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Unusual observation of an ocelot (Leopardus pardalis) eating an adult Linnaeus’s
two-toed sloth (Choloepus didactylus)
Miguel Delibes a,∗ , Javier Calzada b , Cuauhtémoc Chávez c , Eloy Revilla a , Beatriz A. Ribeiro d ,
Denise Prado e , Claudia Keller e , Francisco Palomares a
a
Department of Conservation Biology, Estación Biológica de Doñana, CSIC, Sevilla, Spain
Departamento de Biología Ambiental y Salud Pública, Universidad de Huelva, Huelva, Spain
Laboratorio de Ecologia y Conservación de Fauna Silvestre, Instituto de Ecología, UNAM, México, D.F., Mexico
d
Parque Nacional do Viruá, IBAMA/ICMBio, Boa Vista, RR, Brazil
e
Instituto Nacional de Pesquisas da Amazônia–INPA, Department of Ecology, Manaus, AM, Brazil
b
c
a b s t r a c t
Keywords:
Amazonia
Felids
Prey use
Viruá National Park
The behaviour of an ocelot (Leopardus pardalis) eating from an adult Linnaeus’ two-toed sloth (Choloepus
didactylus) was described. Observation was made at the Viruá National Park of northern Brazil. The sloth
had an estimated weight of 7 kg and a portion of its hairs were plucked after the kill. The ocelot began to
eat its prey by the braincase. Three days after the finding, only the harder parts of skin and the bones of
the extremities of the sloth remained. Field observations of ocelots while eating are very rare and sloths
are unusual prey.
The ocelot (Leopardus pardalis) is one of the best known neotropical cats, with a distribution ranging from southern Texas to
northern Argentina and occupying a large variety of covered habitats, from tropical humid forests to marshes and dry scrublands
(Murray and Gardner, 1997; Sunquist and Sunquist, 2002). Until
recently, it was commonly accepted that the ocelot was specialized
on small sized prey, mainly rodents (Emmons, 1987). For example,
more than 90% of the ocelot prey in Venezuela weighs less than 1 kg
(Sunquist and Sunquist, 2002) and more than 65% of its prey in Peru
weighs less than 100 g (Emmons, 1987). Larger prey, however, such
as capybaras (Hydrochaeris hydrochaeris), agoutis (Dasyprocta spp.),
brocket deer species (Mazama spp.), armadillos (Xenarthra), peccaries (Tayassu spp.) and monkeys (Primates), are occasionally taken
(Murray and Gardner, 1997; Sunquist and Sunquist, 2002). However, recent evidence suggests that local populations may strongly
depend on large prey items. For example, at Caratinga Biological
Station, southeast Brazil, ocelots feed mainly on small rodents and
birds, but primates, especially the brown howler monkey (Alouatta
guariba), were found in 27% of the analyzed faeces (Bianchi and
Mendes, 2007). The authors attribute the high frequency of howler
monkeys in ocelot diet to the high density of these primates (≥1
∗ Corresponding author at: Department of Conservation Biology, Estación Biológica de Doñ ana, CSIC, C Américo Vespucio, s/n, Isla de la Cartuja, 41092 Sevilla, Spain.
Tel.: +34 954 466700; fax: +34 954 621125.
E-mail address: [email protected] (M. Delibes).
individual per hectare) and their relative vulnerability in the study
area. In the same way, on Barro Colorado Island, Panama, Moreno et
al. (2006) showed that the ocelot relies mostly on Central American
agoutis (Dasyprocta punctata) and sloths (Choloepus hoffmanni and
Bradypus variegatus). The authors consider that the ocelot shifted
its diet towards larger prey on Barro Colorado as a result of the competitive release motivated by the absence of the jaguar (Panthera
onca) on the island.
Ocelots are rarely sighted in nature (Emmons, 1988) and we do
not know of any direct observation of ocelots closely associated to
a large prey (most data come from analyses of faeces). Thus, the
way they kill and manipulate prey in the wild is unknown. Here
we report on a direct observation of an ocelot after presumably
capturing and eating an adult Linnaeus’ two-toed sloth (Choloepus
didactylus) at the Viruá National Park (northern Brazil). The Viruá
National Park (01◦ 29t 12tt N, 61◦ 02t 52tt W, 01◦ 26t 29tt S, 61◦ 00t 08tt E)
covers 227,000 ha at the center of the state of Roraima (Brazil),
and it is bordered by the Branco river and its tributary Anauá.
