CHAPTER 2 LITERATURE REVIEW -...
Transcript of CHAPTER 2 LITERATURE REVIEW -...
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CHAPTER 2
LITERATURE REVIEW
2.1 INTRODUCTION
In this chapter the previous methods and approaches implemented
to resolve the HEC have been presented. To secure the survival of the Asian
elephant, it is critical to obtain a more comprehensive understanding of the
raiding pattern. So far, several definite trends in HEC have been identified.
Elephant disturbance usually takes place in the forest border areas
between dusk and dawn and it is strongly seasonal, corresponding with crop
harvesting periods (Sukumar, 2003; Osborn & Hill, 2005). Moreover, conflict
is usually highest closer to protected areas that act as elephant refuges. HEC is
a complex problem, which cannot be mitigated through reliance on a single
mitigation technique. Each field site requires specific deterrence strategies.
Moreover, an extensive range of mitigation techniques has shown to be more
effective in driving away raiders. The practices employed by farmers to deter
elephants are also wide ranging. These generally include active traditional
deterrents such as shouting, drum beating, bursting firecrackers, torch
lighting, and setting fire to raw jute or tires fixed at the end of bamboo sticks.
Usually, farmers guard their crops on their own, however during peak raiding
season two to three neighboring farmers form groups to ride elephants back.
Additionally, forest department officials may aid in mitigating human-
elephant conflict by firing shots in the air as well as using domestic elephants
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to drive away crop raiders. In areas of high conflict cultivating alternative
crops to those preferred by elephants is practiced (Di Fonzo 2007).
2.2 HUMAN ELEPHANT CONFLICT MITIGATION
There are several projects and initiatives on the mitigation of
elephant human conflict taking place around the globe. Traditional methods
are devised by local communities and these include noise (shouting, beating
drums, burning bamboo, bursting fire crackers), light (fire at entry points to
fields, powerful spotlights) and missiles (stones, spears) (Lenin 2011).
Elephants are not easily visible in night time, hence the elephant
approaching the farm is identified at a later instant based on its sound or
movement nearby. Guarding and patrolling in the night time do not work
well. The inability of farmers to stay awake for several nights gives elephants
the opportunity to sneak into croplands. People endanger their lives by getting
too close to elephants or directly confronting them. Villagers have even given
up actively guarding their fields for fear of their lives. Elephant herds panic
when chased and damage more crops. Some commonly used methods such as
flaming arrowheads and spears, and homemade guns injure the elephants.
This work re-evaluates and refines some established mitigation
methods and introduces intelligent innovations as solution to HEC. The
evolution of the arsenal of HEC mitigation methods suggests that currently
relevant developments fall into two categories: traditional and intelligent.
Effective HEC mitigation is difficult to understand and problematic to
implement; it remains a complex package of measures that have to be used in
combination and flexibly, at different scales.
HEC mitigation division is between short-term methods
(traditional, disturbance, translocation and chili) and long-term ones
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(research, fencing, community conservation, land-use planning) (Hoare, R.
2012). People burst crackers and drove the elephants back in to the forest. Till
recently, the Coimbatore Forest Department had been using powerful
searchlights, crackers and drums to push the wild elephant herds back into the
jungle. The kumki (rescue) elephants were used more in hill areas to chase the
wild elephant herds into the forests.
Solutions to prevent HEC are divided into two types Traditional
solutions and intelligent solutions. The traditional solutions are categorized
based on biological considerations include bio fencing with vegetative barrier
and physical considerations include trenches, fencing, manmade structures
etc.
2.3 TRADITIONAL SOLUTIONS
2.3.1 Biological Considerations
As an alternative to electric fencing, low cost, sustainable bio-
fencing technology is used to protect elephants and humans. It is cultivation
of rows of Palmyra (Borassus flabellifer) palms in zigzag manner at the
territorial boundaries of elephants or around wild elephant affected farmlands.
Palmyra bio-fencing produces a sustainable solution for the human elephant
conflict by minimizing elephant and human deaths. In the long-run, it
produces additional tangible benefits that satisfy the needs of both human and
elephants. Palmyra bio fencing produces elephant feed also. The cost of
fencing is reduced by 8 times (cost per km. of electric fencing is Rs. 600,000
and cost per km. Palmyra fencing is only Rs. 72,000) with less maintenance
compared to electric fencing.
Vegetative Barrier: - In this type of barrier, thorny plants or other
plants which acts as repellent to elephants such as lemon trees, red chilli and
citronella grass can be sown around the bou9ndary of the protected area.
