A Suggested

Protocol for

Radio-Telemetry

Studies on Tiger

(Panthera tigris L.)

By

Dr Aniruddha

Majumder

&

Mr S.P. Yadav

2014

1

A Suggested Protocol for Radio-Telemetry studies on

tiger (Panthera tigris L.)

1. INTRODUCTION

Tiger (Panthera tigris L.) is the largest of all the felids found in diverse habitat types and show

remarkable tolerance to variation in altitude, temperature and rainfall regimes (Sunquist et al.

1999). They can potentially hunt prey varying from small mammals to large bovids (Sunquist

1981; Majumder et al. 2013). They are territorial and wide ranging and the effective size of the

territory is a function of density and biomass of prey species in its habitat (Smith et al. 1987a;

Smith et al. 1987b; Majumder et al. 2012). Therefore studies undertaken to address these issues

on tiger are important because it can provide a better insight of tiger ecology and behavior.

Radio-telemetry is such a method that has been effectively used to address these questions

(Quigley et al. 1989; Smith et al. 1987a; Sunquist 2010; Barlow et al. 2010; Goodrich et al.

2010; Sharma et al. 2010; Majumder et al. 2012).

Radio-tracking is the technique of determining information about an animal through the use of

radio signals from or to a device carried by the animal and the first functional telemetry system

created by Cochran and Lord (1963). “Telemetry” is the transmission of information through the

atmosphere usually by radio waves, so radio-tracking involves telemetry, and there is much

overlap between the two concepts (Mech and Barber 2002). The basic components of a radio-

tracking system are (1) a transmitting subsystem consisting of a radio transmitter, a power source

and a propagating antenna, and (2) a receiving subsystem including a “pick-up” antenna, a signal

receiver with reception indicator (speaker and/or display) and a power source. Most radio

tracking systems involve transmitters tuned to different frequencies (analogous to different

AM/FM radio stations) that allow individual identification.

Three distinct types of radio-tracking are mainly in use today: (1) Very High Frequency (VHF)

radio tracking, (2) satellite tracking, and (3) Global Positioning System (GPS) tracking (Mech

and Barber 2002).

VHF radio-tracking is the standard technique in use since 1963. An animal wearing a VHF

transmitter can be tracked by a person on the ground or in the air with a special receiver and

directional antenna. Briefly, the advantages of VHF tracking are relatively low cost, reasonable

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accuracy for most purposes, and long life; disadvantages are that it is labor-intensive and can be

weather-dependent if aircraft-based. Nevertheless, VHF radio-tracking is by far the most useful

and versatile type of radio-tracking, for not only does it yield location data, but it also allows

investigators to gather a variety of other types of information (Mech 1974, 1980, 1983).

Satellite tracking employs a much higher-powered transmitter attached to an animal. The signal

is received by satellites and the animal‟s calculated location is sent to a researcher‟s computer.

Satellite tracking requires a much higher initial cost and is much less accurate (mean accuracy =

480 meters [Fancy et al. 1989]) and, for most species, is shorter-lived than VHF systems.

If only animal locations and gross movements are of interest to a study, such as a dispersal path,

satellite tracking is advantageous because it requires no personnel in the field once the tracking

device is placed on the animal. It is especially useful for monitoring long-range movements.

However, most wildlife studies also require a variety of other information that satellite tracking

does not provide, including number of companions, individual productivity, behavior, and

population size and trend. For carnivores, information about predatory habits, such as rates,

location, species, age, sex, and condition of their kills, cannot be obtained by satellite tracking.

GPS tracking of animals is the latest major development in wildlife telemetry. It uses a GPS

receiver in an animal collar to calculate and record the animal‟s location, time, and date at

programmed intervals, based on signals received from a special set of satellites. GPS tracking is

based on a radio receiver (rather than a transmitter) in an animal‟s collar. The receiver picks up

signals from a special set of satellites and uses an attached computer to calculate and store the

animal‟s locations periodically (e.g. once/15 minutes, once per hour, etc.). Depending on collar

weight, some GPS collars store the data and drop off the animal when expired to allow data

retrieval; others transmit the data to another set of satellites that relay it to the researchers; and

still others send the data on a programmed schedule (e.g., daily) to biologists who must be in the

field to receive them. GPS tracking also has high initial costs and at present is relatively short-

lived and applicable to mammals the size of a wolf or larger, or to birds on which solar cells can

be used. GPS tracking is highly accurate and especially suited to studies where intensive and

frequent data many locations/day) are needed or useful. Depending on several variables, GPS

tracking may or may not require frequent field visits (Mech and Barber 2002).

