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FINAL REPORT
ECOLOGY AND CONSERVATION OF SYMPATRIC PAMPAS CAT AND GEOFFROY´S CAT
IN AN ENDEMIC ECOREGION OF CENTRAL ARGENTINA
Submitted to:
THE RUFFORD FOUNDATION
Prepared by:
JAVIER A. PEREIRA
“Gatos del Monte” Project – Association for the Conservation and Study of Nature (ACEN)
Iberá 1575 8vo. “B”, Ciudad de Buenos Aires (1429), Argentina
November 2005
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“GATOS DEL MONTE” PROJECT TEAM
Lic. Javier Pereira
Asociación para la Conservación y el Estudio de la Naturaleza (ACEN)
Lic. Natalia Fracassi
Asociación para la Conservación y el Estudio de la Naturaleza (ACEN)
Instituto Nacional de Tecnología Agropecuaria (INTA)
Med. Vet. Marcela Uhart
Field Veterinary Program - Wildlife Conservation Society (WCS)
Universidad Nacional del Centro (UNICEN)
Med. Vet. Hebe Ferreyra
Field Veterinary Program - Wildlife Conservation Society (WCS)
Med. Vet. Carolina Marull
Field Veterinary Program - Wildlife Conservation Society (WCS)
DVM MPVM Pablo Beldomenico
Facultad de Ciencias Veterinarias - Universidad Nacional del Litoral
Wildlife Disease Group Leahurst Veterinary Field Station, University of Liverpool
Web Page: www.acen.org.ar/gatosdelmonte_e.html
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TABLE OF CONTENTS
CAPTURE AND IMMOBILIZATION OF WILD CATS AT LIHUÉ CALEL NATIONAL PARK, CENTRAL
ARGENTINA
Javier A. Pereira, Marcela M. Uhart, Hebe del V. Ferreyra, Carolina Marull and Natalia G. Fracassi
Page 4
NUMERICAL AND SPATIAL RESPONSES OF GEOFFROY’S CAT (ONCIFELIS GEOFFROYI) TO A SEVERE
DECLINE IN PREY ABUNDANCE IN THE MONTE DESERT, ARGENTINA
Javier A. Pereira, Natalia G. Fracassi, and Marcela M. Uhart
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HELMINTHS OF GEOFFROY’S CAT, ONCIFELIS GEOFFROYI (CARNIVORA, FELIDAE) FROM THE MONTE
DESERT, CENTRAL ARGENTINA
Pablo M. Beldomenico, John M. Kinsella, Marcela M. Uhart, Gabriela L. Gutierrez, Javier A. Pereira,
Hebe del V. Ferreyra, and Carolina A. Marull
Page 36
HEALTH STATUS OF GEOFFROY’S CAT AT LIHUE CALEL NATIONAL PARK, CENTRAL ARGENTINA
Marcela M. Uhart, Javier A. Pereira, Hebe del V. Ferreyra, and Carolina Marull
Page 45
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CAPTURE AND IMMOBILIZATION OF WILD CATS AT LIHUÉ CALEL NATIONAL PARK,
CENTRAL ARGENTINA
Javier A. Pereira (1,3), Marcela M. Uhart (2,3), Hebe del V. Ferreyra (2,3), Carolina Marull (2,3), and
Natalia G. Fracassi (1,3)
(1) Asociación para la Conservación y el Estudio de la Naturaleza – Iberá 1575 8vo. "B", Buenos Aires (1429), Argentina.
(2) Field Veterinary Program, Wildlife Conservation Society – Estivariz 197, Puerto Madryn (9120), Chubut, Argentina
(3) “Gatos del Monte” Project – www.acen.org.ar/gatosdelmonte.html
INTRODUCTION
Pampas cat and Geoffroy´s cat are two small wild cat species which co-exist in large areas of
Argentina and Southern South America. Major ecology and biology information gaps exist for these small
felines. For Pampas cat, no current information is available on its spatial ecology or habitat use because
there have been no previous studies on this topic. At the same time, the interactions between this species
and the Geoffroy’s cat have never been evaluated. These wild cats appear to have similar conservation
threats, such as habitat loss and poaching, mainly for control of predation of domestic poultry and
livestock. In addition, Pampas cat and Geoffroy´s cat were heavily hunted for the international fur trade
until the middle of the 1980s and the high volume of this operation (at least 350,000 skins of Geoffroy´s
cats and 78,000 of Pampas cats between 1976-1978) could have severely reduced their population
numbers. At present, these species are protected in Argentina but due the scarce information available on
their natural histories it is impossible to asses the impact of habitat modification on their populations or to
develop scientifically sound conservation strategies to ensure their persistence in time. While the IUCN
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listed these cats as low risk species at a global scale (Category 5 for Pampas cat and 4 for Geoffroy´s cat),
the Argentine Society for the Study of Mammals (SAREM) categorized Pampas cat and Geoffroy´s cat as
"vulnerable" and "potentially vulnerable" species, respectively. The SAREM criteria probably better
represents the current situation of these species in Argentina, because it includes local factors and regional
threats in the analysis.
During March-April 2002 and May 2003, two capture stages for the project “Ecology and conservation
of sympatric Pampas cat and Geoffroy´s cat in an endemic ecoregion of Central Argentina” were
conducted in order to capturing and collaring a sample of individuals of the above-mentioned species. The
overall project focuses on the ecology of these sympatric felids in a protected area of central Argentina.
The objectives of this project’s stage were (1) to capture and radiocollar Geoffroy´s cats and Pampas cats,
and (2) to collect biological samples to analyze their basic physiological parameters (hematology, blood
biochemistry, etc.) and to perform parasitological, genetic, and disease studies.
STUDY AREA
Lihué Calel National Park (37°57´S and 65°33´W, 9901 hectares) is located in La Pampa
province, Central Argentina. This park represents the Monte ecoregion, endemic of this country,
deficiently protected (less than 2% of its 158,000 square miles) and listed as Vulnerable by WWF because
of seriously damaging effects due to human activities. The protected area consists of flat desert scrub (300
m.a.s.l.) and an isolated set of bare rock hills (590 m.a.s.l.) and is surrounded by an immense plain of
desert scrub divided into large cattle ranches. Vegetation is a mosaic of creosote bush or Jarilla (genus
Larrea), mixed shrub patches and open areas of grasses and forbs. Twenty-eight mammal species,
including four felids (Pampas cat, Geoffroy´s cat, Jaguarundi and Puma) inhabit Lihué Calel. These
species suffer a high hunting pressure outside the protected area, which represents one of their main
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regional conservation threats. Feral cats and dogs exist near the national park boundaries and they
constitute a potential health risk for the native carnivores.
MATERIALS AND METHODS
Small (82 x 27 x 32 cm) and large (107 x 32 x 32 cm) Tomahawk Live Traps and small (84 x 28 x 28
cm) and large (92 x 34 x 34 cm) ad hoc live traps were used to capture wild cats. All traps consisted of
single door openings, which were tripped by a foot treadle. Traps were baited in their rear portions with
live domestic pigeons or with a mixture of cow liver and fat with fish oil. Each trap was camouflaged
using local elements as forbs, branches and thorns, mainly in the rear portion to protect the bait. Traps
were generally set in groups of 2-4 along the roads, where recurrent visual sightings were done or where a
lot of spoors or feces were found. Traps were visited 2 or 3 times a day to check for captures and to feed
bait pigeons. After a successful capture, trap groups were moved to another place to avoid recapturing the
same individual.
Each captured animal was anesthetized by the intramuscular injection of Ketamine-Medetomidine and
the dosages varied according to each specimens´ weight and general status. While under anesthesia, cats
weight, sex, age (based on body condition and tooth wear) and standard body measurements (total length,
tail length, left ear length, left hind foot length, neck circumference and left upper canine length) were
recorded and a complete physical exam was practiced. Blood samples were collected for hematological,
genetic and disease studies. Additionally, we searched for ecto-parasites and collected fecal samples for
endo-parasitological studies. Vital parameters (body temperature and cardiac and respiratory rates) were
monitored during cat handling. All healthy individuals were equipped with a radiocollar weighing less
than 3 % of the cat’s body weight. Following handling, animals were placed in a recovery plastic kennel,
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monitored avery 30 minutes and released when alert and coordinated at the site of capture. Only subadult
(minimum mass 2.0 kg) and adult wild cats were collared.
RESULTS
During the study period, 16 different Geoffroy´s cats were captured, 5 in 2002 and 11 in 2003. Four (3
males and 1 female), and 10 (1 adult male, 8 adult females, and 1 subadult female) Geoffroy´s cats were
radiocollared in 2002 and 2003, respectively. One additional male (in 2002) and two additional females
(in 2003) were also captured, examined and released without collaring. Although in 2002 only one
individual was recaptured (an old, dehydrated male), five females were recaptured in 2003. Female OG04
was radiocollared and monitored during both 2002 and 2003. Identification, weight and morfometric
values of these Geoffroy´s cats are reported in Table 1.
