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WWF-INDIA
Testing of Early warning and Animal repellant
system ANIDERS
9/8/2017
2
Contents Testing of early warning system ................................................................................................................... 3
Introduction ............................................................................................................................................... 3
ANIDERS ................................................................................................................................................. 3
Methodology ............................................................................................................................................. 3
Findings .................................................................................................................................................... 4
Summary of animal visits ..................................................................................................................... 4
Reasons for failure to detect .................................................................................................................. 5
Animal –wise summary ........................................................................................................................ 7
Animal’s response to the system going off ........................................................................................... 8
Animal wise response ........................................................................................................................... 9
Issues of non-functionality .................................................................................................................. 16
Recommendations ................................................................................................................................... 17
3
Testing of early warning system
Introduction
Crop damage by herbivores is an enormous challenge in Uttarakhand. The State forest department’s
records from 2013- 15 show an average annual projected amount of Rs. 7116626 to be paid for incidents
of crop raiding by herbivores. The commonly used methods of mitigation and prevention of crop damage
include physical separation of conflicting species and resources or guarding of assets. The physical
separation is usually attempted through fencing/enclosing the resource in this case, crop fields,
repellants/deterrents and scaring devices to ward off animals or in some places fencing of the protected
areas. The guarding of assets on the other hand is carried out by using guarding and warning animals,
human guardians or use of physical devices on livestock. For guarding of crops, the farmers in India
usually watch the fields at night in make shift structures called machans, using noise through crackers or
other means to scare away an animal. Bigger farmers make use of tractors for the sound and light
especially for Elephants. The process is the basis of the technologies of early warning system being
developed in the country. The idea is to detect the presence of a herbivore before it enters the system and
then generate a response either in form of informing other farmers i.e. broadcast of detection or in the
form a visual or acoustic outcome that unnerves the animal and hence repels it away. Such technologies
are being trialed by WWF-India to find viable low cost solutions to address the issue. On such system has
been tested at the village Manaknthpur, near Terai West Forest division.
ANIDERS
The system under testing, known as ANIDERS(Animal Intrusion Detection and Repellant System) uses a
motion sensor to detect animals and generates response in the form of sound through a hooter and LED
light. Each sensor has a range of around 10-12 meters with a 180 degrees coverage and two units, one
having a single and the other a double sensor, were installed at the trial site. As the system functions on
motions sensors Wild boars and Chital are often detected from 12 m far and elephants due to their slower
pace are typically detected at 5 to 7 meters. Also the system has a larger range for detection of lateral
movement than animals moving directly towards it. Two units of this system were procured and installed.
Methodology
Camera traps (two for each unit) were deployed at the sites of installation of the two units. The number of
times an animal entered the range of the system (10-12m), the system’s response and animal’s response
were documented from the camera trap data for the period of January to April. As the range of camera
traps (15m) is more than the system, so all the camera trap captures weren’t recorded by the system. The
system and the camera traps were installed in the last week of December 2016.The camera traps have not
been removed since. The data from the last week of December has been included in January in this report.
The system was not functional for some of the nights during the period of study due to minor issues that
were repaired by the field staff. On one night the point person for the system in the village forgot to
switch it on. In case of Unit 2, on two nights system was tweaked to leave only the light on but that was
discontinued due to high animal movement. As a whole both units were considered not completely
functional for 5 nights each and the captures from those nights were excluded from the analysis.
The average time for which the system worked each day over these months: 12 hours
Switch on time: 1830 hrs-1900hrs
Switch off time: 0630hrs- 0700 hrs
4
Findings
Summary of animal visits
For the months of documentation, the total number of animal captures by the camera traps for both the
systems is 650, out of which 539 captures (83%) were recorded to be within the range (10-12m) of the
sensor(s) of ANIDERS. The system detected the animal 368 times resulting in alarm and LED of the
system going off. The animal was repelled for 86% (316) of these instances of detection. However the
instances when the animals appear to be crossing the system from left to right and not looking to enter the
system have been included under successful repulsion for the sake of analysis. Detail of such instances
has been given as an animal response category D, ‘Continues movements, unbothered’.