Though in recent days, radio-collared with inbuilt cameras have been used in various studies, it

is not suggested in case of tiger, as it is too bulky with too short a battery life to justify the whole

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effort and risk associated with this type of collar (Kaustubh Sharma pers comms). However, the

pace at this technology is developing and will soon become practical.

Along with knowledge on various tools used for radio-telemetry study, it is also important to

have practical understanding while handling an immobilized tiger at the time of fitting radio

collar. The Global Tiger Forum (GTF)-mandated to conserve tiger in the wild, had compared

various literatures on radio-telemetry studies and suggested a Protocol on Radio-Telemetry

studies on tiger for manager and biologists of Tiger Range Countries (TRCs). This will help to

augment the domain knowledge on the tools and technologies used for radio-telemetry studies on

tiger and can be also used by TRCs to study ecological and management studies of tiger

movement, behavior, habitat use, survival, and productivity assessments.

2. METHODS

2.1. Details of various tools used for radio-telemetry studies on tiger

2.1.1. Transmitter unit or radio-collar- According to Habib et al. (2010), the radio-collars

used in Indian Sub-continent on tiger have been classified into following categories

1a 1b

Fig 1a and 1b. Telonics™ VHF collar with dipole antenna and a tiger with VHF radio collar

I. Conventional Very High Frequency (VHF) - Very High Frequency (VHF) technology

was the earliest modality used for tracking and identifying individual wild animals

electronically. The first successfully tested system was demonstrated in 1963 (Cochran

and Lord 1963). A VHF tracking system consists of two components – the transmitter

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(mounted on the animal) and the remote receiver. Depending on which country they are

used in, VHF transmitter tags use different frequency ranges. Common bands are 148 –

152 MHz, 163 – 165 MHz, and 216 – 220 MHz, although frequencies can range from 27

MHz to 401 MHz (Mech and Barber 2002). Lower frequencies require long antennas (for

example, a quarter wave whip at 148 MHz needs to be 50 cm long) which are often

impossible to place on smaller animals. Higher frequencies, although requiring a shorter

antenna, suffer more from „signal bounce‟ due to more pronounced multipath effects

from the environment, affecting their useful detection distance (Cederlund et al. 1979).

Transmitter power varies according to the requirements of the study, but is generally

between -10 dBm and +10 dBm (Markham 2004, http://www.sirtrack.com/,

http://www.biotrack.co.uk/).

VHF collar with mortality censor may monitor discovers a faster radio pulse if animal has

not moved for more than 4 hours.

II. GPS collars with an Argos uplink- Fully satellite collar devoid of download facility or

GSM facility. Satellite shall communicate with collar and data can be downloaded using

Argos uplink (Fig 2).

Fig 2. GPS collar with Argos uplink Fig 3. GPS collar with Iridium uplink

III. GPS collars with an Iridium uplink- This is also a fully satellite collar devoid of

download facility or GSM facility. Satellite shall communicate with collar and data can

be downloaded using Iridium uplink (Fig 3).

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IV. GPS collars with a ground download utility via VHF or Ultra High Frequency (UHF) -

Existing GPS enabled wildlife tracking devices acquire fixes at constant time intervals

(for example, every 15 minutes (www.lotek.com, Markham 2004) in order to reduce the

power consumption of the tracking device and prolong its life For this purpose the animal

need to be at close distance. Example of a GPS-VHF collar is Habit collar (Fig 5) and

example of a GPS-UHF collar is Lotek or Vectronic one.

Fig 5. GPS-VHF collar fitted Fig 6. GPS-GSM collar

V. GPS collars with GSM download- It provide control over the schedule of fixes since

commands can be sent and received via short message services (SMS) using GSM

technologies (Habib et al. 2010). Collar (Fig 6) send GPS locations via GSM mobile

phone coverage, or remotely downloaded with a handheld UHF device (Fig 5). GSM

mobile phone network facilitates the communication between collar and receiver. Visual

mapping data available via Google Earth.