Table 1. Identification, weight (kg) and measurements (mm) of Geoffroy´s cats captured at Lihué Calel. TL = Total length, T = Tail length, HFL = Hind foot length, EL = Ear length, UCL = Upper canine length, NC = Neck circumference
ID # Sex Age 1 Weight TL T HFL EL UCL NC OG01 M A 4,600 950 330 124 40,5 11,6 190 OG02 M A 4,300 909 316 109 31,0 8,4 195 OG03 M A 3,900 912 302 108 51,1 13,4 200 OG04 F A 2,800 852 259 98 41,0 12,3 165 OG05 M A 3,200 877 328 112 48,5 13,0 185 OG06 F A 2,700 860 330 110 46,0 9,0 210 OG07 F A 2,400 770 277 180 43,0 10,1 167 OG04 F A 2,300 832 275 98 40,0 10,0 158 OG08 F A 3,200 836 340 114 48,0 9,5 182 OG09 F A 3,000 839 280 99,8 39,0 11,9 181 OG10 M A 3,800 978 326 120 44,5 11,1 194 OG11 F SA 2,000 845 295 98,3 31,8 11,3 151 OG12 F A 3,000 860 320 109 43,3 12,0 175 OG13 F A 2,500 859 313 99,3 45,1 11,9 186 OG14 F A 3,000 832 316 106 42,0 11,5 196
1 SA = Subadult, A = Adult
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Studied individuals ranged in age from subadult to old adults. Except one female (OG11), which was a
poor body condition, the rest of the sampled individuals were apparently in good physical condition, and
no ectoparasites were found on them. All the captured cats remained relatively calm during the approach
and sedation processes, and anesthetics details are given in Table 2. All cats were safely handled and no
one was injured.
Table 2. Details of Geoffroy´s cats´ sedation on Lihué Calel.
ID # Drug Injected Dosage ITA MTB RTC
OG01 Ketamine Medetomidine
6,38 mg/Kg. 0,06 mg/Kg.
7 min. 41 min. 240 min.
OG02 Ketamine Medetomidine
5,81 mg/Kg. 0,11 mg/Kg.
7 min. 42 min. 120 min.
OG03 Ketamine Medetomidine
5,12 mg/Kg. 0,1 mg/Kg.
3 min. 43 min. 120 min.
OG04 Ketamine Medetomidine
5,35 mg/Kg. 0,125 mg/Kg.
5 min. 44 min. 150 min.
OG05 Ketamine Medetomidine
6,25 mg/Kg. 0,09 mg/Kg.
9 min. 32 min. 120 min.
OG06 Ketamine Medetomidine
6,52 mg/Kg. 0,1 mg/Kg.
5 min. 34 min. 85 min.
OG07 Ketamine Medetomidine
7,14 mg/Kg. 0,12mg/Kg.
6 min. 37 min. 94 min.
OG04 Ketamine Medetomidine
6,25 mg/Kg. 0,1 mg/Kg.
5 min. 45 min. 63 min.
OG08 Ketamine Medetomidine
5,62 mg/Kg. 0,1 mg/Kg.
5 min. 39 min. 37 min.
OG09 Ketamine Medetomidine
6,6 mg/Kg. 0,11 mg/Kg.
5 min. 35 min. 99 min.
OG10 Ketamine Medetomidine
5,26 mg/Kg. 0,08mg/Kg.
5 min. 43 min. 83 min.
OG11 Ketamine Medetomidine
7,5 mg/Kg. 0,1 mg/Kg.
5 min. 44 min. 51 min.
OG12 Ketamine Medetomidine
5,33mg/Kg. 0,1 mg/Kg.
5 min. 35 min. 85 min.
OG12 (recapture)
Ketamine Medetomidine
7,14mg/Kg. 0,125mg/Kg.
6 min. 32 min. 97 min.
OG13 Ketamine Medetomidine
6 mg/Kg. 0,1 mg/Kg.
5 min. 34 min. 123 min.
OG14 Ketamine Medetomidine
8,3mg/Kg. 0,09 mg/Kg.
12 min. 36 min. 97 min.
A IT = Induction time: from drug injection to complete drug effect, B MT = Manipulation time: from complete drug effect until the animal was placed in the recovery kennel, C RT = Recuperation time: from the end of manipulation to the release of the animal
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The lack of Pampas cat trapping success suggests that there is some inherent behavior that makes this
species wary of enclosure traps and thus difficult to capture for collaring. Other capture attempts failed as
well in other parts of South America.
ACKNOWLEDGEMENTS
The Whitley Laing Foundation and the Rufford Foundation (“Rufford Small Grant”), the Roger
Williams Park Zoo (“Sophie Danforth Conservation Biology Fund”), the Cleveland Metroparks Zoo
(“Scott Neotropical Fund”), and Idea Wild funded this stage of the study.
We want to thank the Lihué Calel´s park rangers (Raul Milne, Miguel Romero, Gisella Muller and
Horacio Erasun) for their support and help during the fieldwork. To Dr. Jim Sanderson, who kindly
provided valuable equipment (traps and a computer) for this study and to Drs. Andrés Novaro, Susan
Walker, Marcelo Pessino, Alejandro Vila and Pablo Perovic for their help. To Dr. Claudio Chehébar
(National Parks Administration) for his cooperation and support in obtaining work permits and to Anibal
Parera and Mario Beade (Fundación Vida Silvestre Argentina) for the equipment (receiver and antennas)
facilitation and their helpful suggestions.
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Manuscript in press - Journal of Mammalogy 87(6)
NUMERICAL AND SPATIAL RESPONSES OF GEOFFROY’S CAT (Oncifelis geoffroyi) TO A
SEVERE DECLINE IN PREY ABUNDANCE IN THE MONTE DESERT, ARGENTINA
Javier A. Pereira (1,3), Natalia G. Fracassi (1,3), and Marcela M. Uhart (2,3)
(1) Asociación para la Conservación y el Estudio de la Naturaleza – Iberá 1575 8vo. "B", Buenos Aires (1429), Argentina.
(2) Field Veterinary Program, Wildlife Conservation Society – Estivariz 197, Puerto Madryn (9120), Chubut, Argentina
(3) “Gatos del Monte” Project – www.acen.org.ar/gatosdelmonte.html
ABSTRACT
We examined the numerical and spatial responses of Geoffroy’s cats (Oncifelis geoffroyi) to a strong decline in the abundance
of their main prey in central Argentina between April 2002 and November 2003. The second year of the study coincided with a
severe drought. European hare (Lepus europaeus) density declined from 24.6 ind/km2 during the pre-drought period to about
2.8 ind/km2 during drought. Small rodent biomass showed also the lowest level for the study area during the drought of 2002-
2003 (134.5 g/ha). During the pre-drought and drought periods, three males and one female, and one male and nine females
Geoffroy´s cats, respectively, were radiotagged and monitored. Home ranges for males of the pre-drought period averaged
202.8 ha ± 156.8 SD and that of the single female was 27.3 ha. During the drought period, two Geoffroy’s cats abandoned the
area and a female with a non-optimal body condition when initially captured was found dead few days later. Four females
occupied an average home range of 254.9 ha ± 254.1 SD. The home-range size of the single pre-drought female increased by
two times after the prey decline. No obvious change in mean daily distance traveled between both periods were observed.
Geoffroy´s cats predominantly used habitats of dense cover and avoided open habitats during the pre-drought period, but
expanded their home range and became more habitat generalist during the drought. Four kittens were recorded during the pre-
drought period, but recruitment apparently did not occur during the drought period. All monitored Geoffroy´s cats dispersed
and/or died due to starvation after the prey decline. Consequently, Geoffroy’s cat density dropped from 2.9 ind/10 km2 before
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the drought to 0.3 ind/10 km2 probably due to food scarcity. This is the first study to examine the spatial ecology and density of
a small wild cat species under nutritional (energetic) stress in South America.
INTRODUCTION
Many predator populations are limited by food availability, and their densities fluctuate with periodic
changes in prey abundance (Angerbjorn et al. 1999). In general, predator populations respond to changes
in prey availability either numerically or functionally. Whereas numerical response refers to absolute
changes in the number of individuals by changes in reproductive rates, survival, immigration, or
emigration, functional response refers to behavioral changes, such as switching to alternative prey
(Murdoch and Oaten 1975; Ward and Krebs 1985; Angerbjorn et al. 1999). Strong variation in food
abundance might elicit one or both responses.
Models of optimal feeding vs. territory size predict that an animal's energetic needs and the density of
available food are important factors influencing home range size (McNab 1963; Mace and Harvey 1983;
Schoener 1983). An increase in home-range size of felids with low prey density has been observed on
temporal (i.e., Ward and Krebs 1985; Poole 1994; Norbury et al. 1998) or geographical scales (i.e.,
Edwards et al. 2001; Grigione et al. 2002). In general, when a prey base declines suddenly, home ranges
may shift or be abandoned altogether (Norbury et al. 1998; Edwards et al. 2001). In these situations,
increases in mortality and rates of emigration are also apparent (Poole 1994; Harper 2004).
In arid and semi-arid regions where water is a limiting resource, drought periods can have a strong
effect on the abundance and density of small rodents (i.e., Lima et al. 2003; Meserve et al. 2003) and
lagomorphs (Myers and Parker 1974; Palomares et al. 2001). Despite the frequency of these changes and
their importance in conservation planning, observational studies spanning them are relatively uncommon
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in South America, especially with predator responses over time (but see Jaksic and Simonetti 1987 and
Jaksic et al. 1997).
Geoffroy’s cat (Oncifelis geoffroyi) is a solitary, primarily nocturnal small felid, distributed from
southern Brazil and Bolivia throughout southern Patagonia in Argentina and Chile (Ximénez 1975;
Nowell and Jackson 1996). Little is known on the ecology of this species (Lucherini et al. 2004),
classified as “Near threatened” (Nowell 2002). It has been described as an opportunistic predator
(Canepuccia 1999) feeding mainly upon introduced European hares (Lepus europaeus) and small rodents
(Johnson and Franklin 1991; Vuillermoz and Sapoznikow 1998; Novaro et al. 2000). In southern Chile,
Johnson and Franklin (1991), in the only representative radiotelemetry study of the species, reported that
Geoffroy´s cats tend to use habitats with dense vegetation and probably high prey density.
