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    Assessing jaguar abundance using remotely

    triggered cameras

    Scott Silver, Ph.D.Jaguar Survey Coordinator

    Jaguar Conservation Program

    Wildlife Conservation Society

    December 2004

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    Table of Contents

    I NTRODUCTI ON ____________________________________________________________ 3

    GETTI NG STARTED _________________________________________________________ 4

    CAMERA SELECTION _______________________________________________________ 6

    DESIGNI NG THE SURVEY ___________________________________________________ 8

    The assumptions of mark-recapture ___________________________________________ 8

    Fine-tuning the design ______________________________________________________ 10

    CAMERA DEPLOYMENT IN THE F I ELD ______________________________________ 13

    Before you deploy the cameras_______________________________________________ 13

    Choosing the camera trap site _______________________________________________ 14

    Setting the camera traps ____________________________________________________ 15

    Monitoring the cameras ____________________________________________________ 17

    PREPARI NG AND ANALYZI NG RESULTS _____________________________________ 17

    Program CAPTURE _______________________________________________________ 18

    Estimating density _________________________________________________________ 19

    REF ERENCES _____________________________________________________________ 23

    APPEND IX 1_______________________________________________________________ 24

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    This protocol should be viewed as a living document. Technological and analytical

    innovations will likely result in methodological changes and modifications to analytical

    techniques.

    GETTING STARTED

    Before beginning any research project, investigators should have a clear idea of what

    information they need to help them address their primary conservation issue or question. Before

    investing in a photographic recapture survey, researchers should be certain that abundance or

    density is a quantity that will really be of use to them. To carry out an abundance estimate based

    upon photograph/re-photograph ratios (hereafter referred to as camera trap estimates) the

    research team must have certain information and equipment.

    Minimally:

    1) maps or geographic knowledge of the study area;

    2) access to the study area and a means of traveling throughout the study area quickly enough tomonitor camera traps before they cease to function (because they have run out of either film

    or battery power);

    3) at least a rudimentary idea as to the topographic features of areas inhabited or sites visited bythe study animal, and their travel routes;

    4) enough people familiar with the function and maintenance of camera traps to deploy andmonitor the traps in a timely fashion; and

    5) a sufficient number of camera traps to photograph (i.e., capture) enough individuals of thetarget species to generate a statistical estimate of abundance.

    It helps to have:

    1) someone with a high degree of familiarity with the study area

    2) existing trails or roads to facilitate access to the study area

    3) extra camera traps to act as replacements in the event of equipment failure

    4) a thumb nail estimate of capture rates for the target species

    5) rough estimates of home range size and life history information

    6) hand held GPS units

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    Before you deploy cameras, do a pilot study!

    As with most research projects, the value of a pilot study for camera trapping cannot be

    overstated. The advantages include:

    Famil iari ty with equipment A pilot study can reduce the loss of valuable data through faulty

    set up and deployment of camera traps. Practicing with your equipment in the study area helps

    minimize mistakes such as setting up cameras facing the wrong direction relative to the animals

    route of travel, or pictures that fail to photograph clearly identifiable marks because the camera is

    too close, too far away, or at a poor angle.

    Reali sti c assessment of capture success rateThis allows the researcher to estimate how many

    cameras and how large an area is needed to sample in order to collect enough data for the mark-

    recapture analysis.

    Reali stic assessment of moni tor ing effor t The rate at which the film and the batteries need

    replacement depends upon a number of factors. By establishing how many animals (both target

    and non-target species) are photographed and how long batteries function under your particular

    field conditions, it can be estimated how often you need to visit the cameras for routine

    maintenance such as film and battery replacement. You will also be able to estimate the rate of

    equipment failure.

    Tr aini ng of fi eld assistants Even if the principal investigator is familiar with the use of the

    camera traps, a trial period allows other project personnel to develop a sufficient level of

    expertise in their use. It also familiarizes the research team with the required logistics of

    deployment and monitoring, and ensures that sickness or injury to the principal investigator does

    not result in the failure of the survey.

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    In summary, a pilot study will ensure that when you come to conducting a formal survey,

    you will maximize the number of captures of the target species. This increases the accuracy of

    the abundance estimate, while saving time, effort, and resources.

    CAMERA SELECTION

    Camera traps can be grouped into two broad categories, active or passive, based upon their

    triggering mechanism.

    Activetraps:

    Active traps take a picture when an animal or object crosses an infra-red beam. These

    cameras rarely miss target animals, but are prone to false captures for example, from wind-blown

    leaves and rain drops. Particularly windy or rainy days can expend entire rolls of film on non-

    target images.