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Elephants, to some extent, avoid the place where this type of vegetation is
grown (Yaw & Lonneke 2008).
Trials with chilli based products have been conducted all around
the world (Alexandra Zimmermann, 2009 & Heges 2010). A comparative
study of the efficacy of chilli and tobacco-laced fence in various rainfall
regimes was conducted in forest villages of Hosur Forest Division (Tamil
Nadu), Wyanad Wildlife Sanctuary (Kerala) and Buxa Tiger Reserve (West
Bengal) in 2006. The results indicate that the fence is more effective in low
rainfall areas and in deterring elephant herds more than bulls. Applying
capsicum oleoresin in different forms like sprays and treated ropes which are
strung are used to prevent extensive damage to crops. Research has shown the
effectiveness of chili extracts as a spray to deter elephants during crop
raiding. When traditional measures are utilized, there is normally an
aggressive reaction from elephants, whereas in the case of aerial spraying of
capsicum oleoresin, the response by the elephants was more rapid and
resulted in prompt withdrawal from the crops without aggression (Osborn
2002). Capsicum oleoresin has thus far functioned as a viable short term
elephant repellent.
Acoustic deterrents are those that shock wildlife away by emitting
an unexpected loud noise or specific sounds known to scare wildlife.
Traditional acoustic methods are widely used by farmers throughout world,
mainly against elephants: such as beating drums, tins and trees; using whips
in addition to shouting, yelling and whistling; and setting off explosive
bombs, and homemade gunpowder (Yaw & Lonneke 2008). Disturbance
shooting gunshot over the heads of crop-raiding elephants has been a long-
standing deterrent, but it needs the intervention of animal control units or
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administration representatives. To scare baboons, the use of shots cannon
noise or predator sounds can be used. Disturbance shooting at roost sites is a
method easy to implement once all roost sites are known. However, baboons
may return to their roost sites once the disturbance ends.
Alarm systems established at the boundary of farms and set off by a
tripwire or set up directly on fences alert farmers about the presence of
elephants. Some more sophisticated techniques using tape recordings are
currently being tested in Kenya, where play-back of animal noise are used to
scare elephants. Researchers in Namibia have recorded elephant warning calls
and played these back to elephants in order to scare them away (Yaw &
Lonneke 2008).
Visual deterrents are a traditional method. The flames and smoke of
fires lit on the boundaries of fields or burning sticks carried by farmers can
deter wildlife. Burning tiers produce a lasting and noxious smoke which
affects both visual and olfactory senses, and increases the deterrent effect.
Tobacco is also efficient as a deterrent either in conjunction with chilli or
alone. Use of vehicle oil, ground chili and tobacco, smeared on ropes
surrounding fields prevents elephants from raiding crops.
Research work in Kenya on the use of African honey bees (Apis
mellifera) as a deterrent to crop-raiding elephants has been tested (King et. al
2009). The scheme uses beehives incorporated into a simple fence in such a
way that elephants contacting the barrier disturb the insects in their hives. The
fence design was proposed because playback experiments using the sound of
bees had previously caused elephant groups to either apparently retreat from
the source of sound or make alarm calls.
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Figure 2.1 Beehives Fencing
King et al (2009) presented the concept of using beehives to
mitigate elephant crop depredation. Beehut design the key element of the
and the connecting wire linking one beehive to the next with a gap of 7 m
hanging wire on the farm side of the beehut enables a strong piece of plain
wire to attach one beehive to the next beehive 10 m away as shown in Figure
2.1. Should an elephant attempt to enter the farm, he will instinctively try to
pass between the beehuts, and as the wire stretches, the pressure on the
beehives will cause them to swing erratically and, if occupied, release the
bees. The bees in turns disturbs the elephants and make it to move apart from
the area. Beehives along fences have reportedly been tried, but are of doubtful
efficacy as elephants usually raid at night when bees are inactive (Fernando et
al. 2008). Bees may also bite elephants and injure them making the elephants
react vibrantly.