Most of the Geoffroy´s cats´ range encompasses arid and semiarid environments (Ximénez 1975). In
central Argentina, where the species inhabits mainly shrublands and xeric forests, a severe drought
occurred in the summer of 2002-2003. This natural disturbance provided us with the opportunity to study
the effects of extreme conditions on the abundance of small- and medium-sized herbivores and its
consequences for Geoffroy´s cat density and spatial behavior.
Specifically, we focused on variations in home range size, habitat preference, daily movements, and
density of Geoffroy´s cats relative to changes in prey availability.
MATERIALS AND METHODS
STUDY AREA. The study was conducted in Lihue Calel National Park (37°57´S and 65°33´O, 9,900 ha)
and surrounding lands in La Pampa province, Argentina. This area is composed of flat terrain except for a
large, isolated set of bare rock hills. The vegetation is characterized by a mosaic of creosote bush flats
(Larrea spp., hereafter “jarilla” scrubland), grasslands mainly bunch grasses (Stipa spp.), and mixed shrub
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patches (e.g., Condalia microphylla, Prosopis flexuosa). There are some ephemeral ponds, but no
permanent surface water exists in the study area.
Five sigmodontine rodents, two hystricognath rodents (cavies) and the European hare (Lepus
europaeus) form the bulk of the Geoffroy´s cat's diet in the area (J. Pereira, unpublished data). The plains
vizcacha (Lagostomus maximus), a large herbivorous rodent preyed upon by Geoffroy´s cat (Branch
1995), disappeared from the region in 1998. The pampas fox (Pseudalopex gymnocercus), the pampas cat
(Lynchailurus colocolo), the jaguarundi (Herpailurus yaguaroundi) and the puma (Puma concolor) are
potential competitors of Geoffroy´s cats in the area.
Mean daily temperatures are <8ºC in winter and >25ºC in summer. Annual rainfall is 498 mm (SD ±
141, period 1986-2002), 72% of which (range 63–82%) is concentrated within spring and summer
(October-March). The amount of rain from October 2002 through March 2003, however, was markedly
lower (148.7 mm) than the seasonal average, resulting in a prolonged drought until November 2003 (data
from Lihue Calel weather station).
PREY AVAILABILITY. European hares were counted seasonally between the fall (April-May) of 2002
and the spring (October-November) of 2003, along a fixed transect of 15.6 km traversing the main
vegetation communities in the study area. Spotlighting counts were conducted by vehicle after sunset, 2-5
times per season. Because dense vegetation obstructed hares visibility, we used the Strip Transect method
to estimate density (Burnham et al. 1980). Strip width was fixed as the mean diameter in which hares
could be correctly detected times two. The area covered by each sampled transect was 187 ha.
A rodent survey was initiated in the winter of 2003 (drought period). The density and biomass of
sigmodontine rodents were determined in the jarilla scrubland, the main vegetation type in the study area.
Trapping was carried out by installing two 7 x 8-grids of aluminium live traps (Sherman Traps Inc.,
Florida, USA) spaced 10 m apart. The grids were operated for 5 consecutive nights using rolled oats and
peanuts as bait. Captured individuals were identified to species, weighed, individualized (by natural
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marks, color markers or, as the last option, toe-clip), and released at the capture site. Rodent abundance
was estimated based on the minimum number of individuals known to be alive (MNKA), and the density
was calculated as the ratio between the abundance and the area occupied by the grid. Small rodent
biomass was estimated as a product of the density and mean body mass of the individuals captured during
this study. Biomass values were then compared with those obtained by S. Heinonen (National Parks
Administration, unpublished report) during the winter of 1993, the only previous study conducted in the
area during a non-drought period. A new rodent survey was done in winter 2004 (after the drought),
following the same protocol as in 2003.
GEOFFROY´S CAT CAPTURES. Trapping was conducted in April 2002 (pre-drought period, trapping
effort: 224 trap-nights) and May 2003 (drought period, 440 trap-nights) with Tomahawk live traps baited
with domestic pigeons. Captured individuals were immobilized with ketamine and medetomidine
administered intramuscularly (average dose: 6 mg/kg and 0.1 mg/kg, respectively). Geoffroy´s cats were
sexed, weighed, measured, and aged (based on a physical examination and tooth eruption patterns).
Individuals >2.0 kg were fitted with radiocollars (Advanced Telemetry Systems, Isanti, Minnesota).
During the pre-drought and drought periods, 42-g M1940 radiocollars with internal antenna and 60-g
M1950 radiocollars with external antenna, respectively, were used. These radiocollars represented on
average 1.1% (range 0.9 – 1.5) and 2.2% (range 1.6 – 3.0) of the cats´ body weight. Each animal was
released at the capture site once it had recovered from anesthesia. The manipulation and care of animals
involved during this study followed guidelines approved by the American Society of Mammalogists
(Animal Care and Use Committee 1998) and by the Argentine Society for the Study of Mammals.
HOME RANGE AND MOVEMENTS. The locations of Geoffroy´s cats were obtained by triangulation from
the ground (White and Garrott 1990), using a hand-held 5-element Yagi antenna (Wildlife Materials,
Carbondale, Illinois) or an H-antenna (Telonics, Mesa, Arizona) and a portable receiver (TR-4, Telonics,
Mesa, Arizona). Locations were plotted on a 1:30,000 satellite image of the study area using Universal
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Transverse Mercator (UTM) coordinates. Visual sighting of radiocollared animals georeferenced using a
Garmin E-Trex Legend GPS (Garmin International Inc., Olathe, Kansas) were also included in the
analysis of home range sizes. Individuals were located 1 to 5 times per week, at daytime and night-time.
In most (79%) instances, the distance between the observer and the monitored animals was <260 m (total
range: 58–831 m).
Home range size was estimated using the Minimum Convex Polygon (MCP, Mohr 1947) and the
Adaptive Kernel (AK, Worton 1989) methods in the CALHOME software package (Kie et al. 1996). The
MCP is relatively robust with low sample sizes (Harris et al. 1990) and is the most commonly used
technique for estimating the home-range size of cats. We report the 100% MCP to allow comparison with
the Johnson and Franklin (1991) study. The AK are not influenced by effects of grid size and can estimate
densities of any shape (Seaman and Powell 1996). We calculated the 50% AK (as an area of core
utilization) and the 95% AK (as a commonly referenced contour) with a level of smoothing selected by
least-squares cross-validation and a grid cell size of 30 m x 30 m. Due to the low number of evaluated
individuals and the high variability in the home range sizes, no statistical analysis could be performed on
the home range data.
Independence of locations was assumed by taking only one location within a 24 h period interval
(Swihart and Slade 1985). The minimum number of locations needed to adequately describe home-range
size was estimated by plotting home-range sizes against the number of fixes to determine if this parameter
reached an asymptote (Harris et al. 1990). Home range overlap were calculated by averaging percentage
overlap between pairs of 100% MCP ranges.
Daily movements were calculated by measuring the linear distance between consecutive 24-h
radiolocations (Rabinowitz 1990; Poole 1994). This parameter was considered as an indicator of the time
and effort spent searching for prey (Brand et al. 1976; Ward and Krebs 1985; Poole 1994). Differences
between years were evaluated with t-test.
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HABITAT USE. We defined our study area by obtaining the 100% MCP of all independent locations for
all Geoffroy´s cats. We developed a Geographic Information System of this area (9,572 ha) based on
vegetation information obtained from 5 random transects crossing the area and from a LandSat 7 TM
satellite image (bands 3, 4 and 5) from January 2002. We performed a supervised classification using the
maximum likelihood decision rule (Lillesand and Kiefer 1994) and ERDAS IMAGINE 8.2 software.
Locations of each Geoffroy’s cat were digitized and converted as a layer using ARCVIEW 3.2/Thematic
mapper.
Habitat use was investigated at one scale of selection, defined as the selection of a home range within a
study area (second-order selection, Johnson 1980). We considered distinct vegetation types as different
habitat types (jarilla scrubland, mixed scrubland, dense grassland, xeric forest, and others). Each
Geoffroy´s cat location was assigned one habitat type. A chi-square goodness of fit test was used to
determine if the observed frequencies of habitat use differed significantly from expected frequencies
based on habitat availability (Neu et al. 1974; McClean et al. 1998). The null hypothesis tested was that
usage occurs in proportion to availability considering all habitats simultaneously (Neu et al. 1974).
Following a chi-square test, we used a Bonferroni correction of the z-statistic (α = 0.10) to maintain an
experiment-wise error rate (Miller 1981) and to create a normal approximation of the confidence intervals
to determine which habitat types were either selected, avoided, or neither. This is the most common test of
habitat use (McClean et al. 1998) and has been widely used in felid studies. Notwithstanding this, we
know that we violate the assumption of independence of observations within and among individuals (cf.
Alldredge and Ratti 1986). However, the small sample of monitored individuals precluded their use as
experimental units (Aebischer et al. 1993).
Because few locations were obtained on many animals, data were pooled for all males during the pre-
drought period and for all females (except female OG04) during the drought period in order to compare
17
habitat preference between both periods. Habitat preference of female OG04 was analyzed separately
because we obtained a large number of locations for her.
GEOFFROY´S CAT DENSITY. Minimum Geoffroy´s cat density was calculated seasonally between fall
2002 and spring 2003 based upon radiocollared cats in addition to the number of unmarked individuals
using the 9,572-ha study area, as estimated by visual sightings (Poole 1994; Franklin et al. 1999;
Palomares et al. 2001). Of the unmarked individuals, the only ones considered were those that could be
positively identified as different individuals, based on sighting location, body size, color patterns, or other
characteristics. As a result, density estimates were conservative and should be considered minimum
values (Poole 1994).
