evergreen forest (23.23 %), moist mixed deciduous forest
(17.97 %), short grassland (6.01 %), evergreen forest (2.22 %) and least utilization of
miscellaneous (1.58 %) habitat in Manas National Park (Figure 5.7-(c); Table 5.2).
D. Winter
During present study it was found that, during morning hours of winter season, Asian
elephant utilized mostly semi evergreen forest (32.43 %), followed by utilization of moist
mixed deciduous forest (16.27 %), tall grassland (16.16 %), short grassland (13.55 %), wet
grassland (13.41 %), evergreen forest (6.7 %) and least utilization of miscellaneous (1.48 %)
habitat in Manas National Park (Figure 5.7-(d); Table 5.2).
During present study it was found that, during noon hours of winter season, Asian
elephant utilized mostly semi evergreen forest (23.36 %), followed by utilization of short
grassland (21.89 %), tall grassland (19.93 %), wet grassland (14.68 %), moist mixed
deciduous forest (12.04 %), evergreen forest (5.39 %) and least utilization of miscellaneous
(2.71 %) habitat in Manas National Park (Figure 5.7-(d); Table 5.2).
During present study it was found that, during noon hours of winter season, Asian
elephant utilized mostly semi evergreen forest (24.8 %), followed by utilization of tall
grassland (24.71 %), short grassland (20.39 %), wet grassland (17.16 %), moist mixed
deciduous Forest (9.73 %), evergreen forest (1.82 %) and least utilization miscellaneous
(1.39 %) habitat in Manas National Park (Figure 5.7-(d); Table 5.2).
Evergreen
Forest
Semievergreen
Forest
Mixed
Deciduous
Forest
22.01
29.01
Tall Grassland Wet Grassland
1.81
3.07
1.28
5.38
17
Morning ( 6 am- 10 am )
Noon ( 10 am- 2 pm)
Afternoon ( 2 pm- 6 pm)
13.17
11.99
31.73
15.74
16.13
10.28
7.07
34.31
33.62
17.83
22.4
2.97
2.11
1.09
Relative habitat utilization (%)
40
35
30
25
20
15
10
5
0
Short
Grassland
Miscellaneous
Habitats
Morning ( 6 am- 10 am )
Noon ( 10 am- 2 pm)
Afternoon ( 2 pm- 6 pm)
1.81
3.97
1.94
Tall Grassland Wet Grassland
Evergreen Semievergreen
Mixed
Forest
Forest
Deciduous
Forest
1.65
2.34
3.34
13.91
12.57
16.98
20.25
12.57
21.18
13.22
23.47
23.75
27.66
46.52
27.25
50
45
40
35
30
25
20
15
10
5
0
11.38
8.81
5.43
Relative habitat utilization (%)
(a) Pre-monsoon Season
Short
Grassland
Miscellaneous
Habitats
Evergreen
Forest
Semievergreen
Mixed
Forest
Deciduous
Forest
Tall Grassland Wet Grassland
Habitats
(b) Retreating Monsoon Season
Short
Grassland
1.61
3.42
1.58
3.02
6.83
6.01
22.24
19.26
23.51
25.48
30.53
10.97
16.42
12.09
17.97
23.23
44.02
22.34
Morning ( 6 am- 10 am )
Noon ( 10 am- 2 pm)
Afternoon ( 2 pm- 6 pm)
3.84
3.41
2.22
Relative habitat utilization (%)
(b) Monsoon season
50
45
40
35
30
25
20
15
10
5
0
Miscellaneous
20.39
21.89
1.48
2.71
1.39
5
13.55
15
13.41
14.68
17.16
20
16.16
19.93
24.71
25
16.27
12.04
9.73
32.43
23.36
24.8
30
6.7
5.39
1.82
Relative habitat utilization (%)
35
10
Morning ( 6 am- 10 am )
Noon ( 10 am- 2 pm)
Afternoon ( 2 pm- 6 pm)
0
Tall Grassland Wet Grassland
Evergreen Semievergreen
Mixed
Forest
Forest
Deciduous
Forest
Short
Grassland
Miscellaneous
Habitats
(d) Winter Season
Figure 5.7 Habitat utilization fluctuation during morning, noon, afternoon by Asian
elephant during (a) Pre-monsoon, (b) Monsoon (c) Retreating Monsoon and (d) Winter
Season in Manas National Park.
5.4.7 Correlation between fluctuation of habitat utilization of Asian elephant with the
fluctuation of temperature during different slots of day
Present study revealed that, with the fluctuation of daily temperature, humidity
during morning, noon, afternoon Asian elephant habitat utilization has positive correlation
during pre-monsoon (with temperature r=0.998, p=0.044, N=3; humidity r=0.999, p=0.033,
N=3), monsoon (with temperature r=0.546; humidity r=0.621), retreating monsoon (with
temperature r=0.987; humidity r=0.951) and winter (with temperature r=0.98; humidity
r=0.964) in short grassland habitat of Manas National Park (Table 5.1).