Figure 1 Overall Summary of animal captures within the range of ANIDERS
The month of March saw the highest number of animal visits and therefore captures. This can be
attributed to increased visit by elephants and chital for wheat crop.
Figure 2 Animal wise summary for Jan-April
650 539
368 316
Total captures Entry in system's range
Successful detection Successful repulsion
Overall Summary
No of camera trap captures
78
155
271
146
51
125
235
128
46
91
143
88
42
81
118
75
Jan Feb Mar April
Month-wise summary
Total captures Entry in system's range Successful detection Successful repulsion
5
Reasons for failure to detect
Out of 539 times the animal was observed in the range of the system, 171 times the system couldn’t
detect the animal owing to factors like, slow or negligible movement of animal and the animal moves
towards the system without any lateral movement of animal. For the ease of detection the motion of the
animal needs to be quick and sideways. An animal moving too slow or moving directly towards the
system is relatively difficult to detect unless it is as close as 5 m from the system. Over the time, animals
have been found to be trying to learn and adapt to the system.
Figure 3 Reasons for failed detection
81%
19%
Reasons for failed detection: Unit 1
Slow/Negligible Movement
Lack of lateral Movement
88%
12%
Reasons for failed detection: Unit 2
Slow/Negligible Movement
Lack of lateral Movement
6
The graphs below give the month wise break up of reasons for failed detection. From the graph Unit 2 can
be seen to have more failed detection due to slow/negligible movement; this can be attributed to the
location of the system. Though installed at a crucial entry point, there is a slope that animals have to
negotiate before coming in front of the system that more often leads to slowed down pace.
Figure 4 Reasons for failed detection over the months for Unit1
Figure 5 Reasons for failed detection over the months for Unit 2
0
20
40
60
80
100
120
January February March April
Fre
qu
en
cy
Unit 1
Reasons for system not going off over the months
Successful detections
Slow/Negligible Movement
Lack of lateral Movement
0
10
20
30
40
50
60
70
January February March April
Fre
qu
en
cy
Unit 2
Reasons for system not going off over the months
Successful detections
Slow/Negligible Movement
Lack of lateral Movement
7
Animal –wise summary
The graphs below depict the animal wise no of captures and response from system and animal. The
graphs show that Unit 1 faced more animal visits than unit 2 owing to the fact the unit 2 was placed
before a slope.
Figure 6 Animal-wise summary of captures for Unit 1
Figure 7 Animal-wise summary of captures for Unit 2
0
20
40
60
80
100
120
140
Unit-1
No of captures within the range
No of successful detections
No of repulsions
0
50
100
150
200
250
Unit-2
No of captures within the range
No of successful detections
No of repulsions
8
Animal’s response to the system going off
The total number of times either of the units went off
triggering the alarm and light to ward off the animal
is 368. Out of all these times, different animals
reacted in different ways over the months; therefore,
the response of the animal has been categorized into
the four categories. The graph below shows an
overall increase in captures and therefore responses of animals for the month of March. In some cases
animals were recorded to be trying to figure out how the system works by testing system’s response to
their small movements. The Fig 9 shows that overall, response category A, ‘frightened and runs away’
has been the most common response especially for Elephant and Chital.
Figure 8 Month-wise Animal response to both sound and light
Figure 9 Animal-wise Response to the system going off
0
10
20
30
40
50
60
70
Jan Feb Mar April
Animal responses over the months
A
B
C
D
0
20
40
60
80
100
120
Tiger Elephant Leopard Cheetal Sambar Wild boar Nilgai Porcupine Hare
Animal -wise response
A
B
C
D
Category Response
A Frightened and runs away
B Cautious and eventually walks
away
C Cautious but doesn’t walk away
D Continues movements, unbothered
9
Animal wise response
ELEPHANT
No Elephant captures were recorded for the month of January (and December last week). For months of
February and March, the animal entered the range around 85% of the times and was successfully detected
90-95% of the times. For February, the animal was repelled in 84% of these detections while that dropped
to 55% in the month of March. In April, the total captures dropped but the system fared well. Note: the
response category D in figure 11 is included as successful repulsion.