RESULTS
PREY ABUNDANCE. Hare density was high between fall and spring 2002 (pre-drought), peaking at 24.6
ind/km2 in winter. Density began to decline progressively until fall 2003, when it dropped to 2.8 ind/km2
and remained low (<3.5 ind/km2) through spring 2003 (Fig. 1). This represented a decline in hare density
of >88% in 9 months.
Rodent biomass estimated during the drought period was 66% lower (134.5 ± 89.2 g/ha, Fig. 2) than
that estimated for a non-drought period (S. Heinonen, National Parks Administration, unpublished report).
Whereas seven rodent species were captured during the non-drought period, only two species were
captured during the drought. However, because of the long time period between the two rodent surveys,
causes other than the drought (e.g., succession) may have been responsible for the observed species loss.
On the other hand, the recovery of the rodent community after a normal rainy season was notable; the
average biomass increased to 306.1 ± 35.5 g/ha in winter 2004 (Fig. 2).
18
FIG. 1. Density (Mean ± SD) of European hares (Lepus europaeus) by season (FL = Fall, WN = Winter, SP = Spring, SM = Summer) in Lihue Calel National Park, Argentina.
16.6
24.6
12
2.83.4 2.6
15.4
1
6
11
16
21
26
FL02 WN02 SP02 SM03 FL03 WN03 SP03Season
Hare
s de
nsit
y (I
nd /
km2
)
FIG. 2. Biomass (Mean ± SD) of small rodents in different winters (WN) in Lihue Calel National Park, Argentina.
393.1
134.5
306.1
0
100
200
300
400
500
600
WN93 WN03 WN04
Season
Rodent biomass (g / ha)
Although the density of cavies (Microcavia australis and Galea musteloides) was not evaluated during
the study, visual sightings recorded while travelling the study area suggested that their abundance also
decreased considerably during the drought.
CAT CAPTURES AND RADIOTRACKING. During the pre-drought period (2002) and the drought period
(2003), four (three males and one female, all adults), and ten (one adult male, eight adult females and one
subadult female) Geoffroy´s cats were captured and radiocollared. One additional male (in 2002) and two
additional females (in 2003) were also captured, examined and released without collaring due to poor
19
physical condition or equipment restrictions. Although in 2002 only one individual was recaptured (an
old, dehydrated male), five females were recaptured in 2003. Female OG04 was captured and monitored
during both the pre-drought and drought periods. Adult males outweighed adult females (3.96 ± 0.53 vs
2.83 ± 0.28 kg, t-test, p < 0.05) and were larger (body length; 925.2 ± 39.3 vs 838.5 ± 29.9 mm, t-test, p <
0.05).
The four pre-drought individuals were monitored an average 146.3 days (range 77-280). The tracking
period ended for the three males due to long-distance dispersal (>10 km), and for female OG04 because
of transmitter failure.
During the drought period, two Geoffroy’s cats abandoned the area shortly after captured (the only
radiotagged male dispersed 138 km) and the subadult female with a non-optimal body condition when
initially captured was found dead; she had lost >15% of body weight in this time. Three females moved
out of the home range that they had maintained for 39, 42, and 43 days and were found dead 1-2 days
later at 11.3, 5.8 and 9.6 km, respectively, from capture points. Another three females died within their
home ranges after 16, 17, and 54 days of being collared. Necropsies were conducted on five of these cats,
and the deaths were attributed to starvation. The remaining female was killed by another felid (probably a
jaguarundi [Herpailurus yaguaroundi] or another Geoffroy’s cat, based on feces found at the death site
and teeth marks found on the dead female’s neck); also, she showed signs of starvation. The radio signal
of female OG04 ceased after 1 month of radiocollaring for the second time and we were unable to find her
thereafter.
HOME RANGE AND MOVEMENTS. An asymptotic home range was not obtained for 3 females with <12
locations, all of them during the drought period, and they were not considered reliable estimates. Thus,
these animals were not included in home-range analysis.
20
During the pre-drought period, the average home range (100% MCP, mean ± SD) of males was 202.8
± 156.8 ha whereas the home-range size of female OG04 was 27.3 ha (Table 1). The areas used by males
OG01 and OG02 were contiguous and non-overlapping. After the prey decline, the mean home range size
of females was 254.9 ± 254.1 ha (Table 1). The home range size of female OG04 was two times larger
than that during the pre-drought period. Three cases of home range overlap were found during the drought
period between females OG07-OG09 (17.3%), OG13-OG14 (15.7%), and OG04-OG07 (1.4%).
TABLE 1. Home range of Geoffroy´s cats radiocollared during the pre-drought (year 2002) and drought (2003) periods in Lihue Calel National Park, Argentina. Total home ranges were estimated as the 100% minumum convex polygon (MCP) and the 95% adaptive kernel (AK) and core areas as the 50% adaptive kernel.
Home range size
(in hectares) Cat Id Period tracked No. of
fixes Asymptote
reached 100%MCP 95%AK 50%AK
M OG01 Pre-drought 02Apr – 18Jun 24 Yes 371.1 834.8 178.5 M OG02 06Apr – 09Jul 18 Yes 60.8 96.4 23.3 M OG03 07Apr – 19Aug 25 Yes 176.5 268.1 73.1 F OG04 07Apr – 12Jan 70 Yes 27.3 26.8 5.1 F OG07 Drought 11May – 20Jun 26 Yes 130.1 217.1 12.5 F OG04 13May – 13Jun 18 Yes 52.5 87.5 6.1 F OG08 15May – 28Jun 8 No 270.7 474.7 124.5 F OG09 16May – 28Jun 23 Yes 214.0 427.1 100.4 F OG12 23May – 17Jul 28 Yes 622.9 617.7 181.5 F OG13 25May – 10Jun 10 No 34.1 118.4 17.0 F OG14 25May – 11Jun 11 No 101.9 245.4 5.6
Although 95% AK home range estimates were in average 1.5 times larger than 100% MCP estimates
(Table 1), the inter-annual trend were in general similar with both methods.
The average core area (50% AK, mean ± SD) of males of the pre-drought period was 70.0 ± 77.8 ha
(range 5.1 – 178.5), whereas those of the females of the drought period was 75.1 ± 82.9 ha (range 6.1 –
181.5; Table 1). These values indicate how little of the home range (22.9 ± 3.6% and 16.4 ± 11.8% of the
95% AK during the pre-drought and the drought periods) was used intensively. No cases of core area
overlap between individuals were found.
21
Geoffroy´s cats were located on consecutive days 38 times during the pre-drought period and 52 times
during the drought period (Table 2). Non-significant differences (t = -0.44, d.f. = 65, P = 0.66) were found
in mean daily distance traveled between males of the pre-drought period and females of the drought
period. All females with a body weight of >3 kg showed average daily movements of more than 1 km. If
only these three females with body weight similar to those of the pre-drought males are considered, daily
distance traveled showed again non-significant differences (t = 1.79, d.f. = 40, P = 0.08). Female OG04
exhibited greater daily movements during the drought (Table 2), but differences between years were non-
significant (t = 1.63, d.f. = 32, P = 0.11).
TABLE 2.– Average daily distance travelled (in meters) by Geoffroy´s cats during the pre-drought and drought periods in Lihue Calel National Park, Argentina.
Pre-drought Drought n Mean ± SD Range n Mean ± SD Range Males 15 750.1 ± 460.3 17.0 – 1473.6 - - - Females - - - 52 850.1 ± 832.2 12.7 – 3757.8 Female OG04 23 240.0 ± 153.8 11.7 – 578.9 11 370.5 ± 318.2 36.1 – 896.3
HABITAT USE. The most abundant habitat type in the study area was the jarilla scrubland (59.2%),
followed by dense grassland (23.8%), mixed scrubland (8.8%), xeric forest (0.7%) and others (7.7%,
including rocky terrain, open grassland and bare soil). During both pre-drought and drought periods,
Geoffroy´s cats (except female OG04) mainly used jarilla scrubland, dense grasslands, and mixed
scrubland (Table 3). However, the former habitat type was used less than expected by chance in both
periods. Open habitats (grouped under "others") were used less than expected by chance during the pre-
drought period (Table 3). Female OG04 used predominantly xeric forest during the entire study period.
This habitat type was used more than expected and the jarilla scrubland was used less than expected in
both pre- and drought periods (Table 4). The frequency of mixed scrubland use changed between pre-
22
drought and drought periods, being avoided during the former and used as expected by chance during the
later (Table 4).
TABLE 3.– Chi-square test and Bonferroni Z-test 95% Confidence Intervals of habitat preference by Geoffroy’s cats (except female OG04) during the pre-drought and drought periods in Lihue Calel, Argentina.
Habitat type Availability
(prop.) Observed locations (prop.)
Bonferroni 95% Confidence
Intervals
Selection
Pre-drought period Jarilla scrubland 0.592 0.423 0.264 ≤ p ≥ 0.582 Avoid Mixed scrubland 0.088 0.173 0.051 ≤ p ≥ 0.295 Grassland 0.238 0.366 0.209 ≤ p ≥ 0.521 Xeric forest 0.007 0.019 -0.025 ≤ p ≥ 0.064 Other 0.075 0.019 -0.025 ≤ p ≥ 0.064 Avoid χ² Statistic 13.199 d.f. 4 P 0.010
Drought period Jarilla scrubland 0.592 0.462 0.349 ≤ p ≥ 0.575 Avoid Mixed scrubland 0.088 0.132 0.056 ≤ p ≥ 0.209 Grassland 0.238 0.340 0.233 ≤ p ≥ 0.447 Xeric forest 0.007 0.028 -0.009 ≤ p ≥ 0.066 Other 0.075 0.038 -0.005 ≤ p ≥ 0.081 χ² Statistic 18.787 d.f. 4 P <0.001
TABLE 4.– Chi-square test and Bonferroni Z-test 95% Confidence Intervals of habitat preference by Geoffroy’s cat OG04 during the pre-drought and drought periods in Lihue Calel, Argentina.