    Passive traps:

    These are triggered when an object with a different temperature than the ambient

    temperature moves within the cameras detection zone. These cameras are less prone to false

    captures, but are more prone to heat blindness when high ambient temperatures approach

    mammalian body temperatures. Direct sunlight compounds this problem.

    Traditionally, camera traps have employed cameras that use film. Digital camera traps

    have recently been added to the mix of choices. The ability to eliminate film and to store many

    more pictures make the prospects of digital cameras appealing, however two obstacles limit their

    usefulness in jaguar surveys: 1) digital cameras in ready-to-shoot mode drain current very

    quickly so batteries must be replaced frequently. Note: many makers advertise long (2-3 month)

    battery life but this usually is calculated with the camera in sleep mode which conserves

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    batteries but requires three seconds or more to awaken on detecting an animal; and 2) the shutter

    lag i.e., the time between when an animal is detected and when the image is captured, can be

    prolonged. If greater than 1 second, the target may have moved by the time the camera fires.

    As different camera trap models have different features and designs, the choice of a

    model is often dictated by the particular characteristics of the individual study. Here is a partial

    list of considerations for choosing camera traps:

    CostCurrently, camera traps range from about $50-$ 500. With anywhere from 20-50 traps

    required for a jaguar abundance survey, financial requirements can vary tremendously.

    Technical experti se Some camera trap models require more expertise for proper use.

    Generally, those with active sensors require more technical expertise to deploy. Consider the

    level of expertise and experience required for whoever will be deploying and monitoring the

    cameras in the field.

    Monitori ng abil i ty When accessibility to camera traps is limited, visits to monitor cameras,

    may be infrequent, and battery life, film use and camera trap weight need to be considered.

    Carrying at least one replacement unit for all trips to monitor cameras is recommended. For long

    trips to many stations, you may need to carry more than one replacement. If it is necessary to

    carry the units long distances, larger and heavier units may be less desirable.

    Site secur i tyAlthough it is virtually impossible to stop a determined camera trap thief, some

    models possess anti-theft features that enable them to be locked. The most secure designs

    typically comprise a full metal case with a tamper-proof means of anchoring it to a tree. Youre

    your site is secure from theft and mischief, there are models with no anti-theft features, which

    reduces weight.

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    Weather Some camera trap brand models are in self contained, weatherproof units. Even

    amongst water-resistant models, some can be completely submerged, while others have sensors

    that are vulnerable to immersion and flooding.

    Access to techni cal support Ask other users about their experiences with manufacturer

    support. What is their warranty policy, how much do repairs cost, are they accessible by phone,

    and what is their turn-around time for replacements and repairs? All of these considerations can

    make a significant difference to the number of camera traps that remain functioning under field

    conditions.

    DESIGNING THE SURVEY

    The assumptions of mark-recapture

    There are two critical assumptions that need to be satisfied when designing a camera trap

    survey. These assumptions are discussed in detail in Karanth and Nichols (1998) and

    summarized below.

    Population closure:

    The mark-recapture model is based upon a closed population i.e., no births, deaths,

    immigration or emigration of individuals within the study area during the survey. In reality few

    jaguar populations are actually closed, so in practice the assumption is satisfied by limiting the

    duration of the survey. The longer the survey, the greater the likelihood of violating this

    assumption. Based upon the life history characteristics of tigers, Karanth and Nichols felt that

    three months was a reasonable time-frame to assume a closed population. Similarly surveys on

    African leopards have typically used two to three months (Henschel & Ray 2003). Although

    there are few life history data available for jaguars, it is reasonable to assume the same duration

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    is satisfactory. Numerous jaguar surveys have used three months or less (Wallace et al. 2003;

    Silver et al. 2004; Maffei et al. 2004) as a data collection period.