Weight of a collar: A „rule of thumb‟ has been proposed stating that the weight of the tracking

device should not exceed 5% of the host‟s bodyweight in order to avoid detrimental effects to

behavior (Cochran 1980; Aldridge and Brigham 1988). In Pench Tiger Reserve, Majumder et al.

(2012) used Telonics TM

and Vectronics™ radio collars, weighed less than 1% of the body

weight of the tigers. Example- If a tiger body weight is 200 kg then the collar weight can be 2 kg.

Telonics TM

VHF collars are generally lighter in weight and range 600 gm to 1500 gm whereas

Vectronics™ satellite collar weighed 2-2.5 kg. The small cubs can be fitted with temporary

collars and subsequently re-collar with permanent collar.

Cost of Radio Collar and its manufacturer

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VHF collars are comparatively cheap and price ranged between $1000--$1500 whereas satellite

telemetry can be viewed either as costly or economical. The cost of a single PTT unit is usually

$3,000-$4,500, some 10-20 times as high as that for a conventional VHF transmitter (White and

Garrott 1990). (If the PTT can be retrieved, refurbishment costs $150-$300). Additionally, the

researcher must pay for the data acquisition and processing which can cost $90-260 per month

per animal (Wilson et al. 1992).

Some important companies manufacturing radio-collars for tiger are

1. http://www.telonics.com/

2. http://www.vectronic-aerospace.com

3. http://www.lotek.com

4. http://www.biotrack.co.uk/

2.1.2. Receiver Unit

Receiving systems detect and identify signals from transmitters. A basic receiving system

consists of a battery-powered receiver, a receiving antenna, cables, a mechanical or human

recorder, and a human interpreter with accessories such as a speaker or headphones (useful for

reducing external noise when detecting the transmitted signal, Mech 1983; Samuel and Fuller

1996).

Fig. 7. Various receivers and external cord

I. Receivers: Receivers (Fig 7) must be able to detect and distinguish signals of specific

frequencies. Standard receiver controls include a three-position power switch (internal or

external power and off), dials for gain and channel, band, and fine frequency adjustments,

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jacks for an external antenna (UHF or BNC), headphones, a recorder, and external power.

Some receivers also have a volume control. Volume differs from gain in that an increase in

gain increases signal sensitivity (up to a point beyond which the sensitivity does not increase)

whereas increasing volume affords no greater signal sensitivity (Mech 1983).

Some receivers require frequencies to be entered by dials while others are digitally

programmable. Many receivers also include two needle gauges; one indicates remaining

battery power and the other the strength of the signal received. The latter can be especially

useful in aerial tracking where the signal strength changes rapidly (Mech 1983). Most

portable receivers are powered by standard alkaline batteries (i.e. 8 AA, 1.5 V penlight cells)

(Cederlund et al. 1979) and will function for 8-12 hours. (With rechargeable batteries, the unit

functions 5-8 hours [Samuel and Fuller 1996].) Generally, receiving units can also be

powered externally from vehicle cigarette lighters or separate larger batteries such as

motorcycle or marine batteries.

8a 8b 8c

Fig 8a, 8b and 8c Di-pole antenna and mortality censor, Yagi type and H-type antenna

II. Antenna: Frequency determines the size of receiving antennas. In general, the higher the

frequency, the smaller the antenna.

The simplest kind of receiving antenna is a straight wire or “dipole” (one half the wavelength of

the transmitted frequency) attached to the receiver‟s antenna jack (Fig 8a). Dipole antennas are

omni-directional and therefore, are most appropriate for presence /absence studies (Mech 1983).

These antennas are often used at a stationary reception site in an automatic tracking system or as

part of a portable unit mounted on vehicles (see Mounting Antennas).

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Loop antennas can be a circle, an oval, or diamond-shaped, with, like other antennas, dimensions

dictated by the signal frequency. Loop antennas are especially useful for minimizing the size of

lower-frequency antennas so they can be used as hand-held portable units (Cederlund et al.

1979). Although loop antennas are bi-directional (the signal can be received equally strong from

two different directions simultaneously), by merely moving a few hundred meters perpendicular

to the bearings, and taking a second bearing, once can determine the direction of signal origin.