Habitat type Availability
(prop.) Observed locations (prop.)
Bonferroni 95% Confidence
Intervals
Selection
Pre-drought period Jarilla scrubland 0.592 0.100 0.017 ≤ p ≥ 0.183 Avoid Mixed scrubland 0.088 0.014 -0.019 ≤ p ≥ 0.047 Avoid Grassland 0.238 0.257 0.136 ≤ p ≥ 0.379 Xeric forest 0.007 0.586 0.449 ≤ p ≥ 0.723 Prefer Other 0.075 0.043 -0.013 ≤ p ≥ 0.099 χ² Statistic 3383.119 d.f. 4 P <0.001
Drought period Jarilla scrubland 0.592 0.262 0.028 ≤ p ≥ 0.498 Avoid Mixed scrubland 0.088 0.053 -0.067 ≤ p ≥ 0.172 Grassland 0.238 0.158 -0.037 ≤ p ≥ 0.353 Xeric forest 0.007 0.474 0.207 ≤ p ≥ 0.740 Prefer Other 0.075 0.053 -0.067 ≤ p ≥ 0.172 χ² Statistic 595.535 d.f. 4 P <0.001
23
GEOFFROY’S CAT DENSITY. At the beginning of the study Geoffroy’s cat density was estimated to be
2.6 ind/10 km2. Numbers remained high (>2.3 ind/10 km2) until the summer 2003 and declined
progressively to about 0.3 ind/10 km2, during periods of food scarcity (Fig. 3). Despite extensive search,
no Geoffroy’s cat kittens were found during the drought period, while during the pre-drought period at
least four kittens were recorded. Similarly, we did not detect follicles in ovaries or pregnancies in
necropsied females during the drought.
FIG. 3.– Density of Geoffroy’s cats by season (FL = Fall, WN = Winter, SP = Spring, SM = Summer) in Lihue Calel National Park, Argentina.
1.9
2.62.9
2.52.3
0.4 0.30
0.5
1
1.5
2
2.5
3
3.5
FL02 WN02 SP02 SM03 FL03 WN03 SP03Season
Cat density (Ind / 10 km2)
DISCUSSION
Our results indicate that before the drought, male Geoffroy´s cats were sedentary, occupying home
ranges up to 4 months before abandoning them. Similar behavior was reported by Johnson and Franklin
(1991) in southern Chile, where male Geoffroy’s cats dispersed >25 km from a home range that they had
maintained for 3-5 months. The home range sizes of all collared cats in the present study (except for
female OG12) were markedly smaller than those reported by Johnson and Franklin (1991) for both sexes.
Body weights of males and females in the present study were on average 18 and 33% lighter than those of
24
males and females in Johnson and Franklin (1991) study. This could explain the differences in home
range sizes between sites since in general this parameter scales allometrically with body size (McNab
1963; Harestad and Bunnell 1979; Mace and Harvey 1983; but see also Grigione et al. 2002). The
estimated prey density reported by Johnson and Franklin (1994) allow us to reject the prey availability
hypothesis to explain home range size differences between sites, given that actually prey density at the
Chilean site (mean hare density = 86.6 inv/km2 and mean rodent density = 62.2 ind/ha) was much greater
than that at our study area.
In Lihue Calel, Bonaventura et al. (1998) found a positive correlation between small rodent biomass
and vegetation complexity, suggesting that vegetation plays an important role in structuring rodent
communities in this area. Although quantitative data are lacking, severe drought in our study area resulted
in the vegetation becoming markedly more sparse and insects less abundant (personal observations), and
these changes may have been the driving force behind the decline in rodent biomass. The reduction in the
herbaceous layer probably also triggered the decline of European hare density as they are herbivorous
(Campos et al. 2001). A similar situation was described during drought periods in Lihue Calel for the
vizcacha, a native herbivore of similar body weight (Branch et al. 1994). It is also possible that some
hares were actually more vulnerable to predators due to the lack of foliage cover (cf. Brown 1988).
The increase in capture success of Geoffroy´s cats during the drought period may be due to felines
becoming more inclined to investigate traps during periods of low food availability. Poor body condition
of captured and necropsied individuals during the drought period further supports the importance of food
scarcity.
Bailey (1981) and Ward and Krebs (1985) reported that bobcats (Lynx rufus) and lynx (Lynx
canadensis) that defended territories during periods of prey abundance became nomadic when prey
declined. These authors suggest that if prey density is unpredictable or very low, it would be adaptive for
these cats to become transient and search out widely separated concentrations of prey. In the present
25
study, during the period of prey scarcity, two Geoffroy’s cats abandoned the area a few days after being
radiocollared, but it is unclear if this was a behavioral response to declining prey abundance or if they
were transient animals without stable territories. In one month, four female cats monitored during the
drought occupied an average home range greater than those occupied by males during two to four months
in the pre-drought period. Previous studies on small felids showed that males home ranges are
substantially larger than those of females (i.e., Konecny 1990; Grassman 2000). For Geoffroy´s cats,
Johnson and Franklin (1991) reported a similar pattern, with adult males occupying home ranges more
than twice as large as those of adult females. Based on these two trends, it follows that female Geoffroy´s
cats may have responded to declining prey abundance by expanding their home ranges, because they
exceeded the home range size of males estimated for the pre-drought period. In support of this idea,
female OG04 doubled the size of her home range between the pre-drought and drought periods.
The movement patterns of predators have been observed to increase if prey abundance declines or prey
becomes less detectable (Knowles 1985; Ward and Krebs 1985; Sunquist and Sunquist 1989). In
agreement with these observations, the daily distance traveled by female OG04 increased once prey
declined (non significant differences may be product of the small sample size), and those of females
monitored during the drought period were greater than those of males monitored during the pre-drought
period. These results suggest that Geoffroy´s cats increased the time and effort spent in search for prey to
fulfill their energetic needs.
Despite drought-related environmental changes, little variations in habitat use were found between pre-
drought and drought periods. However, comparisons between both periods should be considered carefully
because they involve different individuals. Previous studies conducted on small felids (i.e., Dunstone et
al. 2002; Harper 2004) have reported interindividual differences in habitat use. Johnson and Franklin
(1991) reported that Geoffroy´s cats predominantly used areas of dense cover because they provide higher
prey availability and protective cover. Our results support this findings during the pre-drought period,
26
when Geoffroy´s cats used habitats of dense cover (such as xeric forest and dense grassland) and avoided
open habitats. When prey species became scarcer, Geoffroy´s cats responded by expanding their home
range to increase opportunities for encountering prey. As a result, habitats avoided during the pre-drought
period such as mixed scrubland and open habitats (i.e., rocky terrain, open grassland) changed their
frequency of use, being used in proportion to availability during the drought period.
Six radiocollared Geoffroy’s cats died due starvation during the drought period and these effect
occurred with a hare density of <3.5 ind/km². A critical level for rodent abundance could not be
determined due to a lack of rodent surveys during the decline period. As a result, Geoffroy’s cat density
dropped from 2.3 ind/10 km² to 0.4 ind/10 km² between the summer and winter 2003, with a mortality
peak between June and July. A similarly elevated mortality rate within a 1-2 month period was reported
by Edwards et al. (2001) for feral cats (Felis catus), during a period of prey scarcity in a semiarid area of
Australia. Only a few individuals were present in the study area by the spring of 2003, but whether they
were the surviving uncollared animals of the study population or immigrants is unknown.
The absence of kitten recruitment for Geoffroy´s cats during the prey decline is consistent with that
observed for other felid species (Nellis et al. 1972; Brand et al. 1976; Knick 1990; Mowat 1993; Poole
1994). Lack of body fat and emaciation were common findings for all dead animals and it is well-known
that undernutrition negatively affects sexual activity (i.e., Gill and Rissmann 1997; Schillo 1992; Wade et
al. 1996). Body condition can also affect animal’s immunity, rendering them more susceptible to
opportunistic pathogens (Ullrey 1993; Lloyd 1995; Hulsewe et al. 1999). However, no evidence of
clinical infectious disease was found in the necropsied cats, though parasite loads were very high in most
individuals (Beldoménico et al., in press). We did not find additional evidence of disease-related
mortality, such as observation of sick animals or epidemic-type simultaneous deaths.
Based on the observed decrease in the abundance of preferred prey species, the exploitation of an
alternative food source (prey-switching) by Geoffroy´s cats might have been expected. This kind of
27
behavioral response during prey scarcity has been reported in other felids such as the puma (Pessino et al.
2002) and the Iberian lynx (Lynx pardinus-Beltran and Delibes 1991). Johnson and Franklin (1991) and
Canepuccia (1999) also reported prey-switching by Geoffroy´s cat following seasonal changes in prey
abundance. In Lihue Calel, potential alternative prey for Geoffroy’s cat, such as armadillos (Zaedyus
pichyi and Chaetophractus villosus), the mara (Dolichotis patagonum) or the elegant crested-tinamou
(Eudromia elegans), were relatively uncommon (Lihue Calel National Park – Conservation Value Species
Register, Period 1995-2004; and personal observations) and, although they were not monitored during the
study period, their abundance was likely lower during the drought. Other vertebrate taxa, such as
amphibians and reptiles, constitute a seasonal food resource virtually unavailable during the colder winter
months. As a result, potential alternative prey may have been insufficient at a local scale to allow
Geoffroy´s cats to fulfill their energetic requirements, and that may have contributed to the increased
mortality and emigration.