2.3.2 Physical Considerations
Construction of elephant proof trenches is being done all over the
world. Trenches should be wide and deep enough to prevent elephants from
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crossing over it elephant proof trenches (EPT) are plagued by some of the
same shortcomings as electric fences. Elephants are known to kick the
unearthed spoil into the EPTs until they can cross it. Even trenches made to
specifications have been crossed by elephants. Commonly used dimensions
of trenches are 3m wide at the top, 1m wide at the bottom, and 2m deep as
shown in Figure 2.2. However, the dimensions vary from place to place
regions (Fernando et al. 2008). The main problem with trenches is erosion
and caving-in of the side walls which fills up the trench, enabling elephants to
cross it. The likelihood of erosion and caving-in depends on soil conditions
and rainfall. The sides of trenches can be stabilized with concrete, stones and
tar/asphalt, but this increases the cost significantly. They select a point; create
steps by kicking in the earth. EPTs are expensive to excavate, require regular
maintenance and are ineffective near streams. About half the crossing points
in EPT had been created by people. Elephant calves are known to fall into
trenches. They are unsuitable for sloping terrain, wet areas, or where soil is
prone to erosion.
Figure 2.2 Elephant Proof Trench
Trenches could be built around the boundaries of the protected
area after putting the vegetative barrier. This would further prevent the
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elephants crossing the boundary. (Trench specification-Top width = 2.10 mt;
Bottom width = 1.20 mt; Depth = 2.40 mt.). The dugout earth is to be used as
mound towards the inner-side of the protected area.
During our investigation, all the forest ranges of the Coimbatore
Forest Division were covered to address the human-elephant conflict. The
Coimbatore Forest Division falls under the Elephant Reserve No. 8, in which
Nilambur-Silent Valley of Kerala forms the major portion of the tract and the
division is included in the Project Elephant Perspective Plan of the Tamil
Nadu State Forest Department. Elaborating on the measures taken so far more
than 210 km of elephant-proof trenches have been dug in Coimbatore
division. This had helped in preventing elephants from venturing out of
Department had prepared.
Extensive experimentation with elephant fencing showed that
elephant fencing could be broadly classified into five types, (Hoare, R. 2012).
Model 1. Extended full barrier fence (long, often separating land uses like
national parks from agriculture)
Model 2. Partial interface fence (open-ended but incorporating natural
barriers, e.g. escarpment, lake)
Model 3. Community protection fence (encircling a whole village with crops
and facilities)
Model 4. Household ownership fence (encircling dwelling and crops of one
household)
Model 5. Crop protection fence (encircling only small crop-growing areas)
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In all five fence models, monitoring has shown that the deficiencies
of detailed and regular maintenance inevitably manifest themselves and make
it impossible for ordinary or electric fencing to withstand the challenge.
Farmers can protect their small lands from problematic elephants with simple
single- or double strand electric fencing if they can get small amounts of
initial capital finance or aid, and if they maintain their own encircling fences.
A combination of simple electric fence and chilli deterrent methods, using
low specification temporary string fences, would constitute a back-up system
almost guaranteeing freedom from elephant crop raids (Hoare 2012).
Electrified fences are commonly employed by individuals and
private companies to protect farm lands from elephants and by governments
and conservation agencies to restrict elephants to particular areas. If
maintained properly it can be the most successful barrier against elephant
depredation. Electric fences carry a high voltage at low amperage as a pulsed
current. They do not cause physical harm to elephants but gives a powerful
and unpleasant electric shock upon contact. Since an electric shock is
presumably very different to any stimulus an animal would encounter
naturally, so they tend to be very wary of it and not to adapt to it easily.
However, some elephants eventually adapt with prolonged exposure.
Elephants have been known to breach electric fences by using tusks
which do not conduct electricity, pushing or kicking down fence posts and
stepping over the fence using the thick soles of their feet to depress the wires.
Some elephants also learn that an electric shock does not harm them and
simply barge through the wires. Once an elephant learns to breach an electric
fence, the fence becomes useless against the particular individual. Therefore,
the most important aspect of a psychological barrier such as an electric fence
is to discourage elephants from initially challenging it. This can be enhanced
by making it more visible and obvious, keeping it fully functional, and
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through judicious, strategic placement. Fences erected along the ecological
boundary between elephant habitat and human areas (edge of permanent
human settlements and cultivations), tend to be more effective because
maintenance is easier due to better access and less likelihood of challenges by
elephants. Fences within forest areas tend to be less effective and not lasting
due to logistical difficulties in maintenance. In addition, due to the reduced
human presence in forests, elephants are more likely to spend longer time
testing and challenging the fences (Hoare 2012).