Table 5.1 Showing the Correlation between fluctuation of habitat utilization of Asian
Short grassland
Miscellaneous
Semi evergreen
Wet grassland
Temperature
-0.844
-0.932
-0.837
0.998 0.427
0.498
0.842
0.361
0.237
3
3
3
3
3
0.721
-0.229
0.853
0.926
0.827
0.487
0.853
0.35
0.247
0.369 0.033*
3
3
3
3
3
0.568
0.67
-0.584
-0.71
-0.141
0.546 0.809
0.615
0.532
0.603
0.497
0.91
0.632 0.401
3
3
3
3
3
0.642
-0.599
0.506
0.642
0.049
0.621 0.751
0.556
0.591
0.662
0.557
0.969
0.573
0.46
3
3
3
3
3
3
3
0.404
0.799
-0.591
-0.909
-0.56
0.987 0.768
0.735
0.41
0.597
0.273
0.621
0.102 0.442
0.38 0.044* 0.719
3
3
0.999 0.411
Correlation
Sig. (2-
0.73
tailed)
3
3
Correlation
Sig. (2tailed)
N
Pearson
Humidity
Tall grassland
Pearson
3
3
Correlation
Sig. (2tailed)
N
Temperature
0.245
tailed)
Pearson
Monsoon
Moist mixed
deciduous forest
Temperature
Sig. (2-
N
Retreating
Monsoon
0.709
Correlation
N
Humidity
Pre-monsoon
Pearson
Evergreen
Habitat
Climatic Factor
Correlations
elephant with the fluctuation of temperature during different slots of day.
Pearson
Correlation
Sig. (2tailed)
N
Humidity
Pearson
3
3
3
3
3
0.261
-0.881
0.707
0.962
0.68
0.951 0.856
Sig. (2-
0.832
0.313
0.5
0.176
0.524
0.199 0.345
3
3
3
3
3
0.405
0.64
-0.749
-0.513
-0.411
0.98 0.739
0.735
0.558
0.461
0.612
0.686
0.127 0.471
3
3
3
3
3
0.339
-0.584
0.7
0.573
0.474
0.964 0.785
0.78
0.603
0.507
0.657
0.731
0.172 0.425
3
3
3
3
3
tailed)
Temperature
Pearson
3
3
Correlation
Sig. (2tailed)
N
Pearson
Humidity
3
Correlation
N
Winter
3
3
3
Correlation
Sig. (2tailed)
N
3
3
* Correlation was significant at the 0.05 level (2-tailed).
Table 5.2 Showing fluctuation of habitat utilization by Asian elephant, temperature and
33.62
10.28
15.74 22.01 13.17 3.07 28.94 47
17.83
7.07
31.73 29.01 11.99 1.28 26.92 55.44
1.81 19.7
Temperature
5.38
Humidity
34.31 17
Miscellaneous
16.13
Short Grassland
Tall grassland
22.4
Wet grassland
Mixed Deciduous
Forest
Morning ( 6 2.97
am- 10 am )
Noon ( 10 2.11
am- 2 pm)
Afternoon ( 2 1.09
pm- 6 pm)
Semi evergreen
Forest
Season
Time
slots/Habitat
Pre-monsoon
Evergreen Forest
humidity during morning, noon and afternoon in Manas National Park.
88.67
Monsoon
Retreating
Monsoon
Winter
Morning ( 6 11.38 27.25
am- 10 am )
Noon ( 10
am- 2 pm)
Afternoon ( 2
pm- 6 pm)
Morning ( 6
am- 10 am )
Noon ( 10
am- 2 pm)
Afternoon ( 2
pm- 6 pm)
Morning ( 6
am- 10 am )
Noon ( 10
am- 2 pm)
Afternoon ( 2
pm- 6 pm)
23.75
20.25 13.91 1.65
1.81 26.12 92.6
8.81
46.52
13.22
12.57 12.57 2.34
3.97 31.19 68.27
5.43
23.47
27.66
21.18 16.98 3.34
1.94 29.36 75.01
3.84
22.34
16.42
30.53 22.24 3.02
1.61 23.41 89.8
3.41
44.02
12.09
10.97 19.26 6.83
3.42 30.44 55.83
2.22
23.23
17.97
25.48 23.51 6.01
1.58 27.89 72.68
6.7
32.43
16.27
16.16 13.41 13.55 1.48 13.4
5.39
23.36
12.04
19.93 14.68 21.89 2.71 24.63 39.77
1.82
24.8
9.73
24.71 17.16 20.39 1.39 20.53 62.96
94.03
5.4.8 Habitat Selectivity
Present study revealed that, Asian elephant has positive selection for the short
grassland (wi=2.96> 1), tall grassland (wi=1.26> 1), evergreen forest (wi=2.33> 1), semi
evergreen forest (wi=1.34> 1) and wet grassland (wi=2.31> 1); whereas Asian elephant used
the miscellaneous habitats proportionately with its availability (wi=1.03~ 1). However,
Asian elephant were found to have lesser selection for the moist mixed deciduous forest
(wi=0.7<1) (Table 5.3).