    All animals have nonzero capture probability:

    The second important assumption is that every animal inhabiting the study area has at

    least some probability of being photographed (i.e., there is at least one camera trap within its

    range during the duration of the survey). It is important to realize that not every jaguar in the

    study area needs to be photographed, but that every animal has some chanceof being

    photographed. This assumption dictates how far apart your camera traps can be placed and

    determines the maximum size of a contiguous area within the study site without at least one

    camera trap. The camera stations can be as closeas the researcher is inclined to set them, but

    there should not be gaps between camera stations large enough to encompass a jaguars home

    range. A conservative approach to satisfying this assumption is to adopt the smallest home range

    estimate documented for your target species in your habitat and/or geographic region, as the

    minimum area within which there must be at least one camera station. Once that minimum area

    is known, calculate the diameter of a circle with that area. This diameter is the maximum

    allowable straight-line distance between camera stations. An example of a camera deployment

    design is shown in Figure 1. In this case, a literature search established that 10 km2was the

    smallest home range size of jaguars in the study area. Therefore, 10 km2 is the maximum gap

    area allowed between camera stations and 3.6 km (the diameter of a circle with an area of 10

    km2) is the maximum straight line distance between cameras. Note that 10 km2is the maximum

    gap size; cameras can be placed closer than this. However, while there is no set minimum

    distance between stations, a survey will not be meaningful if all cameras are concentrated in a

    very small area that will only capture a few jaguars. A design that is too small carries the risk of

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    not sampling enough of the population to generate a reliable density estimate. The design must

    cover a large enough area to photograph numerous different individuals.

    Before selecting locations for the camera stations, decide for how long the cameras can

    be deployed, and how densely the camera stations can be spaced. In both cases, estimates can be

    conservative without violating any of the closed population model assumptions. There is no

    minimum time or camera trap density necessary for a mark and recapture study as long as

    sufficient data are collected to generate an estimate.

    Fine-tuning the design

    Once you have established your basic design that satisfies the assumptions, you need to

    fine-tune the placement of the camera traps. Remember, camera placement is notnecessarily

    random. Camera station locations should be selected to maximize the capture probabilities

    of jaguars in the study area, while covering as large an area as possible to maximize the

    number of individuals photographed. This is a balance between positioning cameras closely

    enough to satisfy the assumption of all animals having a nonzero capture probability (as

    described above), and covering a large enough area to photograph more individual jaguars. It is

    also desirable for the animals in the study area to have similar capture probabilities, to the extent

    possible. While there are ways to account for variable probability of capture, estimations are

    simpler and more precise when capture probabilities are similar amongst animals. Because of

    this, try to maintain a comparable density of camera traps throughout the sample area. The idea

    of placing many cameras within one animals home range, while placing only a single camera

    within the range of another, should be avoided.

    To plan your sampling design, begin with a topographic map of the study area. Mark

    sites with a high likelihood of photographing jaguars such as trails, dirt roads, etc. Space them as

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    far apart as possible without missing good jaguar sites, or without violating the assumption of

    geographic closure. Remember the cameras will have to be monitored, so keep in mind the

    logistical limitations of your design.

    After the ideal camera trap locations have been selected on the map, look for gaps

    between camera trap locations greater than the permitted gap size, and either add camera stations

    to fill in those gaps, or shift some of the existing sites closer together. Some camera stations may

    have to be located in areas with little or no jaguar sign, but avoid sites where you know a jaguar

    will not go (e.g., very steep slopes). New trails may need to be cut to establish some camera

    stations.

    Record the exact coordinates of these predetermined camera trap locations. For the

    purposes of this document, these locations are called your predetermined coordinates. These

    act as your general guide to camera placement but the ultimate position may differ slightly when

    you go to the field (explained in the next section).

    If the number of cameras is limited, the size of the trapping area can be increased as

    follows. Design two trapping patterns (i.e., grids) adjacent to each other and deploy them in

    two consecutive data collection periods. Using the full complement of cameras, collect data in

    the first grid for a sub-sample of the entire survey duration (e.g., 4 weeks), then move the

    cameras to the second grid, for the same amount of time (in this case, 4 weeks for a total survey

    duration of 8 weeks). When analyzing the data, treat the resulting data set as if both grids were

    run simultaneously, even though they were not. All jaguars photographed on the first day of

    eithergrid are treated as photographed on Day 1; those photographed on Day 2 of either grid are

    treated as photographed on Day 2, etc. Animals photographed on different days are considered

    recaptures. This technique can be repeated again if necessary (i.e., additional grids

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    incorporated), and the data analyzed the same way but take care to limit the totalsurvey duration

    within the time required to satisfy the population closure assumption.

    CAMERA DEPLOYMENT IN THE FIELD

    Before you deploy the cameras

    Film:

    It is critically important that every roll of film is labeled with the date of deployment and camera

    number (corresponding to the cameras location) before the cameras are placed in the field.

    When the film is collected and developed, you may have dozens of rolls from 20-30 different

    locations. It is vital that you know the location of all your photographs in order to estimate your

    effective sampling area (see below) .