A more complicated antenna, the multi-element Yagi, is the most commonly used antenna in

North America (Kuechle 1982). It consists of a horizontal length of metal (usually aluminum)

with 3-17 vertical lengths attached to it, all in one plane. The length of the vertical elements and

their spacing depend on signal frequency. Yagi (Fig 8b) antennas are directional with shorter

elements at the distant end of the antenna. The signal‟s origin can be determined by swinging the

antenna and determining the direction of the strongest signal when the tip of the Yagi (the

shortest element) is farthest from the user (Mech 1983). Twin Yagi systems can be set up for

greater range and more precise directionality. However that requires careful spacing of the

antennas 1 or ¼ wavelength apart (Amlaner 1980; Anderka 1987).

Another type of receiving antenna is the Adcock, or „H‟ antenna (Fig 8c), often used for hand-

held applications because it is smaller than the Yagi. However, this antenna has reduced gain and

receives the signal equally strong from two directions, so the true direction of signal origin must

be confirmed in the same way as with a loop antenna (Samuel and Fuller 1996).

2.1.3. Immobilization equipments

Fig 9. Telinject air-rifle Fig 10. Vario 11 mm 3 ml lightweight syringe

dart and non-collared needle

Different power projection systems have been used for projecting the darts however for tigers;

the system that employs compressed gas/CO2 to propel the dart should be selected. Light weight

plastic darts of 3-5 ml. capacity should be used for remote injection using air powered/CO2 tele-

injection projector (Model 4V.310) from a distance of 15 meter (Fig 9). Needle length is critical

9

factor while darting tigers. The outside diameter of the needle should be 1.5- 2.0 mm and length

of 38- 40 mm (Fig 10).

2.1.4. Selection of Animal and approach to the target animal

The animal has to be located, which can be problematic for elusive or cryptic species and then

immobilized for long enough to attach the tracking device. Prior knowledge of the targeted

animal is required before fitting radio-collar. History on age-sex, area operated by the targeted

animal and group composition (with cubs/without cubs) is required. In case of problem tiger or

the tiger come in conflict, history of the animal is important. The information on group

composition is also important while selecting the animal for re-introduction. The selection of

lactating mother can be avoided as cubs can be disturbed during the operation. Young animal can

be collared when they are between 9 and 17 months (Smith 1993; Majumder et al. 2012). For

preparing suitable drug dosage to sedate the animal, age and predicted body weight is required

(Majumder et al. 2012).

A four wheel field vehicle or trained captive elephants may be used to approach the animal

taking due care of human safety and an overriding degree of patience. In a terrain where the

vehicle cannot be used, possibility of darting the animal from a machan (raised platforms) may

also be considered. Tigers in conflict provide limited opportunities for darting and therefore

require adequate experience by personnel in effective darting as well as knowledge of anatomical

peculiarities. Hindquarters should be preferred for teleinjection however depending on the

opportunities; other suitable areas can also be explored (NTCA Protocol on Immobilization and

Restraint of Tigers/http://projecttiger.nic.in/WriteReadData/CMS/Final_SOP_11_01_2013.pdf).

2.1.5. Drug use for sedation and its antidote

The animals can be radio-collared following

immobilization with “Hellabrunn mixture”

(125 mg xylazine + 100 mg ketamine/ml) (Halfner

et al. 1989) (left picture). Initial dose depends on

estimated body weight and sex of the animal and

ranged from 2.5 ml for sub-adult to 2.75 ml for adult

female and 3 ml for adult male. The induction time

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ranged between 26-36 minutes and effective handling time was 25-29 minutes. The drug

combination induced reliable immobilization with good muscle relaxation and no significant

alteration in physiological responses. Yohimbine hydrochloride administered intramuscularly at

a dose of 5 mg for every 50 mg of xylaxine (Seal et al. 1987; Majumder et al. 2012) can be

provided effective reversal for the tigers and which can be resulted in complete recovery that

ranges from 10-28 minutes. Another immobilization drug is Medetomidine hydrochloride

(ZALOPINE, Orion Corporation, Espoo, Finland). Atipamezole hydrochloride (ANTISEDAN,

Orion Corporation, Espoo, Finland) can be administered intramuscularly as antidote to negate the

medetomidine induced immobilization within 10 minutes (NTCA Protocol on Immobilization

and Restraint of Tigers).

2.1.6. Important steps to be followed once the tiger is darted

1) Carefully observe the sedated animal

from a safe distance (left picture), whether it

is completely sedated or not. A stick can be

bitten on the ground for making soft sound.