Table 5.3 Showing the habitat selectivity index of Asian elephant.
Habitat
Landscape
matrix
Evergreen Forest
Semi evergreen Forest
Moist Mixed Deciduous Forest
Tall Grassland
Wet Grassland
Short Grassland
Miscellaneous
2.51
28.1
26.7
22.32
11.4
3.67
5.31
Annual
habitat
Use
5.84
37.77
18.82
28.23
26.35
10.85
5.47
Selectivity
Index
2.33
1.34
0.7
1.26
2.31
2.96
1.03
5.5 Discussion
The Asian elephant utilizes the semi evergreen forest (28.33 %) mostly, though they
utilized the tall grassland (21.16 %), wet grassland (19.76 %) after semi evergreen forest in
Manas national Park. The Asian elephant in Manas National Park utilizes the semi evergreen
forest more than expected. The Asian elephant has utilized these habitats not based on
habitat availability but depending on the amount of food, shades (cover) and water
availability. The semi evergreen forest and the grasslands have closer approximation in
Manas National Park. Therefore, Asian elephant prefers these three habitats. These three
habitats, forms the highest edges in Manas National Park and in the edges the animal
activities are always more due to edge effect (Rabha, 2002). The landscape matrix of the
different types of habitat also showed highest area of the park has been covered by the semi
evergreen forest (28.1 %). But, it may not be the cause for high utilization of semi evergreen
forest habitat by Asian elephant. The semi evergreen forest provides shades and food, which
the elephant utilizes during the hot part of the day and feed on the grasses during the
morning and afternoon hours of the day. The Asian elephant in Manas National Park
maintains a relatively higher density in the jungle edge. It was also suggested by Olivier
(1978a), Rood, et al. (2010) and McKay (1973). The Asian elephant in Manas National Park
used the primary forest like semi evergreen forest, tall grasslands, wet grasslands which
contradicts the findings of Merz (1986) worked in Ivory Coast, showing that elephants use
secondary forest more intensively than primary.
The Asian elephant has tree main benefits from utilizing the forest edge viz. Firstly,
they are able feed on the grassland during morning and afternoon without getting too much
discomfort from rising temperature of sun during noon hours; secondly they are getting
access to the quality food of trees species and cover (shades) during noon hours in the
woodland habitat; thirdly they has greater safety in the woodlands and remaining in ecotone
will give them opportunity to get inside the woodland during any danger situation. McKay
(1973) also suggested the same except the third benefit.
The elephant is therefore strongly identified with a habitat that provides forest cover
and grassland in roughly equal proportions (Olivier, 1978a). Mueller-Dombois (1972) notes
that elephants make greater use of woody habitats where they occur in the form of smaller
stands and in combination with grass covered areas, with more continuous woody habitats
utilised to a lesser degree. As secondary re-growth is abundant in forest edges, are generally
rich in elephant foliage, which in return could benefit elephants living on the forest-nonforest interface (Sukumar, 1989b, 1990b; Zhang and Wang, 2003). Laws et al. (1975) using
faecal and track indices showed that, the majority of elephants that move from the grassland
remain in the forest edge, alternating between grassland and forest.
During the pre-monsoon season the Asian elephant utilizes the tall grassland (27.85
%) and semi evergreen habitat (27.81 %) mostly, which has been found more than expected
in MNP. During the pre monsoon season the grassland has been burned and new sprouts
comes out within 2-3 weeks, which attracts the herbivores including Asian elephant in MNP.
They graze on the new sprouts of the tall grassland during morning and afternoon hours and
they utilize the adjacent semi evergreen forest during the noon hours. Again, during the
monsoon, Asian elephant utilizes the semi evergreen forest (30.64 %) and the moist mixed
deciduous forest (21.23 %) mostly in MNP.
During the onset of the monsoon season, the tall grassland, wet grassland area
becomes dense and relatively become impenetrable compared to pre-monsoon season and
the grass becomes coarser along with the increasing number of insects disturbing elephants.
This makes elephant to move towards the northern part of the Manas National Park, where
habitats has been dominated by the semi evergreen, evergreen, moist mixed deciduous and
small patches of short grassland present sparsely between the woodlands. Inundations of the
habitats present in the southern part of the park during monsoon with the associated increase
of muddy area are also found to be the cause of northern movement of Asian elephant.