Before its extinction from Lihue Calel, the vizcacha may have been important prey for Geoffroy´s cats
(Branch 1995). During events of decline in small rodents and hares, the vizcachas could have constituted
a key resource for Geoffroy´s cat survival, as they are large rodents which live in fixed communal burrow
systems, thus providing a spatially predictable resource for predators (Branch 1995). On the other hand,
replacement of native by introduced prey in predator diets appears to be widespread in southern South
America and the European hare has become an important component of the Geoffroy's cat diet (Novaro et
al. 2000). More research is required to understand the dynamics of interactions between this predator and
its native and introduced prey species and how climate affects this chain of trophic interactions.
ACKNOWLEDGEMENTS
28
We thank H. Ferreyra, M. Romero, G. Müller, F. Gallego, C. Rozzi Giménez, A. Hurtado, P.
Gramuglia, D. Muñoz, V. Coronel, C. Marull, P. Teta, P. Rossio, J. de Estrada, D. Ugalde, and J. Gato for
their dedicated fieldwork; R. Milne, P. Erasun, C. Toledo, A. Iriarte, G. Aprile, and D. Varela for their
logistical support and field assistance; J. Sanderson, A. Novaro, S. Walker, P. Perovic, D. Villarreal, A.
Parera, M. Beade, K. Schiaffino, A. Vila, L. Maffei, M. Pessino, and A. Sosa for the equipment and
assistance provided; S. Heinonen for supplying her unpublished information; and C. Figueroa for the
English translation. D. Villarreal, A. Noss, S. Walker, J. Sanderson, John Yunger, and anonymous
reviewers provided constructive comments.
This study was supported by the Asociación para la Conservación y el Estudio de la Naturaleza, the
WCS–Field Veterinary Program, the Cleveland Metroparks Zoo (Scott Neotropical Fund), the Roger
Williams Park Zoo and Rhode Island Zoological Society (Sophie Danforth Conservation Biology Fund),
the Rufford Foundation and Whitley Laing Foundation (Rufford Small Grant) and Idea Wild.
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Acta Parasitologica (2005) 50: 263–266
HELMINTHS OF GEOFFROY’S CAT, Oncifelis geoffroyi (CARNIVORA, FELIDAE) FROM
THE MONTE DESERT, CENTRAL ARGENTINA
Pablo M. Beldomenico (1,2), John M. Kinsella (2), Marcela M. Uhart (3,5), Gabriela L. Gutierrez (1),
Javier A. Pereira (4,5), Hebe del V. Ferreyra (3,5) and Carolina A. Marull (3,5)
(1) Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral, RP Kreder 2805 (3080) Esperanza, Argentina.
(2) HelmWest Laboratory, 2108 Hilda Avenue, Missoula, MT 59801, U.S.A.
(3) Field Veterinary Program – Wildlife Conservation Society, Estivariz 197, Puerto Madryn (9120), Argentina
(4) Asociación para la Conservación y el Estudio de la Naturaleza, Iberá 1575 8° B, Buenos Aires, Argentina
(5) “Gatos del Monte” Project - www.acen.org.ar/gatosdelmonte.html
ABSTRACT
Gastrointestinal parasites were collected from 7 free-ranging Geoffroy’s cats (Oncifelis geoffroyi) from Lihué Calel National
Park, Argentina. Also, fecal samples were analyzed from these animals and 3 other sympatric ones. The helminths were
identified as Vigosospirura potekhina, Didelphonema longispiculata, Pterygodermatites cahirensis, Trichuris campanula,
Ancylostoma tubaeforme, Toxocara cati, and Taenia sp. Fecal analysis revealed the presence of eggs of Capillaria sp. and an
unidentified anoplocephalid tapeworm, and coccidian oocysts. The findings of V. potekhina, D. longispiculata, P. cahirensis,
and T. campanula represent first records of these species in O. geoffroyi. Further, the former three had never been reported in
South America.
Stefañski
Information on the helminths of Neotropical felids is scarce. Although 10 of the 12 existing wild felids
of the Americas can be found in Argentina (Nowell and Jackson 1996), there are few reports of these
carnivore parasites in that country. One of the most widespread species in southern South America is the
37
Geoffroy’s cat, Oncifelis geoffroyi (d’Orbigny et Gervais, 1844), which can be found from southern
Brazil and Bolivia throughout southern Patagonia in Argentina and Chile. Although this species occurs in
a wide variety of habitat types, most of this cat’s range encompasses arid and semiarid environments
(Gomes de Oliveira 1994, Nowell and Jackson 1996). Like most other small wild cats of the region, the
biology of this species is poorly known. Its helminth fauna is one of the least explored topics.
In central Argentina, the Geoffroy’s cat population of Lihué Calel National Park (LCNP; 37°57´S
65°33´W, 9900 ha) is being studied by the “Gatos del Monte” project. This protected area, representing
the Monte Ecoregion, is composed of flat terrain except for a large, isolated set of bare rock hills (590 m
a.s.l.). The vegetation is characterized by a mosaic of creosote bush flats (Larrea sp.), grasslands (mainly
bunch grasses of Stipa spp.), and mixed shrub patches (Administratión de Parques Nacionales, Buenos
Aires, 1983). A severe drought occurred in 2003 in central Argentina. In some places such as the LCNP,
this was the most severe drought since 1965. As a result, six radio-collared adult female Geoffroy’s cats
were found dead between May-June 2003. Necropsies and parasite collection were conducted. Death was
tentatively attributed to starvation, which was later confirmed by histopathology. Additionally, in July
2004, an adult male cat was shot by a farmer near the park’s boundaries and it was necropsied to collect
parasites. A fecal sample had been previously taken from each dead cat and from three other sympatric
radio-collared cats. By previously described methods (Beldomenico et al. 2003), each section of the
gastrointestinal tract was searched for metazoan parasites, and fecal samples were preserved in 3.5%
formalin saline until analyzed at the laboratory by a sedimentation-flotation technique. Five of each
specific adult parasites or eggs were measured, and the measurements were reported as arithmetic mean
and standard deviation (SD). When fewer specimens were available for measuring, the range or the
unique value were reported.
38
Voucher specimens were deposited at the Colección de Parásitos de Vertebrados Silvestres of
Universidad Nacional del Litoral, Esperanza, Argentina (Acc. no: LP00016-LP00035). Our findings are
summarized in Table 1.
Fig. 1. Parasites recovered from necropsied Geoffroy’s cats from Lihué Calel National Park, Argentina: A– cestode egg, B – oral extremity of Vigisospirura potekhina, C – oral extremity of Didelphonema longispiculata, D – vulvar region of Trichuris campanula, E – oral extremity of Pterygodermatites cahirensis, F – caudal extremity of a male Pterygodermatites cahirensis. Scale bars = 25 µm
39
FECAL ANALYSIS.
Capillaria sp. eggs measuring 49.5 (SD = 2.6) × 37.9 µm (SD = 2.8) were detected in 4 of 9 fecal
samples. Eggs resembling Ancylostoma sp., measuring 65.6 (SD = 3.5) × 37.9 µm (SD = 2.8) were
detected in 2 of 9 fecal samples. Trichuris sp. eggs measuring 70.6 (SD = 5.7) × 32.2 µm (SD = 3.5) were
detected in 5 of 9 fecal samples. Eggs resembling Toxocara sp., measuring 74.4 (SD = 14.9) × 60.3 µm
(SD = 7.2) were detected in 1 of 9 fecal samples. Triangular cestode eggs with a pyriform apparatus
resembling those of Anoplocephalidae (Fig. 1A) were found in one sample. Immature coccidian oocysts
measuring 26.2 µm (SD = 1.7) were detected in 2 of 9 fecal samples. These findings are not different
from those reported for other Neotropical felids (Patton et al. 1986).
ADULTS.
Vigisospirura potekhina (Petrow et Potekhina, 1953) (Spirurida, Spirocercidae) (Fig. 1B): a total of 39
adult specimens was collected from the oesophagus and 11 from the stomach of 5 cats. The female:male
ratio (FMR) was 4.1. This spirurid parasitizes both felids (Wong et al. 1980, Torres et al. 1998) and
badgers, Meles meles (Torres et al. 2001) in the Old and the New World. This represents the first report of
the species in South America.
Didelphonema longispiculata (Hill, 1939) (Spirurida, Spirocercidae) (Fig. 1C): 160 adult specimens
were collected from the stomach of 2 of the cats. The FMR was 4.0. Although this New World parasite
has been found in marsupials and felids of North America (Stewart and Dean 1971, Pence and Eason
1980, Wong et al. 1980), very little has been published about its host-parasite relationships. This
represents the first report of the species in South America.
Pterygodermatites (Multipectines) cahirensis Quentin, 1969 (Spirurida, Rictulariidae) (Fig. 1E–F): a
single male of this species was found in the small intestine of one necropsied cat. The spicules measured
161 × 15 µm. This parasite is prevalent in canids from the Old and the New World (Young and Pence
1979). In the southern United States, it is commonly found in coyotes (Canis latrans) and less frequently
40
in bobcats (Lynx rufus) (Stone and Pence 1978). Although P. cahirensis is considered to be distributed in
carnivores worldwide (Young and Pence 1979), this is the first record from South America.
Table 1. Helminths collected from free-ranging Oncifelis geoffroyi from Lihué Calel National Park, Argentina
D. l
ongi
spic
ulat
a
P. c
ahir
ensi
s
Taen
ia sp
.