Animals panic when distressed and will flee

from the source of disturbance until they are

exhausted and can die of resultant heart

failure, termed capture myopathy (Ebedes et al. 2002). For this reason, the stress imposed

on wild animals during capture and handling should be kept to a minimum and loud noises

and movement should be avoided.

2)

3)

4)

5)

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2) If the animal under complete sleep, dart need to be removed. Blindfolding to protect the

cornea from direct sunlight, dust and injury (above pictures).

Fig 11a and 11b. Ideal animal position after sedation

3) Ensuring proper animal positioning (sternal or lateral recumbancy) to maintain patent

airways and ensure normal breathing and circulation (Fig 11a and 11b).

4) Assessing the status of animal, the degree of muscle relaxation and the rate and depth

of respiration.

5) Assessment of anesthesia should be done using following methods:

i) Monitor tissue perfusion: Anesthetic drugs frequently depress the contractile force

of the heart and vasodilatation results in decreased tissue perfusion.

ii) Evaluation of tissue perfusion should be done by observation, auscultation,

palpation and capillary refill time.

iii) Monitor gas exchange: Respiratory rates are highly variable during anesthesia.

iv) Quality of respiration should be evaluated by observing animal‟s chest movement.

v) Monitor level of CNS depression by assessing the muscle tone-jaw tone and eye

reflexes.

vi) Monitor vital signs such as respiration, heart rate and body temperature.

vii) Examine animal for any wound or injuries (including status of canines and claws).

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Fig 12. Various activities need to be carried out

6) The sedated animals need to be measured, weighed (Annexure 1), monitored the

physical condition of the animal (Pulse rate or heart bit, body temperature, properly

respiration is happening or not etc), radio-collared, and photographed. Individuals can

be aged using tooth wear, eruption, and body size, evidence of sexual development and

previous births, and overall body condition (Fig 12).

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7) Other broad physical parameters (cover, GPS location, nearest human habitation, water

sources etc) of that place need to be taken.

8) The blood and hair samples need to be taken for histo-pathological and genetic study.

Fig 13. Water need to be sprayed on the Fig 14. Giving reversal drug to the animal

sedated animal

9) Water need to be sprayed on the sedated/immobilized tiger at a regular interval to

maintain the body temperature (Fig 13). Once anti-sedan is given, the animal need to be

monitored until it completely gets up (Fig 14).

10) Ground team should be alerted before giving the antidote or anti-sedan. Animal health

should be under close observation even at least 2/3 days, whether any adverse effect of

drug is happened or not (eg. Stop feeding, slow movement, loose motion etc).

11) If the animal is an adult one, we need to follow whether it is able to hunt its prey or

not.

2.1.7. Tracking methods

Techniques that have been used for many years especially in VHF tracking, such as

triangulation and homing (Fig 15a and 15b). Other than both of these tracking methods,

automatic tracking devices have been also widely used to track radio-collar animal.

Homing - For “Homing”, the radio-collared tigers can be located and monitored from

elephant back and four wheel drive vehicle. Attempts can be made to locate at least one and

when possible two animals on daily basis. The located animals were „homed in‟ from

elephant back or on foot. Care need to be taken not to disturb tiger‟s natural behaviour or

movement. Once the animal can be sighted, a hand held Global Positioning System (GPS)

shall be used to record its coordinates. The actual sighting of each animal helped the

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accuracy of the GPS locations obtained for use in home-range analysis and also gave

additional data on activity, behaviour and interaction with other tiger especially with cubs

(Annexure 2).

Fig 15 a and 15 b. Tracking of radio-collared animals/tigers

Triangulation- Triangulating involves obtaining two signal bearings from different locations

(preferably at angles of about 90o to one another) which then cross at the animal. In practice,

it is better to take three or four bearings because antenna directionality is imprecise. When

more than two bearings are plotted, the bearings form an error polygon on a map (Heezen

and Tester 1967; White and Garrott 1990). This polygon theoretically contains the animal‟s

location. Significant error can be introduced if the bearings are not taken in a relatively short

period, since the more time that passes, the greater the probability that the animal has moved.

This problem can be avoided by researchers simultaneously taking bearings each from a

different location. Triangulation locates an animal with minimal disturbance since the

researcher can be far from the animal while obtaining a bearing.