Presuming that, elephants feed more frequently on the bamboo (Dendrocalamus strictus)
during monsoon, it is apparent that, elephants were attracted towards the fresh growth of
bamboo at the onset of monsoon which has comparatively higher density in the northern part
of the Manas National Park. Elephants in Manas National Park were observed to occupy
northern part during monsoon season and shifted towards the southern and central part
during winter.
During retreating monsoon season, elephant utilizes the semi evergreen forest (28.48
%), tall grassland (22.44 %) and wet grassland (21.39 %) mostly. The onset of the retreating
monsoon season associated with the flowering of the grass species, which attracts the
elephant for moving down towards the grassland distributed on the middle and southern
portions of the Manas National Park. The elephant were seen feeding on the apical portion
of the pre-flowering stage grasses during the retreating monsoon season.
With the onset of the winter season, the grasses and plant starts drying and sheds
leaves respectively in Manas National Park, so, the availability of food for Asian elephant
becomes low. During this season, the availability of the water has been found uneven, as
water availability is more along the southern boundary line and northern boundary line
leaving the intermediate portion of the Manas National Park devoid of water excepting the
area closer to Beki, Hakua River. The elephant has been seen not preferring the water
sources in the southern boundary, as the area associated with anthropogenic disturbance and
cattle grazing. Hence, they need to move towards the northern boundary of Manas National
park, where they utilizes stream and ponds as the source of water. During winter season the
habitat utilization has been determined completely by availability of water in the habitat and
on the food. Hence, Asian elephant utilizes the semi evergreen forest (26.39 %), which are
present mostly along the northern boundary of the Manas National Park. Waterholes like
Dwlabill, Keshipukhri and other small water holes plays important role in supplying water to
Asian elephant in Manas National Park. Elephant distribution during the dry season in the
Kalahari sand region of Wankie National Park was determined primarily by the provision of
water supplies (Weir, 1971). A large mammal like the elephant could be expected to move
more considerable distances even with a short period and families of a clan seemed broadly
coordinated in their seasonal movement (Sukumar, 1989b). The reason for the elephant and
other animals’ migration is the high lands, continuous and uninterrupted hilly terrain for
grazing, assured food, ideal breeding ground and thick population (Singh, 1981).
During the present study this has been seen in Manas National Park that, daily
fluctuation of temperature and humidity plays major role in Asian elephant habitat
utilization pattern. Since, Asian elephant is black bodied animal and cannot remain for
longer duration as temperature rises during the day period. Hence, there has been fluctuation
in habitat utilization by Asian elephant in Manas National Park along with fluctuation of
temperature and humidity in the habitat. Asian elephant utilized more open canopied
habitats like wet grassland and tall grassland during the morning and afternoon period.
During the noon time the Asian elephant has been seen to utilize the closed canopied forest
at the edge of grassland such as semi evergreen, evergreen forest in Manas National Park.
These habitats are relatively cooler than the grassland habitat. Humidity has also correlation
with the fluctuation of habitat utilization by Asian elephant in different period of day but to
a lesser extent than the temperature fluctuation in Manas National Park. The elephant
utilized the lesser canopied habitat, when the temperature falls in Manas National Park.
The habitat specialists are more affected by area and isolation, while habitat
generalists more by landscape context. Here, in Manas National Park also Asian elephant
has daily movements to the forest inside the Bhutanese territory on a landscape basis.
Hence, extensive study on the habitat of Asian elephant in collaboration with Bhutanese
authority has been suggested for trans-boundary conservation strategy. There has been need
to maintain the connectivity of the habitats of Manas National Park with the habitats present
outside the eastern and western boundary by maintaining the existing corridor. Sukumar,
(2003) also suggested connecting the fragmented habitats by ensuring connectivity for
elephant movements and to expand elephant habitats to a reasonable size.
The international highway passing through the eastern boundary of Manas National
Park emerging as the major threat to the Asian elephant habitat contiguity. Because of the
construction of highway through the eastern boundary of Manas National Park, two
migratory routes have been impacted, which is permanent damage to the Asian elephant
seasonal movement towards the eastern boundary Subankhata Reserved Forest. Habitat
utilization pattern studies hence, important for conservation of Asian elephant in Manas
National Park on regular basis. Anon (1995) also suggested habitat-based ecological studies
of individual species as the basis for much successful conservation efforts.
PLATE 5.1 Asian elephant habitat in Manas National Park.
Evergreen forest habitat
Semi evergreen forest habitat
Moist mixed deciduous forest habitat
Tall grassland habitat
Wet grassland habitat
Short grassland habitat
PLATE 5.2 Habitat utilization patterns of Asian elephant in MNP.
Elephant herd utilizing the tall grassland habitat after annual burning in MNP.
Solitary elephant utilizing the short grassland habitat in MNP.