Figure 10 Month-wise Summary for Elephant
The most common response by the Elephant has been of the category A. The variation in the response
over the months can be seen in Fig 12.
Figure 11 Elephant responses to the system
The elephant movement started in February and the animal mostly responded as ‘frightened and runs
away’ in the first month. In the month of March, the animal was again repelled more often than not
(combining the responses in A and B), however the most common response as per the defined categories
has been C; ‘cautious but doesn’t walk away’. Most of these C category responses (8 of them) were of
0
21 23
7
0
19 22
7
0
16
12
6
January February March April
Month-wise summary: Elephant
No of Entries within the range Successful detection Successful repulsion
42%
23%
29%
6%
Elephant Responses
A B C D
Category A Frightened and runs away
Category B Cautious and eventually walks away
Category C Cautious but doesn’t walk away
Category D Continues movements, unbothered
10
this same individual Identified as E2 in Table 1. This elephant was reported, by villagers as well, to be
creating nuisance. In four instances during March, the individual E1 was documented outside the range
looking at the system and moving away without entering the range. This could also be because of the fact
that as the camera traps had a longer range and therefore their light went off before and the animal
responded to that. Elephants were found to be trying to learn about the system and modify behavior as
well. Some records in April show instances when the animal stayed longer than usual before finally
leaving, most likely trying to test and adapt to the system.
Figure 12 Elephant Responses to the system over the months
Identified individuals: Out of the total 61 captures of Elephants in both the Units, 24 captures have been
of two individuals (E1, E2). Four other captures of one of the identified individual (E1) and five captures
of the herd (EH1) are kept out of the analysis as the system wasn’t completely functional on those nights.
The elephant identified as E1 in Table 1, was documented in April; trying to test the system by moving
forward and back and then finally raiding the field irrespective of the alarm ringing.
Table 1 Identified elephants and captures
ID Description No of captures
EH1 (3
adults,
2 calves
)
One calf is of the height below the belly of the largest adult of the
herd .The other calf is little higher than the belly of the largest adult of
the herd. All individuals have tufted tails, except one who has hairless
tail
5 ( all in Feb) and system
wasn’t functional
E1 The tusker has been identified by his tusks that are curved inwards but
pointing outwards.
Unit 1: 7 (Feb-1,Mar-1, April-5)
Unit 2: 3 (Feb-2, Mar-1) ,4
times when alarm not functional
E2 The tusker is being recognized by his odd pair of tusks, ear marks
and tail. The left tusk of the animal is broken, only a small part of
which is remaining. The right tusk is present as a whole. The ears
(both) have tears and nicks all along lower edge after the ear fold. The
tail of the animal is a short one, cut or injured leaving only a small
part prominently visible.
Unit1: 13 ( All in march)
Unit 2: 1 ( March)
0
2
4
6
8
10
12
Jan Feb March April
Month-wise response to system: Elephant
A
B
C
D
11
CHITAL
The graph below indicates decline in rate of successful detection from 100% in Jan to 55% in March and
57% in April. The failure of detection is largely owing to slow/negligible movement of the animal. A
considerably part of which in the months of March and April indicates instances when the animal tried to
skip the alarm by standing still or moving slow, learning from similar experiences in the past when the
alarm stopped ringing because of no movement. Note: the response category D in figure 14 is included as
successful repulsion.
Figure 13 Month-wise summary for Chital
Figure 14 Chital responses to the system
15
70
172
77
15
48
95
44
15
41
82
35
Jan Feb Mar April
Month-wise summary:Chital
No of Entries within the range Successful detection Successful repulsion
48%
23%
15%
14%
Chital Responses
A B C D
Category A Frightened and runs away
Category B Cautious and eventually walks away
Category C Cautious but doesn’t walk away
Category D Continues movements, unbothered
12
The graph below shows that there is also a decline in the response A, ‘frightened and runs away’ in the
month of April.
This can be attributed to:
The times when the system was not functional in February, March and April, due to which they
exploited the possibility of browsing around the system.