The vegetation is characterized by a transition between grass- and
scrubland (campina), lower-canopy and more open forest (campinarana), and higher-canopy, more dense and humid forest. The
area is generally flat, with isolated rocky elevations 45–365 m
high, and a large portion is subject to seasonal flooding. Forests
are distributed along water bodies and on the higher terrain.
Mean annual rainfall is 1750 mm, and concentrates in the rainy
season, from April to August. A relatively extended dry season
occurs from September to March. Mean annual temperature is 32 ◦ C
(Machado et al., 2004). A 25-km2 trail system with a 1 km × 1 km
grid resolution was installed in the northeast of the park in 2006
(http://ppbio.inpa.gov.br), making easy to walk on the forest and
enabling direct observations of flora and fauna.
On the morning of March 05, 2009, one of us (MD) and an experienced field technician were walking slowly (approx. 1 km/h) along
one of the trails of the 25-km2 trail grid, as part of a visual-sampling
survey of medium-sized and large mammals. At 08:25 solar time,
in an area of campinarana forest we spotted an ocelot near the trail,
laying on the ground. As we approached, the ocelot calmly rose
and walked away into the forest. About 4 m away from the ocelot’s
bed we located a fresh carcass of a large Linnaeus’s two-toed sloth
which had an estimated weight of 7 kg. Scattered hair tufts around
the carcass suggested the hairs of the sloth were plucked, as ocelots
are reported to do with bird feathers and long-haired mammals
(Leyhausen, 1979). The sloth lacked the braincase (but not the
mandible), the eaten portion being about 200 g. The remaining body
length was 60 cm. We were unable to find any other wound on the
sloth’s body, so it was probably killed by a bite on the nape or the
head, as do most felids, including ocelots (Leyhausen, 1979). Felids
also usually begin to eat their prey by the head, except if they are
unable to break the braincase bones (Leyhausen, 1979). The close
proximity of the predator’s resting place to its partially eaten prey
could be interpreted as some kind of prey guarding.
We left the place after several minutes. Nine hours later (at
17:15 h), the sloth carcass had been moved 35 m far of the trail.
The neck, shoulders and part of the chest had been eaten (about
1 kg). The content of the stomach laid 3 m away from the body.
Another of us (JC) returned to the same spot on the morning of the
following day, observing from a distance that the carcass had been
moved again and finding new tracks of two different ocelots (specific assignation based on track measurements; Calzada et al., 2007)
in a print trap installed 200 m away from the carcass location. The
tracks were apparently coming from the direction of the carcass.
Observations of pairs of ocelots are not rare (see a short review
in Mondolfi, 1986), so two individuals could have been eating the
sloth. Three days after the finding, only the harder parts of skin and
the bones of the extremities remained, covered with plenty of flies
and larvae. No signs of other scavengers were detected.
Linnaeus’s two-toed sloths live in the canopy and are a common prey of harpy eagles (Harpia harpyja) (Galetti and de Carvalho,
2000; Múñ iz-López, 2008). However, they descend to the ground to
defecate and to move from one tree to the other, being then exposed
to many terrestrial and semi-arboreal predators (Adam, 1999).
Among 774 vertebrate prey items recorded in six studies of ocelot
diet (we excluded those in Cockscomb Basin of Belize, reviewed
by Sunquist and Sunquist, 2002, and the tropical deciduous forest
in Jalisco, Mexico, by Villa-Meza et al., 2002, as presumably sloths
do not live there), we have found only one sloth record (Bradypus variegatus, the brown-throated three-toed sloth; among 30
vertebrate prey items recorded in the Atlantic rainforest of Southeast Brazil; Wang, 2002). No sloth appeared among the prey of
ocelots in Iguazú National Park in Brazil (minimum number of vertebrate prey recorded, vp = 75) and Guárico in Venezuela (vp = 269),
reviewed by Sunquist and Sunquist (2002), Manu National Park in
Peru (vp = 177; Emmons, 1987), Araucaria pine forest of Paraná in
Southern Brazil (vp = 99; Abreu et al., 2008) and Caratinga Biological Reserve in Minas Gerais, Brazil (vp = 124; Bianchi and Mendes,
2007). The exception to this common pattern is the already quoted
situation on Barro Colorado island in Panama, where sloths can be
especially abundant and small prey especially scarce as a result
of competition and mesopredator release (Moreno et al., 2006).