T. c
ati
T. c
ampa
nula
V. p
otek
hina
A. tu
baef
orm
e
Prevalence
2/7 1/7 3/7 6/7 3/7 5/7 2/7
Maximum intensity
146 1 37 57 52 24 5
Length femalesa x (SD)
7.1 (0.7)
NA NA 63.8 (10.5)
23.9 (8.2)
15.7 (2.5)
6.5-10.0
Length malesa x (SD)
3.9 (0.2)
3.3 NA 41.0 (3.7)
22.1 (2.5)
10.9 (0.3)
6.4 (0.4)
Eggs measuresb
31×15 NA 30.8×36.5 74.4×60.3 70.6×32.2 55.5×27.5 65.6×37.9
a in milimeters, b in micrometers, NA = Not available
Trichuris campanula Linstow, 1889 (Enoplida, Trichuridae) (Fig. 1D): 97 adult specimens were
collected from the large intestine of 3 cats. The FMR was 1.7. In males, the spicule measured 1065 µm
(SD = 105) and was contained within a spinous sheath. Until the late 1970’s, the findings of feline
whipworms in the New World were confined to South America and Cuba (Enzie 1951; Hass 1973, 1978).
To date, the only Trichuris sp. reported for domestic cats are Trichuris serrata Linstow, 1879 and
Trichuris campanula Linstow, 1889 (Urioste 1923, Clarkson 1960, Kelly 1973, Ng and Kelly 1975, Hass
and Meisels 1978). Both species were originally described from domestic cats from Brazil. Regarding
wild felids, there is only one record of a Trichuris sp. (named Trichocephalus) from a tiger-cat
41
(Leopardus tigrinus) in Brazil (Diesing 1851). Our finding constitutes the first record of T. campanula for
O. geoffroyi.
Ancylostoma tubaeforme (Zeder, 1800) (Strongylida, Ancylostomatidae): nine hookworms were found
in the small intestine of two Geoffroy’s cats. The FMR was 0.6. A. tubaeforme is a cosmopolitan
hookworm of cats (Anderson 2000). In the Neotropical region, it was reported for otter cat, Herpailurus
yagouaroundi; jaguar, Panthera onca (Thatcher 1971); and Argentinean O. geoffroyi (Martinez 1987).
The infection by this species may indicate interaction with domestic cats.
Toxocara cati (Shrank, 1788) (Ascaridida, Ascarididae): 211 specimens were collected from the stomach
and small intestine of 6 cats. The FMR was 3.25. This ascarid is a cosmopolitan parasite of felids,
including domestic cats and wild felids in the subfamilies Felinae and Pantherinae (Anderson 2000). This
species was found in association with Toxocara canis in free-ranging O. geoffroyi from northern
Argentina (Martinez 1987). The infection by this species probably represents interaction with domestic
cats.
Taenia sp. (Cestoda, Taeniidae): 3, 7 and 37 tapeworms of this genus were found in the small intestines
of 3 cats, respectively. The scolex diameter measured 524–620 µm, the rostellum diameter was 356–403
µm, and the suckers ranged from 201 to 248 µm. Total numbers of hooks ranged from 40 to 46; large
hooks were 165 to 170 µm long and small hooks 130 to 140 µm long. Eggs were typical of Taeniidae. For
South America, the only records of Taenia spp. of felids are Taenia omissa Lühe, 1910 from cougar
(Puma concolor), and Taenia macrocystis (Diesing, 1850) from O. geoffroyi, P. onca and H.
yagouaroundi (Verster 1969, Schmidt and Martin 1978). The number, size, and shape of the rostellar
hooks found here are quite different from T. omissa and T. macrocystis, as well as the common North
American taeniids of felids, T. taeniaeformis and T. rileyi. Hook size and shape seem closest to T.
hydatigena, but the size of the large hooks is at the extreme low end of the range for this species, which
has not been reported from South America (Loos-Frank 2000). It is possible the species found here is
42
undescribed and more study is warranted (Robert L. Rausch, pers. commun.). To date, the only cestode
reported for O. geoffroyi in Argentina was Echinococcus oligarthrus (Diesing, 1863), which was found in
animals from the same province as the present study (Schantz and Colli 1973).
The findings of V. potekhina, D. longispiculata, P. cahirensis, and T. campanula represent the first
records of these species in O. geoffroyi. Further, the former three had never been reported for South
America. Probably, this reflects lack of investigation rather than recent introduction of the parasites.
Infections with T. cati, A. tubaeforme and T. cf. hydatigena might be the result of interactions with
domestic cats.
ACKNOWLEDGEMENTS
This project was funded by The Rufford Foundation, The Whitley Laing Foundation, The Cleveland
Metroparks Zoo and The Rhode Island Zoological Society. We also thank the financial and institutional
support of Jim Sanderson (Conservation International), and the Field Veterinary Program, Wildlife
Conservation Society, Natalia Fracassi for sampling assistance, Leandro Antoniazzi and Luciana Camuz
Ligios for field support, and Dr. Robert L. Rausch for his opinion on the cestodes.
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45
Manuscript in preparation
HEALTH STATUS OF GEOFFROY’S CAT AT LIHUE CALEL NATIONAL PARK,
CENTRAL ARGENTINA
Marcela M. Uhart (1,3), Javier A. Pereira (2,3), Hebe del V. Ferreyra (1,3), and Carolina Marull (1,3)
(1) Field Veterinary Program, Wildlife Conservation Society (WCS)
(2) Asociación para la Conservación y el Estudio de la Naturaleza (ACEN)
(3) “Gatos del Monte” Project – www.acen.org.ar/gatosdelmonte.html
INTRODUCTION
Two phases of field work were carried out to capture wild cats with the intention of fitting radio collars
on a sample of individuals. This report presents complete results on health data obtained from the
collection of biomedical samples during this field work.
MATERIALS AND METHODS
Thirteen Geoffroy’s cats were successfully captured during the two phases of field work. Stress of
trapped cats was reduced by utilizing a shield which impeded the animal's vision of its surroundings.
Once tranquilized, the animals were anesthetized by intramuscular injection of a combination of ketamine
and medetomidine. After the injection, and during anesthesia induction (approx. 5-7 min.), the animal was
again isolated from external stimuli. The average dose of ketamine was 5.78 mg/kg. and that of
46
medetomidine was 0.97 mg/kg. The effects of medetomidine were reversed by the application of its
specific antagonist, atipamezol, starting 30 min. after the initial injection, at a dose of 0.5 mg/kg.
The anesthetized animals were weighed, sexed, and measured completing a morphometric record for
each individual. Blood samples were collected and refrigerated prior to their processing in the field (no
more than 4 hrs.). When recovery from anesthesia began (evidenced by movements, reflexes, etc.), the
animals were placed in a recovery kennel containing blanketing material to maintain the animal's body
temperature, and were protected from light and external stimuli. During this period, and until the animal
was released (upon total recovery from anesthesia) each individual was monitored at 30 min. intervals.
Each animal was released in the same location in which it was trapped, and was monitored continuously
during the next 24 hs by radiotelemetery. All anesthetic procedures were judged satisfactory for the
performed procedures and the animals recovered normally and without complications.
At the end of the second phase of the project, from May 31 to July 17, 2003, six radiocollared
Geoffroys’ cats (Oncifelis geoffroyi) were found dead. Complete necropsies were performed and samples
were submitted for histopathological analysis.
RESULTS
BASIC HEMATOLOGY. Basic hematology was performed in the field on samples obtained from the
captured O. geoffroyi. The results are shown in Table 1.
BLOOD BIOCHEMISTRY, ENZYMES, AND MINERALS. In Table 2, the medians and standard deviations of
the analyzed parameters are shown. The level of enzyme GGT was detected in only one individual,
OG13, with a value of 3 (UI/L). Direct bilirubin was undetectable by the test used, and was therefore not
included in the table.
47
Table 1. Basic hematology of wild O. geoffroyi.
Individual Sex Weight (kg)
White cell count (per mm3)
Red cell count (per mm3)
PCV Total Solids (g/dl)
OG01 M 4,7 19200 8.9 x 106 50 7.8 OG02 M 4,3 13200 7.6 x 106 35 10 OG03 M 3,9 10800 7.5 x 106 41 8.2 OG04 F 2,3 15700 7,9 x 106 42 8,4 OG05 M 3,2 20000 - - - OG07 F 2,4 - - 42 9 OG08 F 2,4 11100 8,6 x 106 42 9 OG09 F 3,0 11400 4,8 x 106 43,5 8,9 OG10 M 3,8 - 7,1 x 106 32,5 8,2 OG11 F 2,0 13600 7,16 x 106 37 7,8 OG12 F 2,9 18250 9,905 x 106 43 8,8 OG13 F 2,5 15900 7,12 x 106 30 8,5 OG14 F 3,0 7800 15,07 x 106 45,5 10
Table 2. Blood biochemistry, enzymes, and minerals of wild, free-ranging O. geoffroyi.
