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De Angelo et al 2010 JWM Track identification.pdf


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Journal of Wildlife Management 74(5):1141–1153; 2010; DOI: 10.2193/2009-293

Tools and Technology Article

Traditional Versus Multivariate
Methods for Identifying Jaguar, Puma,
and Large Canid Tracks
CARLOS DE ANGELO,1 National Research Council of Argentina (CONICET) and Asociacio´n Civil Centro de Investigaciones del Bosque Atla´ntico
(CeIBA), Yapeyu´ 23, CP 3370, Puerto Iguazu´, Misiones, Argentina
AGUSTI´N PAVIOLO, National Research Council of Argentina (CONICET) and Asociacio´n Civil Centro de Investigaciones del Bosque Atla´ntico
(CeIBA), Yapeyu´ 23, CP 3370, Puerto Iguazu´, Misiones, Argentina
MARIO S. DI BITETTI, National Research Council of Argentina (CONICET) and Asociacio´n Civil Centro de Investigaciones del Bosque Atla´ntico
(CeIBA), Yapeyu´ 23, CP 3370, Puerto Iguazu´, Misiones, Argentina

ABSTRACT The jaguar (Panthera onca) and puma (Puma concolor) are the largest felids of the American Continent and live in sympatry
along most of their distribution. Their tracks are frequently used for research and management purposes, but tracks are difficult to distinguish
from each other and can be confused with those of big canids. We used tracks from pumas, jaguars, large dogs, and maned wolves (Chrysocyon
brachyurus) to evaluate traditional qualitative and quantitative identification methods and to elaborate multivariate methods to differentiate big
canids versus big felids and puma versus jaguar tracks (n 5 167 tracks from 18 zoos). We tested accuracy of qualitative classification through an
identification exercise with field-experienced volunteers. Qualitative methods were useful but there was high variability in accuracy of track
identification. Most of the traditional quantitative methods showed an elevated percentage of misclassified tracks ( 20%). We used stepwise
discriminant function analysis to develop 3 discriminant models: 1 for big canid versus big felid track identification and 2 alternative models for
jaguar versus puma track differentiation using 1) best discriminant variables, and 2) size-independent variables. These models had high
classification performance, with ,10% of error in the validation procedures. We used simpler discriminant models in the elaboration of
identification keys to facilitate track classification process. We developed an accurate method for track identification, capable of distinguishing
between big felids (puma and jaguar) and large canids (dog and maned wolf) tracks and between jaguar and puma tracks. Application of our
method will allow a more reliable use of tracks in puma and jaguar research and it will help managers using tracks as indicators of these felids’
presence for conservation or management purposes.
L

KEY WORDS canids, discriminant function analysis, identification keys, jaguar, Panthera onca, puma, Puma concolor, track
differentiation.

Sign surveys are useful noninvasive tools to assess and
monitor elusive or rare species (Wemmer et al. 1996,
Gompper et al. 2006). Spoor counts have been used as
indicators of presence, relative abundance, and density
estimation of different species (Van Dyke et al. 1986,
Stander 1998, Crooks 2002, Wilting et al. 2006). Likewise,
many studies involving endangered species have used sign
surveys to obtain basic ecological information (e.g.,
distribution and habitat use; Perovic and Herran 1998,
Potvin et al. 2005, Markovchick-Nicholls et al. 2008) and as
preliminary or complementary assessment in ecological
research or conservation plans (Schaller and Crawshaw
1980, Rabinowitz and Nottingha 1986, Soisalo and
Cavalcanti 2006, Paviolo et al. 2008). Tracks are not only
one of the most commonly used signs but they may also be
useful in identifying other associated signs such as fecal
samples (Wemmer et al. 1996, Scognamillo et al. 2003,
Shaw et al. 2007, Azevedo 2008). However, one of the
problems of employing tracks and other signs is correct
identification of the species, particularly in areas where 2
similar species are likely to be found and where little or no
information about their presence is available.
Because track shape is affected by many factors (like
substrate quality or the pace of the animal) it is often
difficult to distinguish tracks of similar species, particularly
in areas where soil conditions make track printing difficult
L

1

E-mail: biocda@gmail.com

De Angelo et al. N Large Felid and Canid Track Identification

and only few tracks are found in each event (Fjelline and
Mansfield 1988, Wemmer et al. 1996, Grigione et al. 1999,
Lewison et al. 2001). Multivariate analyses have been used
to reduce subjectivity and improve accuracy in sign
recognition (Zielinski and Truex 1995, Zalewski 1999,
Harrington et al. 2008, Steinmetz and Garshelis 2008). In
addition, multivariate analyses of feline tracks have been
used for more demanding objectives like sex determination
and individual identification (Smallwood and Fitzhugh
1993, Riordan 1998, Sharma et al. 2003, Wilting et al.
2006, Isasi-Catala´ and Barreto 2008; but see Karanth et al.
2003 and Gordon et al. 2007).
Jaguars (Panthera onca) live in sympatry with pumas (Puma
concolor) along most of their distribution and both species
are the focus of many research and conservation programs
(Nowell and Jackson 1996, Sanderson et al. 2002, Conroy et
al. 2006, Shaw et al. 2007). These felids also share most of
their range with some large canids, such as pumas with gray
wolves (Canis lupus) and coyotes (C. latrans) in North
America, both felids with the maned wolf (Chrysocyon
brachyurus) in central South America, and both felids with
the domestic dog in most of their distribution.
Tracks of pumas and jaguars have been employed for
research, monitoring, and management (Smallwood and
Fitzhugh 1995, Hoogesteijn 2007, Shaw et al. 2007).
However, it is often difficult to differentiate between puma
and jaguar tracks because they are similar in size and shape
and both are frequently confused with big canids’ tracks
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