Automatic Tracking- Automatic radio-tracking differs from the above techniques because

the researcher is not required to be in the field to obtain the animal‟s location. The obvious

advantage is reduced human presence in the field. Satellite telemetry is used as automatic

tracking system. Satellite telemetry utilizes a platform transmitter terminal (PTT) attached to

an animal which sends an ultra high frequency (401.650 MHz) signal to satellites. The

satellites calculate the animal‟s location based on the Doppler effect and relay this

information to receiving/interpreting sties on the ground. PTTs are attached by collars,

harnesses, subdermal anchoring, harpooning with a connected float, or by fur bonding

(Taillade 1992). Data from radio-collars with satellite link (ARGOS and IRRIDIUM) can be

downloaded as and when received with good quality (Mech and Barber 2002).

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2.1.8. Data Analysis

The formal concept of an animal‟s home range, or derivations thereof, has been around for

over half a century (Burt 1943). Within this time frame there have been countless published

studies reporting home range estimators with no consensus for any single technique

(Withey et al. 2001; Laver and Kelly 2008). Recent advances in GPS technology for

monitoring home range and movements of wildlife have resulted in locations that are

numerous, more precise than VHF systems, and often are auto correlated in space and time.

Along with these advances, researchers are challenged with understanding the proper

methods to assess size of home range or migratory movements of various species. The most

acceptable method of home-range analysis with uncorrelated locations, kernel-density

estimation (KDE), has been lauded by some for use with GPS technology (Kie et al. 2010)

while criticized by others for errors in proper bandwidth selection (Hemson et al. 2005) and

violation of independence assumptions (Swihart and Slade 1985b). The issue of

autocorrelation or independence in location data has been dissected repeatedly by users of

KDE for decades (Swihart and Slade 1985a; Fieberg 2007) and can be especially problematic

with data collected with GPS technology.

Recently, alternative methods were developed to address the issues with bandwidth selection

for KDE and auto correlated GPS data. Brownian bridge movement models (BBMM), which

incorporate time between successive locations into the utilization distribution estimation,

were recommended for use with serially correlated locations collected with GPS technology

(Bullard 1999; Horne et al. 2007). The wrapped Cauchy distribution KDE was also

introduced to incorporate a temporal dimension into the KDE (Keating and Cherry 2009).

Improvements were developed in bandwidth selection for KDE (e.g. solve-the-equation,

plug-in; Jones et al. 1996; Gitzen et al. 2006) and biased random walk bridges were

suggested as movement-based KDE through location interpolation (Benhamou and Cornelis

2010; Benhamou 2011). Other methods incorporated movement, habitat, and behavior

components into estimates of home range that included model supervised kernel smoothing

(Matthiopoulos 2003) or mechanistic home-range models (Moorcroft et al., 1999). Finally,

local convex hull nonparametric kernel method, which generalizes the minimum convex

polygon method, was investigated for identifying hard boundaries (i.e. rivers, canyons) of

home ranges but has not been evaluated with GPS data sets with >1,000 locations (Getz and

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Wilmers 2004; Getz et al. 2007). The multitude of advanced methods, lack of standardized

procedures for setting input parameters, and advancements in theory makes it an arduous task

for researchers to select the methods that best suit their needs.

As GPS technology advances so has the software available. Several researchers have

summarized software available to analyze KDE, most often as extensions for Geographic

Information System (GIS) software such as the Home Range Tools extension (Rodgers and

Kie 2010) for ArcMap 9.x (ArcMap; Environmental Systems Research Institute, Redlands,

CA; Lawson and Rodgers 1997; Kernohan et al. 2001). For details on software cost,

operation systems compatibility, distributors, and bandwidth selection available for KDE see

Larson (2001), however, some of these software have since been updated or lost technical

support within the past several decades. Also in the past decade, the increased popularity of

the freely available, open-source software Program R (R Foundation for Statistical

Computing, Vienna, Austria; hereafter referred to as R) resulted in the development of R

packages to estimate KDE home ranges. Estimates of BBMM home range can be calculated

in R packages (BBMM, Nielson et al. 2011; adehabitat, Calenge 2006) and the independent

Animal Space Use software (beta version 1.3; Horne et al. 2007). Here, we restricted our

analyses to use of adehabitat (Calenge 2006) and ks (Duong 2007) R packages for KDE and

package BBMM (Nielson et al. 2011) to calculate BBMM home range. We acknowledge that

some estimation methods (e.g. LoCoH) or software (e.g. BBMM function in adehabitat) are

absent from our analyses; however, our goal was not to provide a complete comparison of all

methods, but rather to use freely available methods and software to highlight the challenges

of estimating home range with large GPS datasets.