    Date & time settings:

    Photographs are useless without an accurate date and time stamp. The date on the photograph is

    essential for determining the individual capture event. Each 24-hour period is considered a

    different event so that all pictures of an individual photographed on the same date are considered

    a single capture. While camera models may differ slightly in setting the time/date stamp the

    important consideration is that it is consistent among all cameras in the survey.

    Time delays:

    All camera traps can be programmed with a delay between successive pictures. This is important

    as groups of tourists, herds of peccaries, or other non-target animals can result in many wasted

    pictures, and more importantly, expend film before the survey is finished. A camera that is out

    of film creates a data gap in the survey design that may result in the loss of all data for that time.

    The delay setting should be based upon the likelihood of encountering large groups of non-target

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    animals: experimentation during the pilot study period will assist in selecting the length of the

    delay setting for your study site. Because a longer delay increases the probability of missing a

    capture, the rule of thumb should be to use the minimum length of delay you feel comfortable

    with.

    Each camera trap site (known as a camera station) should contain two cameras on either

    side of the trail, stream, or road, aimed at a perpendicular angle to the jaguars presumed

    direction of travel. It is recommended that you always incorporate two cameras per station to

    ensure pictures are taken of both sides of jaguars (to ensure identification from a single capture

    event) and supply a level of redundancy in case of camera failure.

    Choosing the camera trap site

    In the field, the researcher needs to find the best possible location as close as possible to

    the predetermined coordinates. The exact site is chosen to give the highest probability of

    obtaining useful photographs whenever a jaguar passes by. The goal is to photograph both

    flanks of the jaguar, since this is the area where the individual markings are easiest to

    distinguish.

    Pick a jaguar-friendly site Once in the vicinity of the predetermined coordinates, search for

    the nearest location with a good chance of visitation by a jaguar. Features such as trails, dirt

    roads, river banks, beaches, and game paths to water are all used regularly by jaguars. Look for

    jaguar sign (tracks, scrapes, or past sightings) nearby. Generally, if there is any sign even a few

    kilometers away on the same trail, the entire path is probably used by jaguars.

    Try to determine the travel path of the jaguarPick a site where the jaguars travel path is

    limited to the area that can be photographed by the cameras. For example, a place where there is

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    direct sunlight on the cameras as excessive heat can reduce the sensitivity of the sensors to

    endothermic animals. Cameras should be set back at least two meters from the nearest point

    where a jaguar might travel across the sensor. This allows for clear, focused pictures, and a large

    enough field of detection from the sensor. The longer the jaguar is in the detection zone, the less

    chance of missing a photograph. Because the sensor beam should be approximately shoulder

    high on a jaguar, the camera should be set approximately 50-70 centimeters off the ground and

    parallel to it. Both cameras should be faced slightly down the trail to prevent mutual

    interference, but aimed at approximately the same point.

    Use pliable, light gauge wire to secure the cameras to the selected tree trunk. Use pliers

    to tighten the wire when the position of the camera on the tree is satisfactory. If locks and chains

    (or bicycle lock) are necessary to secure the cameras against theft, wait until cameras have been

    tightened with the wire before securing them. Do not use the lock and chain to affix the camera

    to the tree, as it will not be pliable enough.

    Use fresh cut sticks and branches to help prop up and secure the camera to the tree trunk

    or other anchor. A well-placed twig placed between the camera housing and the tree trunk can

    help adjust the angle in which the sensor is pointed. (Always use live wood to brace cameras

    and adjust camera angles, since dead wood is too brittle).

    Once the camera is set, clear the area between the camera and the path of travel of all

    vegetation. Anything that obstructs the beam reduces the detection ability of the camera, and

    could result in obscured pictures. Large leaves can result in false triggers when the sun heats up

    a frond blowing in the wind. Also try to avoid pointing the cameras at objects in direct sunlight

    that may absorb heat and trigger sensors such as large rocks or sunlit streams.

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    Test the aim of both cameras by crossing in front of them. Do this on both the edges and

    the middle of the path. Most camera trap brands come equipped with an indicator light that will

    light up when the cameras sensor detects you. Approximate a jaguar by walking in a crouch,

    and a jaguar walking in a more relaxed fashion. Make sure that every conceivable angle at

    which a jaguar can pass in front of the camera is tested, and that in each instance a photograph is

    triggered.

    Occasionally, limitations in terrain or suitable trees hamper complete coverage of a trail.

    In that case, lay brush or other obstructions down one side of the trail to influence where the

    jaguar will walk. This technique is also useful if you are unable to set the camera well back from

    the trail, and wish to deter a jaguar from passing so closely to a camera that it cannot take a well-

    focused picture.