Fernando et al (2008) discussed electric solar fencing to avoid
elephant-human conflict. Electric fences are seen by local people as a
permanent solution and there is a temptation to install fences wherever there
is conflict as shown in Figure 2.3. They are expensive to install, require
constant and high maintenance. There is a high rate of failure of electric
fences. These fences are even broken by elephants using tree woods. Fences
that illegally tap into mains AC power supply have killed crop raiding
elephants and also humans. Electric fences are considered effective in
reducing crop raiding (Kioko 2008), literature on the use of electric fencing
to manage crop-raiding by elephants suggest that a number of factors
including fence design, voltage, maintenance, elephant pressure and behaviour
may influence their success . Considering the high installation and maintenance
cost of electric fencing, there is a need for more research to establish the
factors that determine the effectiveness of electric fences in deterring
elephant crop-raiding.
Nearly 1,700 km of solar fences erected in Tamil Nadu, including
100 km in the Coimbatore division, were required constant maintenance and
the results had been mixed. 81 people killed by elephants in Coimbatore
Forest Division from 2000 to 2011. In 2012, wild elephants had ventured into
human habitations more than 3,000 times in this division.
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Figure 2.3 Electric Fencing
Singh & Chalisgaonkar (2006) have discussed how railway lines,
highways, irrigation and hydroelectric canals, industrial establishments and
human settlements along the migration corridors have affected the migratory
movement of the elephants. The report suggests the alternatives and
modifications in the manmade (Civil Engineering) structures to facilitate the
movement of Elephants, save this endangered species from extinction and
avoid the animal-human conflict in the Rajaji Corbett Elephant Range. The
Coimbatore Forest Department has established 32 waterholes in the forest
areas. As many as 250 field staff and 120 anti-poaching watchers work
almost round the year to drive elephants back into forests.
In (Loarie et al 2009) discussed about the role of the artificial
water sources and food which allow elephants to reside in forest during dry
seasons. Planting food trees in elephant habitat and corridors to augment
resources available to elephants has been a good method. Regeneration of
bamboo along stream courses and cultivates
sugarcanes could be practiced. It is not practical to grow such crops and trees
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over large areas and its long term effectiveness is limited. Elephants are
known to eat up to 400 different species of plants and require up to 200 kg of
forage a day per animal. Therefore, to restock an area with even a fraction of
these species would be a challenging task. Elephant distribution is influenced
by the presence of surface water and rivers, and it has been suggested that
manipulating water sources could influence elephant presence. Water
provisioning may render previously unused habitat attractive, resulting in
redistribution of elephants. It may also lead to an increase in population and
density of elephants in that area which may affect the quality of the forest
vegetation and dramatically impact the biodiversity of the surrounding area.
2.4 INTELLIGENT SOLUTIONS
Wood et al (2005) Large mammal populations are difficult to
census and monitor in remote areas. A new detection technique that relies on
sensing the footfalls of large mammals is proposed. A single geophone was
used to record the footfalls of elephants and other large mammal species at a
waterhole in Etosha National Park, Namibia. They were able to discriminate
between species using the spectral content of their footfalls with an 82%
accuracy rate. This could be improved upon by using an array of geophones.
Graham et al (2012) have discussed the use of mobile phone
communication in effective human elephant conflict management in Laikipia
County, Kenya. Early warning of crop raiding has been identified as an
important element in successful deterrence of elephant crop raids. Therefore
the effectiveness and timeliness of communication among farmers and
between farmers and wildlife management authorities could be critical for
successful management of human elephant conflict. Effective communication
among rural resource users and between communities and outside agents is
important in the creation of social capital and in the creation of trust between
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conservationists and resource users. However, such communications can be
fraught with misunderstanding, suspicion and delay.
Wijesinghe et al (2013) have presented the design and
implementation of an intrusion detection and alerting mechanism (eleAlert)
for fences separating wildlife habitats and human settlements. An eleAlert is
generated by a network of sensors to detect and locate damages instantly, and
alert communities under threat via mobile communications network. Electric
fences are harmful to elephants. There are cases of elephants being killed due
to the large current passing through the fences. In turn, human deaths also
occur due to such electric fences.