However, pumas (Puma concolor) and jaguars are common in Viruá
(authors, unpublished data), hence a focus of ocelots on small prey
should be expected here. Our observation is exceptional because
continental ocelots only very rarely capture sloths (maybe this is
the first record of the species Choloepus didactylus as an ocelot’s
prey) and because none aspect of the behaviour of the species in
the wild while dealing with a large prey was previously described.
Acknowledgements
We thank João Batista Leite for assistance in field work, and
Antonio Lisboa, Iran das Chagas Almeida and Marlúcia Lima Costa
for logistical support at Viruá National Park. Miguel Clavero, Carlos
Gutiérrez and Julia Martínez helped in many ways. Sandro Lovari
improved the manuscript with his suggestions. The research was
carried out under a conservation biodiversity project supported by
the BBVA Foundation, authorized in Brazil by Expediç ão Científica
CNPq # EXC 003/08 (PO MCT # 206, DOU 08/04/2008) and SISBIO
license # 15664-1. The 25-km2 trail system in Viruá National Park
was installed by the Program for Biodiversity Research (PPBio) of
the Brazilian Ministry of Science and Technology (MCT).
References
Abreu, K.C., Moro-Rios, R.F., Silva-Pereira, J.E., Miranda, J.M.D., Jablonski, E.F., Passos, F.C., 2008. Feeding habits of ecelot (Leopardus pardalis) in Southern Brazil.
Mammalian Biology 73, 407–411.
Adam, P.J., 1999. Choloepus didactylus. Mammalian Species 621, 1–8.
Bianchi, R.D., Mendes, S.L., 2007. Ocelot (Leopardus pardalis) predation on primates in
Caratinga biological station, Southeast Brasil. American Journal of Primatology
69, 1173–1178.
Calzada, J., Keller, C., Palomares, F., Píriz, A., Delibes, M., Magnusson, W.E., 2007.
Identificación de felinos amazónicos en base a sus huellas. In: VIII Jornadas de
la SECEM. Sociedad Españ ola para la Conservación y Estudio de los Mamíferos,
Málaga, p. 31.
Emmons, L.H., 1987. Comparative feeding ecology of felids in a Neotropical rainforest. Behavioural Ecology and Sociobiology 20, 271–283.
Emmons, L.H., 1988. A field study of ocelots (Felis pardalis) in Peru. Revue Ecologie
(Terre Vie) 43, 133–157.
Galetti, M., de Carvalho Jr., O., 2000. Sloths in the diet of a harpy eagle nestling in
Eastern Amazon. The Wilson Bulletin 4, 535–536.
Leyhausen, P., 1979. Cat Behaviour. The Predatory and Social Behaviour of Domestic
and Wild Cats. Garland STPM Press, New York/London.
Machado, R.B., Aguiar, L.M., Ramos-Neto, M.B., Rodríguez, F.H.G., Hass, A., Aquino,
F.G., 2004. Atlas de Conservaç ão da Natureza Brasileira – Unidades Federais.
Metalivros. Mondolfi 1986, São Paulo.
Mondolfi, E., 1986. Notes on the biology and status of the small wild cats in
Venezuela. In: Miller, S.D., Everett, D.D. (Eds.), Cats of the World: Biology, Conservation and Management. Natural Wildlife Federation, Washington, DC, pp.
125–146.
Moreno, R.S., Days, R.W., Samudio Jr., R., 2006. Competitive release in diets of ocelots
(Leopardus pardalis) and pumas (Puma concolor) after jaguar (Panthera onca)
decline. Journal of Mammalogy 87, 808–816.
Múñiz-López, R., 2008. Revisión de la situación del Aguila Harpía Harpia harpyja en
Ecuador. Cotinga 29, 42–47.
Murray, L., Gardner, G.L., 1997. Leopardus pardalis. Mammalian Species 548, 1–10.
Sunquist, M.E., Sunquist, F., 2002. Wild Cats of the World. University of Chicago,
Chicago.
Villa-Meza, A., Meyer, E.M., Lópes-Gonzáles CA, 2002. Ocelot (Leopardus pardalis)
food habits in a tropical deciduous forest of Jalisco, México. American Midland
Naturalist 148, 146–154.
Wang, E., 2002. Diets of ocelots (Leopardus pardalis), margays (L. wiedii) and oncillas
(L. triginus) in the Atlantic rainforest in Southeast Brazil. Studies Neotropical
Fauna and Environment 37, 207–212.