    Monitoring the cameras

    The amount of traffic (both target and non-target species) and sensitivity of the trap brand

    will dictate how often the film needs changing. It is very important that cameras do not run out

    of film during the study. The same is true of battery life. A proper pilot study will determine the

    safe interval between battery and film changes. All stations must be functioning throughout the

    study to meet all the assumptions of the study design. The ability to monitor the cameras

    sufficiently may be the limiting factor in how many stations are deployed. Remember to be

    conservative when estimating how often film and batteries need to be changed.

    PREPARING AND ANALYZING RESULTS

    As the film is collected from each camera, ensure that it is properly labeled with the

    associated camera number and the date it was deployed. When developing film, ensure that the

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    history of each individual during the survey. Each day (or group of days) of the sample period is

    considered a sampling occasion and is represented as a separate column in the matrix. For each

    jaguar 0 represents an occasion when the animal was not captured, or a 1 if the animal was

    photographed on that occasion. The number of rows is the same as the number of individuals

    photographed, and the number of columns reflects the number of sampling occasions. After the

    matrix is prepared, save it as text only. With the correct format statement it can be pasted

    directly into the CAPTURE software for analysis at the following web address:

    http://www.mbr-pwrc.usgs.gov/software/capture.html . Data can be analyzed directly on the

    website or CAPTURE can be downloaded to a computer. Both the website and Appendix 1 give

    examples of the format statement and the appropriate matrix for analysis by CAPTURE, as well

    as the particular tasks the program can complete.

    Estimating density

    The program CAPTURE generates an estimate of abundance, not of density. A density

    estimate is calculated by dividing the abundance estimates generated from CAPTURE by the

    effective sample area. The effective sample area encompasses the camera traps with a buffer

    around the outside that takes into account those individuals whose home ranges may include

    areas that are only partially contained within the sampling pattern. There are numerous methods

    to estimate this buffer (see Karanth and Nichols 2002). Karanth and Nichols used a buffer

    whose width was based upon half the mean maximum distance moved (HMMDM) among

    multiple captures of individuals during the survey period). In Belize, we determine the

    HMMDM and use a GIS to create a circular buffer around each camera station; the radius of this

    circle is the HMMDM. The merged area of all of the circular buffers represents the entire

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    sample area (Figure 2). Other studies have drawn a minimum convex polygon around the traps

    and buffered that polygon with a belt whose width measures HMMDM around the outside to

    estimate effective trap area (Karanth and Nichols 1998). Large lacunae (such as bodies of water,

    villages etc.) that could not possibly contain jaguars can also be subtracted from the effective

    sample area estimate.

    Using merged circular buffers around each camera to measure sample area provides a

    useful check on your initial trap design. The mean maximum distance moved (MMDM) is

    considered to be a measure of the diameter of the home range area. The MMDM can also be

    used to check your assumed minimum home range size and camera trap placement. If, when the

    camera traps are buffered, gaps are found in the camera trap design, this would indicate that the

    cameras had spaces in between them that are larger than a single home range, and that the

    assumption that every jaguar has a >0 probability of capture was not met (Nichols pers. comm.).

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    Figure 2. Effective sample area (in red) for Cockscomb Jaguar Survey represented by combined buffer areasaround each camera.

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    The mean maximum distance moved (MMDM) can vary widely between surveys (even

    in the same location), so where data are available from multiple surveys in the same place, we

    have opted to use one half of a cumulative MMDM when possible. This cumulative MMDM

    averages the maximum distances moved by all individuals from multiple surveys in different

    years in the same location. This increases the sample size and reduces the variance associated

    with the MMDM, and gives a more accurate estimate of the effective sample area.

    In addition to an estimated abundance number, the CAPTURE program will also generate

    a capture probability, a standard error of the abundance estimate and a 95% confidence interval.

    This method is not designed to give an absolute number, but to give a statistically robust estimate

    of the abundance range. The standard error and confidence interval provide measures of

    uncertainty associated with the abundance estimate and are thus important in determining how

    the estimate is interpreted.

    Similarly, the resulting density estimate cannot necessarily be used to extrapolate

    densities beyond the study area. Unless a region is particularly homogenous in habitat,

    abundance surveys generate useful estimates only for the survey area. It is unrealistic to assume

    that estimates generated from a survey can be broadly applied to larger areas that may have quite

    different topographic and meteorological gradients than are represented within the survey area.