In Venkataraman et al 2005) discussed the potential use of satellite
technology for conflict mitigation. The elephant GPS radio collar transmits
the geo locations to the satellite to monitor the movement of the herds in the
forest regions. There have been attempts to track elephants using satellite
movements, it is possible to predict if the animals are headed towards a
village and provide the inhabitants with advance information. But to be
relevant and timely, data needs to be updated more than once every 24 hours
(Venkataraman et al 2005). The high cost of the equipment limits its use to no
more than a small number of animals (Fernando et al 2008). The elephants
tagged with radio collars react violently and damage it. A 20-year-old male
elephant that was shot with a tranquilized dart by Forest and WWF experts for
fixing the radio collar. The elephant's carcass was traced by officials at the
foot of the Anubavi Subramaniar Koil hills near Thadagam, 22 km west of
Coimbatore. The elephant collapsed in an uncomfortable position when
sedation had reached its peak and this may have caused respiratory problems
which led to its death. The elephant connected with radio collar is shown in
Figure 2.4.
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Figure 2.4 Elephant Radio collar
Juang et al (2002) discussed about the design tradeoffs and early
experience in building sensor networks for position tracking of wild life.
These sensor networks described are to be laid above the ground level and
work well when line of sight exists. But often the sensor nodes are destroyed
by the elephants. Farmers and wood pickers may also disturb the sensor nodes
as they are unaware of the importance of these devices.
Venter & Hanekom 2010) proposed possibility of using the
elephant-elephant communication (elephant rumbles) to detect the presence of
a herd of elephants in close proximity, In this work the authors have recorded
the low frequency infrasound but they do not compare with other animal
infrasound pattern and confirm it is an elephant occurrence. Results obtained
suggest that the algorithm can reliably detect elephant vocalisations from
noisy recordings as long as the harmonic structure of vocalizations is not
buried in background noise.
In (Seneviratne et al 2004) the authors discuss the design and
implementation of an electronic sensor and analysis system for the detection
of Infra-sound elephant calls. The proposed electronic system will contain
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sensors to detect Infra-sound calls, Signal Processing devices and also
automatic deterrence systems for persuading rogue elephants to move away
from protected areas. Isolating and selectively enhancing Infrasound signals
in highly noisy environments is a challenge and the noise may be from
uncorrelated sources as well as highly correlated sources such as a multitude
of insect noise as well as larger animals like frogs, birds, aquatic life, human
voices and vehicle noise.
Vermeulen et al (2013) proposed an Unmanned Aircraft System to
survey elephants, the elephant. The images are acquired at a height of 100 m
but it possess a small flight time of 45 min, the distance covered by is 40 km,
expensive and not autonomous.
Dabarera & Rodrigo (2010) proposed appearance based recognition
algorithms for identification of elephant. Given the frontal face image of an
elephant, the system searches the individual elephant using vision algorithms
and gives the result as, already identified elephant, or as a new identification.
The accuracy of this system is affected by the low quality of the images, the
strange poses of the head positions of the elephant and high illumination
variances. The system is also a semi-automated mechanism for elephant
tracking. Head position of elephant cannot be captured at a proper angle.
Ardovini et al (2008) present an elephant photo identification
system based on the shape comparison of the nicks characterizing the
is used by the system as a basis for a set of
segmentation and normalization hypotheses aimed at comparing a query
photo Q with different photos of the system database possibly representing
the same individual as Q. The proposed shape comparison method is based on
matching multiple, non-connected curves. The borde
profile extracted using a common edge detector is very hardly completely
connected and it is sometimes partially occluded by other elephants or trees.
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Goswami et al (2011) addressed the process of identifying
elephants from photographs, and comparing resultant capture recapture based
population parameter estimates using supervised visual identification of
individual variations in tusk, ear fold and lobe shape. The authors show that
this is a reliable technique for individual identification and subsequent
front image is not possible.
In Walas et al (2008) the authors discussed a multi-layered drive
control for walking robot. This was implemented by using six-legged robot
with 18 DOF. Each leg uses 3 DOF. Each joint used one DC-servomotor and
synchronization was done among the legs using master slave concept. The
authors also addressed sensing system issues for walking robot using closed
control loops through these sensors. However the main problem is to
coordinate 18 joints while walking with particular gait. The problem was
solved by designing dedicated distributed control architecture.
In Amaral et al (2010), the authors designed a robot that walked on
straight, curved paths, detecting and overcoming known obstacles. Obstacle
overcoming is done using information from contact sensors installed on the
robot feet. Complex movements and tracking sequences are proposed to be
built from a small group of simple movements sequenced according to the
contact key switching sequence. Leg cooperative movements that move the
robot are synchronized through a gait matrix and an addressing algorithm that
moves the robot body laterally during straight or curved walking trajectories.