The times when these animals moved cautiously or very slowly or stayed almost still and the
alarm stopped ringing immediately, due to which they started testing and trying the system’s
‘going off’ mechanism and sometimes stayed longer than usual before leaving.
Figure 15 Month-wise responses to system for Chital
0
10
20
30
40
50
60
Jan Feb March April
Month-wise animal response: Chital
A
B
C
D
13
SAMBAR
Sambar has visited system lesser number of times, as compared to Chital. Also a consistent increase in the
visits over the months can be seen, stating the preference for more mature wheat crop as forage. Even in
the month of April, Sambar captures did not decline considerably, unlike Chital or Elephant. The animal
has mostly escaped detection because of slow or negligible movement. Note: the response category D in
figure 17 is included as successful repulsion.
Figure 16 Month-wise summary for Sambar
Figure 17 Sambar responses to the system
5
14
23 23
5 5
16
21
5 5
14
18
January February March April
Month-wise summary:Sambar
No of Entries within the range Successful detection Successful repulsion
33%
45%
11%
11%
Sambar Responses
A B C D
Category A Frightened and runs away
Category B Cautious and eventually walks away
Category C Cautious but doesn’t walk away
Category D Continues movements, unbothered
14
The graph below shows that the animal hasn’t given the desired response in the start and the response B
,‘eventual walking away’ and A ‘frightened running away’ has seen a rise through the months but more so
for the response B.
Figure 18 Month-wise responses for Sambar
WILD BOAR
There is a consistent decline in the number of captures for Wild Boar over the months. This could indicate
to its preference for flowering/tillering stage of Wheat crop rather than the ripening stage. Note: the
response category D in figure 20 is included as successful repulsion.
Figure 19 Month-wise summary for Wild Boar
0
2
4
6
8
10
12
Jan Feb March April
Month-wise animal response:Sambar
A
B
C
D
14
16
9
4
16 16
8
4
16 16
8
4
Jan Feb Mar April
Month-wise summary: Wild Boar
entry detection repulsion
15
Figure 20 Wild boar responses
Figure 21 Month-wise wild boar responses
56%
5%
0%
39%
Wild Boar
A B C D
0
2
4
6
8
10
12
Jan Feb March April
Month-wise animal response: Wild Boar
A
B
C
D
Category A Frightened and runs away
Category B Cautious and eventually walks away
Category C Cautious but doesn’t walk away
Category D Continues movements, unbothered
16
Issues of non-functionality
Unit 1
Month Dates Reason Animal(s)
captured
Maximum
number of
individuals
captured at any
given instant
Number of
corresponding
captures
January - - - - -
February 1st-2
nd
February
Faulty
power
button
Elephant 5 6
15th-16
th
February
Light not
working
Chital 1 5
March 12th March Chital 1 1
15th March Chital, Hare 6 31
April 10th April Sambar 3 20
Unit 2
Month Dates Reason Animal(s)
captured
Maximum number
of individuals
captured at any
given instant
Number of
corresponding
captures
January 14th
January
Not switched
on
Wild Boar 1 1
February 12th
February
Chital, Sambar 5 86
March - - - -
April 8th-9
th
April
Chital, Sambar,
Wild Boar
6 86
17
Recommendations
The alarm should have multiple sounds, so that it takes longer for the animal to get used to it.
An external switch to adjust the duration of the alarm. If that's not feasible, an increase in the
duration from present would help. In some cases it was seen that the animal, especially chital,
tries to maneuver its way out using the time lags between two triggers.
The sensor's range is 10-12 m for lateral movement and if the animal walks directly towards the
system it reduces to 5-7 m. An improved sensor with a bigger range is required.
A switch for the LED and alarm separately, to document responses of animal to Light and sound
separately if required.
Automatic switch on of the system in the evening to make sure system doesn’t stay off in case
someone forgets to switch it on.
The wires inside the current systems got slightly rusted during rains. Improvement in design
further to protect from rains and use of better quality of components.
A viable low-cost mechanism of a combination such units is needed for large scale installations.