    Acknowledgements

    I am grateful for the assistance provided by Linde Ostro and Luke Hunter in producing this protocol. Bothprovided numerous suggestions and rewrites at various stages that ultimately improved the manuscript.James Nichols, Kathy Conforti and Alan Rabinowitz also read over the manuscript and provided helpfulcomments and suggestions. Finally I would like to thank Rob Wallace, Andy Noss, Marcella Kelly, BartHarmsen and many others for the hours of thought provoking conversations that helped to improve myunderstanding of the camera survey methodology.

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    REFERENCES

    Henschel, P. & Ray, J. 2003. Leopards in African Rainforests: Survey and Monitoring

    Techniques. WCS Global Carnivore Program website.

    Karanth, K.U. & Nichols, J.D. (1998) Estimation of tiger densities in India using photographic captures and

    recaptures. Ecology79(8), 28522862.

    Karanth, K.U. & Nichols, J.D. (2000) Ecological status and conservation of tigers in India. Final Technical

    Report to the Division of International Conservation, U.S. Fish and Wildlife Service, Washington D.C.

    and Wildlife Conservation Society, New York. Centre for Wildlife Studies, Bangalore, India.

    Karanth, K.U. and Nichols, J.D. (2002) Monitoring tigers and their prey: A manual for researchers,

    managers and conservationists in Tropical Asia. Centre for Wildlife Studies BANGALORE India.

    Karanth, K.U. (1995) Estimating tiger (Panthera tigris) populations from camera-trap data using capture-

    recapture models. Bi ological Conservation71, 333338.

    Maffei, L, Cuellar, E, Noss, A (2004) One thousand jaguars (Panthera onca) in Bolivia's Chaco? Cameratrapping in the Kaa-Iya National Park. Journal of Zoology262 (3): 295-304

    Otis, D.L., Burnham, K.P., White, G.C., & Anderson, D.R. (1978) Statistical inference from capture data onclosed populations. Wildlif e M onographs62, 1135.

    Rexstad, E. & Burnham, K.P. (1991)User s guide for in teractive program CAPTURE. Abundance estimation

    of cl osed populati ons. Colorado State University, Fort Collins, Colorado, USA.

    Silver, S.C., Ostro, L.E., Marsh, L.K., Maffei, L., Noss, A.J., Kelly, M.J., Wallace, R.B., Gomez, H., Ayala, G.2004. The use of camera traps for estimating jaguar (Panthera onca) abundance and density using

    capture/recapture analysis. Oryx38 (2): 148-154

    Wallace, R.B., Gomez, H., Ayala, G., and Espinoza, F. (2003). Camera trapping capture frequencies for

    jaguar (Panthera onca) in the Tuichi Valley, Bolivia. Mastozoologia Neotropi cal10(1): 133-139

    White, G.C., Anderson, D.R., Burnham, K.P., & Otis, D.L. (1982) Capture-recapture and removal methods

    for sampling closed populations. Los Alamos National Laboratory, Los Alamos, New Mexico, USA.

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    APPENDIX 1

    Example of data sheet ready for analysis by CAPTURE. These data represent the capture

    histories for 8 jaguars (labeled A through H), on 35 individual trapping days. In this example,

    jaguar A was photographed on two separate occasions (day 4 and day 11). Four animals (B, D,

    F, and H) were only photographed once. The file should look like a capture input file as follows:

    title='Example Jaguar Survey'

    task read captures occasions=35 x matrixformat='(2x,a1,5x,35f1.0)'

    read input dataA 00010000001000000000000000000000000

    B 00000000000000000000000000000001000C 10000000000000000100000001000000000D 01000000000000000000000000000000000E 00000000000000100000000000100000000

    F 00000000010000000000000000000000000G 00000001000000000000100000000000100

    H 00000000000000000000010000000000000task closure testtask model selection

    task population estimate ALLtask population estimate APPROPRIATE

    In more detail here are the component lines:

    title='Example Jaguar Survey' This is the title you give to the

    survey

    task read captures occasions=35 x matrix x matrix refers to the

    format of the data

    format='(2x, a1, 5x, 35 f1.0)' 1.0 refers to data format

    read input data

    # of characters in the

    I.D.

    # spaces before

    animal ID# spaces between

    ID and data

    # trapping days

    # trapping days

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    25/25

    YOUR DATA

    task closure test

    task model selectiontask population estimate ALL

    task population estimate APPROPRIATE

    These are the tasks you are asking CAPTURE to perform.

    For more detail go to this website:

    http://www.mbr-pwrc.usgs.gov/software/capture.html