TEST (units) Median ± SD N
PCV 40.22 ± 5.65 12 White Cell Counts (cel /mm3 x 103) 12.63 ± 4.89 11
Red Cell Counts (cel /mm3 x106) 8.33 ± 2.58 11 Total Solids (g/dl) 9 ± 0.90 12
ALK (UI/L) 6 ± 7.43 6 ALT (UI/L) 17.87 ± 17.85 8 AST (UI/L) 113.87 ± 41.71 8 CK (UI/L) 2390.87 ± 1333.08 8
GGT (UI/L) 3 1 Albumin (g/dl) 2.26 ± 0.55 8
Total Proteins (g/dl) 6.6 ± 0.78 8 Globulin (g/dl) 4.33 ± 0.87 8
Relation Albumin/Globulin 0.52 ± 0.20 8 Total Bilirubin (mg/dl) 0.17 ± 0.11 5
Indirect Bilirubin (mg/dl) 0.14 ± 0.09 5 NUS (mg/dl) 52.37 ± 8.89 8
Creatinine (mg/dl) 0.78 ± 0.43 8 Cholesterol (mg/dl) 160.87 ± 53.64 8
Glucose (mg/dl) 82.87 ± 37,23 8 Calcium (mg/dl) 9 ± 0.78 8
Phosphorus (mg/dl) 5.3 ± 1.15 8 Bicarbonate (mEq/L) 15.62 ± 3.96 8
Chloride (mEq/L) 115.5 ± 4.37 8 Potassium (mEq/L) 3.54 ± 0.32 8 Sodium (mEq/L) 162 ± 4.07 8
Sodium/ Potassium 46.12 ± 4.79 8 Anion GAP (mEq/L) 34.5 ± 6.39 8
SEROLOGICAL TESTS FOR PARASITIC AND INFECTIOUS DISEASES. Serological analyses were carried out
for nine infectious diseases and two parasitic diseases: Feline leukemia (ViLef), Infectious feline
peritonitis (PIF), Feline immunodeficiency virus (VIF), Feline panleukopenia (PF), Canine distemper
48
(DC), Feline calicivirus (CVF), Feline herpes virus (HVF), Rabies (R), 5 serovares of Leptospiras (Lep),
Toxoplasmosis (To), and Dirofilariasis (Di).
All analyses were negative for ViLef, VIF, HVF, R, PF and Lep (serovars Pomona, Hardijo,
Icterohemorrhagiae, Grippotyphosa y Canicola). Ninety percent of the animals tested positive for CVF,
followed by 50% positive for To, 40% for DC, and 10% for PIF and for Di (Table 3).
Table 3. Parasitic and infectious diseases analyzed and serological tests performed for ten free-ranging Geoffroy’s cats from Lihue Calel National Park (Positive animals / total tested).
Infectious agent / disease Test Positive animals/total Feline leukemia ELISA 0/10
Feline immunodeficiency virus Wblot, KELA 0/10 Feline panleukopenia HI 0/10 Feline herpes virus SN 0/10
Rabies RFFIT 0/10 Leptospiras (5 serovares) MA 0/10
Infectious feline peritonitis KELA 1/10 Canine distemper SN 4/10 Feline calicivirus SN 9/10 Toxoplasmosis KELA 5/10 Dirofilariasis ELISA 1/10
Reference: MA: Micro-agglutination, Wblot: Western blot, HI: Hemagglutination inhibition, SN: Seroneutralization, KELA: kinetic ELISA, RFFIT: Rapid Flourescent Focus Inhibition Test
HISTOPATHOLOGICAL RESULTS. Macroscopic observations revealed severe emaciation in all of the dead
animals, with different degrees of parasitic (ecto and endoparasites) infestation. Histopathological results
showed degenerative changes in several organs which were compatible with progressive inanition and
death by starvation.
DISCUSSION
Hematological and blood biochemistry results were found to be within normal ranges published for
domestic cats (Felis catus) (Duncan 1986) and within values described for captive O. geoffroyi (ISIS
2004), while no other similar data were found in the literature which would permit a comparison.
49
Serological results from our study indicate that the O. geoffroyi from Lihue Calel National Park are
exposed to various pathogens common to domestic felids and canids.
The prevalence of Calicivirus (90%) indicates the presence of this infectious agent in the cat population
at Lihue Calel National Park. This virus is known for its extreme contagiousness, and causes high
morbidity and death rates close to 30% in young domestic cats (Gaskell and Dawson 1994), especially in
areas with a high feline population density such as zoos and breeding facilities. New strains of this virus
which produce high mortality in domestic cats have recently been detected (Pedersen et al. 2000); this
antigenic variability might pose a threat to wild felines. Transmission of the virus is by direct contact,
especially airborne contact as in the case of sneezing (Lenghaus et al. 2001). Though no data exists on
other wild populations of O. geoffroyi, the high population density observed in this protected area could
have increased the rate of contact between individuals, thus explaining its prevalence in the population.
Positive serological results have been reported in studies on various species of wild felines in America
and Africa, but to date clinical disease has not been reported for those populations (Lenghaus et al. 2001).
Clinical symptoms described in domestic cats and in captive felids such as lions, cheetahs, and Siberian
tigers are: fever, anorexia, lethargy, vesicles and erosions in the oral mucosa, and, usually, nasal and
conjunctival secretion (Love 1975, Kadoi et al. 1997). In our study, high levels of antibodies to calicivirus
were observed in most cases (3 animal with titers of 1:768), which would indicate an active response by
the animals to the virus. The lack of clinical symptoms in the sampled individuals, coupled with the
absence of the typical macro and microscopic lesions, suggests previous exposure to this agent and the
probability that it is endemic in the tested population.
The O. geoffroyi in our study showed a 40% prevalence of canine distemper virus. This morbillivirus
affects a wide range of domestic and wild carnivores and also marine mammals. The epidemoliogy of this
virus in wild species has not been thoroughly studied, although recent epidemics have been reported in
wild lions, causing mortality of up to a third of the population in the Serengetti ecosystem (Roelke-Parker
50
et al. 1996). The exact mode of transmission in felids is not well understood, but it is assumed that it
comes from other carnivores by way of contact with ocular or nasal secretions or by airborne transmission
(Munson 2001). Affected felines present digestive or respiratory symptoms which can progress to
neurological sickness and death (Appel et al. 1994, Roelke-Parker et al. 1996). In our study one of the
animals showed a high level of antibodies (1:2048), which could indicate recent exposure to the virus,
while the rest of the individuals had low antibody titres. The absence of clinical symptoms and lesions
typical of distemper suggests that the animals were not in an active phase of the disease, but indicates the
population's previous contact with the virus.
The sampled cats showed a 10% positive rate for Infectious feline peritonitis. This disease is caused by
a coronavirus to which domestic cats are susceptible. In a manner similar to calicivirus, transmission of
this virus is favored by close contact between animals. The low density of individuals in wild populations
limits its transmission, resulting in the low reported prevalence of this disease, about 2% in wild felid
populations (Everman and Benfield 2001). Exposure to feline coronavirus in large wild felines such as the
cheetah has been documented and could result from interaction with domestic cats, or from cross
reactions with other antigenically similar dietary coronaviruses, as a result of their feeding on feral swine
(Henny et al. 1990). A fatal form of the disease has been described in captive cheetahs (Heeney et al.
1990). This virus is not resistant in the environment and is transmitted via feces and respiratory
secretions. Even though this coronavirus is very species-specific cross-over infection has been
documented between domestic and wild felines, and between domestic and wild canines (Evermann et al.
1980, Ballou 1993, Cunningham 1996). The levels of antibodies found in our study are low and are
probably only indicative of exposure to the infectious agent.
For Toxoplasmosis (Toxolasma gondii) the seroprevalence was 50%. This parasitic disease is widely
distributed globally and affects a large number of both wild and domestic animals (Dubey and Beattie
1988, Dubey 1994), with felines being the end host. Infection with this agent is common in felids whereas
51
clinical symptoms are rare (Dubey et al. 1987), in view of which it does not represent a significant threat
to wild feline populations (Silva 2001). Consumption of infected prey is the most likely mode of
transmission. This disease's importance resides in the fact that it is transmissible to humans. Due to this
disease's high resistance in the environment researchers who manipulate wild felids should observe strict
prophylactic measures and hygiene to avoid contagion.
Antibodies to dirofilariasis (Dirofilaria immitis) were also encountered (10%). This parasitic blood
disease produced by a nematode has been documented in Panthera onca and P. tigris (Kennedy et al.
1981), F. bangsi costariciensis, H. yagouarundi, F. rufus (Otto 1975), and F. nigriceps (Deem et al.
1998). In domestic cats, dirofilariasis can manifest itself with hyper acute death, asymptomatic disease, or
chronic disease (Dillion 1988, Holmes 1993). In symptomatic infections the cardiopulmonary and
gastrointestinal systems are affected, and dysfunction of the central nervous system is observed (Calvert
1989). The serological prevalence of Dirofilaria in our study was low, which was expected since its
presence is associated with tropical and subtropical climates, which are propitious for the reproduction of
the mosquitoes which are vectors in the transmission cycle (Fiorello 2004).
The death of various individuals monitored in this study was directly related to a marked decrease in
prey species in the study area. Notwithstanding the abundance in previous years of prey species such as
cavies, mice, and ground birds observed during explorations of the park, during the capture phase of field
work in 2003 the scarcity or absence of these species was noticeable. The presence of antibodies to
different infectious agents with absence of clinical symptoms, together with histopathology results
indicative of severe food stress, seem to demonstrate that the documented deaths were not a result of an
epidemic event. However, the poor nutritional state of the animals could have predisposed them to
opportunistic infections, such as the parasitic ones observed, by depression of their immune system. In a
similar manner, the time lapse between capture and the discovery of the dead animals, added to their
apparent normal behavior observed during telemetry monitoring in successive days after capture, preclude
52
capture as a factor in the animal's deaths. Furthermore, histopathology results showed the absence of
lesions indicative of capture myopathy. Finally, health evaluation results, coupled with telemetry
behavioral observations and the posterior reduction in prey abundance, suggest that the deaths were due to
poor body condition and immune depression resulting from prolonged starvation.
Finally, we present evidence of exposure in free-ranging Geoffreys’ cats to various viral and infectious
agents which are common to domestic carnivores. These findings support the need to continue monitoring
the health of wild and domestic populations, in order to understand the role of diseases in population
dynamics, the effects of wild/domestic interactions and their significance for the conservation of wild
felids.
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