ACKNOWLEDGEMENTS

We are thankful to National Tiger Conservation Authority (NTCA), Wildlife Institute of

India, Wildlife Conservation Society and Tiger Range Countries for sharing their information

on radio-telemetry studies. A special thank to Dr. Parag Nigam, Dr Y.V. Jhala, Dr K Sankar,

Mr Qamar Qureshi, Dr K Ramesh, Dr Kaustubh Sharma, Dr. Kaushik Banerjee, Dr Bhaskar

Acharya and Officials and staff from Kanha and Pench Tiger Reserve, India for sharing

valuable information, photographs on tiger collaring and telemetry equipments.

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22

Annexure 1

Data Sheet for Recording and Monitoring Immobilized Animal

Area Details

Date …………………………...………….

Location ……………………………………. GPS Lat…………….……….

Long………………..

Collar Frequency ………………………………………………………………………………

Purpose of capture …………………………………………………………………………….

Ambient temperature ……………………………. Day (cloudy, bright) ………………………

Animal Details

Species ………………………………………….…. Physical condition ……….………………..

Emotional state before drugging …….................. Sex …………………………………………

Approximate age ………………….………….…… Weight (kg)…………..………………….…

Breeding status …………………………..............

Body Measurements

Nose tip to Tip of tail ……………………………. Nose tip to base of tail …………………...

Nose tip to base of skull (Occipital) …………… Tail length………………………………….

Height (Shoulder blade to heel) …………………….. Hind limb length ……………………….

Left fore limb or Hind limb paw dimension Length ………………… Width …………………….

Neck girth ……………….…………….. Length of Canines ………………………..

Immobilization Details

Name of Immobilizing Drug(s) Time of

Injection

Drug dose

given

Route Site

1.

2.

3.

4.

23

Behaviour at the time of darting

(running, walking, standing, excited)………………………………………………………………

Induction time when animal goes down/ approached………………………………………...

Animal Monitoring

Time Signs shown

following

immobilization

Respiration

Shallow/ deep/

irregular & rate

Temperature

(0F)

Pulse

(rate)

Drug reversal

Name of reversal Drug(s) Time of

Injection

Drug dose &

volume given

Drug dose &

volume given

Site

Time when animal shows first sign of recovery - …………………………………………………

Details about recovery event till animal regains consciousness /shows signs of recovery

………………………………………………….………………………………………………….

Any other comments - …………………………..………………………………………………

Supplemental drugs

Name of other supportive

Drug(s)/antibiotic(s) etc. given

Trade name Volume used Route Site

1

2

3

4

24

Biological sampling

Name of

sample

Preservative

used

Examination

required

Handed over to Remarks

(Source: NTCA Protocol on Immobilization and Restraint of

Tigers/http://projecttiger.nic.in/WriteReadData/CMS/Final_SOP_11_01_2013.pdf).

25

Annexure 2

Data sheet for Homing Exercise

1) Date Time

2) Tiger ID…………………………………..Collar frequency………………………….

3) Age:

4) Sex

5) Health condition (any injury present or not)

6) Date: Time:

7) Place:

8) GPS coordinates: Longitude

Latitude

9) Weather condition

10) Association (number of adult/cub etc)

11) Kill present/Absent

12) If present, Prey species…………………………Age…………………Sex……………….

13) Broad terrain type (Undulating, plain, rocky etc)

14) Broad vegetation type

15) Nearest water hole (in meter)

16) Nearest human habitation (in meter)

17) Any other co-predator present

18) Any prey species present in near vicinity

19) Activity of tiger (sleeping, feeding, walking, roaring, playing with cubs, hunting, scat

defecating, fighting)……….

20) Duration of the study/Time spent

21) Remarks (Any interesting observation which is not mentioned above)

………………………………………………………………………………………………

………………………………………………………………………………………………

………………………………………………………………………………………………

………………………………………………………………………………………………

…………………………………………………………………………..............................

Global Tiger Forum- An Inter-Governmental and International

Body to Conserve Tiger in the Wild