In Szrek & Wójtowicz 2010) the authors discussed about the
construction of the LegVan wheel-legged robot with an autonomous leveling
and obstacle detection system.
suspension system, general operation strategy and control system. The wheel-
legged robot has been designed mainly to operate in an uneven terrain and to
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be able to overpass obstacles by walking. The robot has one central control
computer and several local autonomous controllers. The central computer is
located on the robot and it wirelessly communicates with a remote control
computer (the user). The local systems are responsible for the execution of the
desired robot motions and for taking all the measurements.
In Raibert et al (2008) the authors developed a new breed of rough-
terrain robots called BigDog that captured the mobility, autonomy and speed
of living creatures. Such robots could travel in outdoor rough terrains which
are difficult to travel for conventional robot vehicle platforms. BigDog has
about 50 sensors. Inertial sensors measure the attitude and acceleration of the
body, while joint sensors measure motion and force of the actuators working
at the joints. The onboard computer integrates information from these sensors
to provide estimates of how BigDog is moving in space. Other sensors
monitor BigDog's homeostasis: hydraulic pressure, flow and temperature,
engine speed and temperature, and the like. The onboard computer performs
both low-level and high level control functions. The low-level control system
servos control the positions and forces at the joints. The high-level control
system coordinates behavior of the legs to regulate the velocity, attitude and
altitude of the body during locomotion. The control system also regulates
ground interaction forces to maintain support, propulsion and traction.
2.5 NEED FOR EARLY WARNING SYSTEM
It is easier to chase elephants before they enter fields and therefore,
most damage can be averted (Sitati et al 2005). Guarding from watch towers,
patrolling and trip wire alarms provide farmers with advance warning of
approaching elephants. Once the animals are detected, active crop guarding
devices using light and noise are deployed to chase them away. This is
because once elephants enter a cultivated field they cause significant damage
and can be difficult to drive away, even using novel active deterrents
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An early warning system to minimize the human elephant conflict
in the forest border areas is proposed in this article. The system helps mitigate
such conflicts in two ways:
(1) Provides warning to people about the anticipated entry of
elephants into human habitation.
(2) Provides advance information to the authorities to take action
to chase the pachyderms back to the forest.
An early warning system is proposed in this work to detect the
movement of elephants in the forest border areas. An analytical procedure is
developed to study the behavior of elephants taking migration data into
consideration using a three-state Markov chain. Hardware module for
elephant intrusion detection system is designed to monitor the elephant
movement into the human habitation and sending early warning through short
messaging service (SMS) to the forest officials to take necessary action.
In this work, a four-legged and wheeled robot, namely the Wheeled
Quadruped Robot is developed specially to move in any terrain i.e. both walk
using legs and move on wheels. The robot proposed is used in detecting
elephants in forest border areas only, not inside the forest. The robot can be
laid in certain elephant pockets through which the elephants normally come
out of the forest and enter human habitation. The Quadruped Robot is made to
move in a predetermined path to capture the elephant image in and around
these pockets.
An early warning system to minimize the human elephant conflict
in the forest border areas using image processing is developed in this work.
The system helps to detect the elephants even in the presence of other wild
animals like Bison, Tiger, and Deer etc. The system also identifies the
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elephants coming in groups. The reliability of elephant detection is tested and
the time to detect the elephant images is optimized with the proposed
optimized distance metric.
Elephants are the largest terrestrial mammals which uses infrasonic
vocalization to communicate over short and long distances (Venter &
Hanekom 2010). A recording of elephant vocal communication is used in this
work to determine whether the signal represents an elephant sound or not. The
system consists of a FM transmitter and receiver, an amplifier, and an audio
jack connected to a PC to record and analyze. When the sound of an elephant
crosses a threshold an SMS is sent to the forest officials.
2.6 CONCLUSION
The literature review presented contributes to analysis of HEC
patterns. The principal mitigation traditional techniques are not very efficient
indicating that there is much scope for trying out simple, low-cost active
deterrence methods with early warning. The mitigation strategies provide
viable solutions for human elephant conflict. The effectiveness of the
mitigation techniques and livelihood strategies helps in conserving both
humans and elephants. Human-elephant conflict has taken place since the
advent of agriculture, and will carry on if our burgeoning human population
continues to encroach upon natural habitat. For the conservation of the Asian
elephant it is imperative that researchers continue investigating correlates of
elephant damage so as to improve present relations as well as prevent conflict
from occurring in the future. The HEC strategy improves elephant habitat,
and aid communities in generating income from the forest by harvesting
certain plants in a sustainable manner.