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1.
Rev. biol. trop ; 62(4): 1449-1458, oct.-dic. 2014. ilus, mapas, tab
Article in English | LILACS | ID: lil-753702

ABSTRACT

Habitat characteristics and human activities are known to play a major role in the occupancy of jaguars Panthera onca across their range, however the key variables influencing jaguar distribution in Tortuguero National Park, Costa Rica, have yet to be identified. This study evaluated jaguar occupancy in Tortuguero National Park and the surrounding area. Jaguar detection/non-detection data was collected using digital camera traps distributed within the boundaries of the protected area. Local community members were also interviewed to determine jaguar occurrence in the Park’s buffer zone. Occupancy models were then applied to identify the habitat characteristics that may better explain jaguar distribution across the study area. From June 2012 to June 2013, a total of 4 339 camera trap days were used to identify 18 individual jaguars inside the protected area; 17 of these jaguars were exclusively detected within the coastal habitat, whilst the remaining individual was detected solely within the interior of the Park. Interviewees reported 61 occasions of jaguar presence inside the buffer zone, between 1995 and 2013, with 80% of these described by the communities of Lomas de Sierpe, Barra de Parismina and La Aurora. These communities also reported the highest levels of livestock predation by jaguars (85% of attacks). In the study area, jaguar occurrence was positively correlated with the seasonal presence of nesting green turtles Chelonia mydas, and negatively correlated with distance to the Park boundary. Our findings suggested that the current occupancy of the jaguar in the study area may be a response to: 1) the vast availability of prey (marine turtles) on Tortuguero beach, 2) the decline of its primary prey species as a result of illegal hunting inside the Park, and 3) the increase in anthropogenic pressures in the Park boundaries. Rev. Biol. Trop. 62 (4): 1449-1458. Epub 2014 December 01.


Las características del hábitat y las actividades humanas juegan un papel importante en la presencia del jaguar Panthera onca en toda su área de distribución, sin embargo, las variables clave que influyen en la distribución del jaguar en el Parque Nacional Tortuguero, Costa Rica, aún no se han identificado. Por lo tanto se evaluó la presencia del jaguar Panthera onca en este parque nacional y su área de amortiguamiento. Se recolectaron datos de detección/no detección del jaguar mediante cámaras trampa ubicadas dentro del parque, y se realizaron encuestas en las comunidades del área de amortiguamiento. Posteriormente, se emplearon modelos de ocupación para identificar los atributos del hábitat que mejor explicaban la presencia del felino en el área. Se identificaron 18 jaguares dentro del parque, de los cuales 17 estuvieron exclusivamente en el hábitat costero. En el área de amortiguamiento, las comunidades con una mayor presencia del felino (Lomas de Sierpe, Barra de Parismina y La Aurora) coincidieron con las zonas más conflictivas, en relación a la cacería y la depredación de jaguar sobre el ganado. La probabilidad de ocupación del jaguar se incrementa a medida que aumenta la presencia de la tortuga verde Chelonia mydas, y disminuye conforme la distancia al límite del parque se incrementa. Nuestros resultados indican que la actual presencia del jaguar se debe a: 1) la alta disponibilidad de presas (tortugas marinas) en el hábitat costero, 2) la disminución de las principales especies presa como resultado de la cacería y 3) al incremento de las actividades humanas en el área de amortiguamiento del parque.


Subject(s)
Animals , Female , Male , Conservation of Natural Resources , Ecosystem , Panthera/classification , Costa Rica , Population Density , Population Dynamics , Panthera/physiology , Seasons
2.
Rev. biol. trop ; 62(2): 689-698, Jun.-Aug. 2014. ilus, tab
Article in English | LILACS | ID: lil-715463

ABSTRACT

Jaguars (Panthera onca) are the largest predator in lowland forests of Amazonia but there have been few studies on their occurrence and activity in such forests. Here, we used camera traps to document the occurrence and activity of jaguars within a local area (~650ha) of lowland forest of Eastern Ecuador, over two sample periods (2005-2008, 7 222 trap days; 2010-2012, 6 199 trap days). We accumulated 151 independent photos of jaguars (189 total photographs) that represented 21 different individuals, including 11 males (114 photographs), seven females (32 photographs), and three that could not be assigned to a sex. Individual jaguars varied in the number of months they were recorded in the area; ten were photographed in only one month; five were photographed over periods of 8 to 22 months; and five from 45 to 81 months. Capture rates across all camera stations averaged 10.6/1 000 trap days; capture rates did not differ between the two sample periods. Male jaguars were more active during the day (06:00am-18:00pm; 71% of photographs), whereas females were equally active during the day and night. Monthly activity was variable but showed no consistent pattern. Although the study area is much smaller than typical home ranges of jaguars, the area is clearly visited by a large number of different individuals, some of whom repeatedly visit the area, indicating that it forms part of their home range. Other individuals likely were simply passing through the area. Based on the number of jaguars recorded during this study, it is clear that the region is an important area for conservation. Continued protection will be needed to ensure that populations of jaguars and other species remain viable. Rev. Biol. Trop. 62 (2): 689-698. Epub 2014 June 01.


El jaguar (Panthera onca) es el depredador más grande de los bosques bajos de la Amazonía, pero existen pocos estudios sobre su presencia y actividad en los mismos. En este estudio utilizamos cámaras trampa para documentar la presencia y actividad de jaguares dentro de una área de bosque bajo de la Amazonía este de Ecuador (~650 ha) en dos períodos (2005-2008, 7 222 trampas noche; 2010-2012, 6 199 trampas noche). Acumulamos 151 fotos independientes de jaguares (189 fotografías en total) que representaron 21 individuos, incluyendo 11 machos (114 fotos), siete hembras (32 fotos) y tres a los que no se les pudo asignar sexo. Los jaguares individuales variaron en el número de meses en que fueron registrados en el área; diez fueron fotografiados solo en un mes; cinco fueron fotografiados en un periodo entre 8 y 22 meses; y cinco jaguares entre 45 y 81. Las tasas de captura a través de las estaciones de trampeo promediaron 10.6/1 000 trampas noche; las tasas de captura no presentaron diferencias en los dos períodos de muestreo. Los jaguares machos fueron más activos durante el día (06:00am-18:00pm; 71% de las fotografías) mientras que las hembras fueron igualmente activas tanto en el día como en la noche. La actividad mensual fue variable pero no mostró un patrón consistente. Aunque el área de estudio es mucho más pequeña que el rango de vida típico para un jaguar, el área es claramente visitada por un alto número de individuos diferentes, algunos de los cuales visitan repetidamente el lugar, indicando que este forma parte de su rango de vida. Es probable que otros individuos solamente sean transeúntes del área.


Subject(s)
Animals , Female , Male , Behavior, Animal/physiology , Panthera/physiology , Ecuador , Photography , Population Density , Panthera/classification , Trees
3.
Rev. biol. trop ; 56(4): 1893-1904, Dec. 2008. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-637786

ABSTRACT

Identification of individual jaguars (Panthera onca) and pumas (Puma concolor) based on footprint morphometry (Carnivora: Felidae). Estimating feline abundance becomes particularly difficult, sometimes impossible, due to their elusive behavior and extensive space requirements. Available techniques are expensive and/or poorly efficient, therefore alternative methods are needed. The objective of this study was to assess the possibility of identifying individual jaguars and pumas based on morphometric analyses of their tracks. The footprints of five jaguars and four pumas were drawn and the foot (hind or fore foot, left or right foot) and the substrate were recorded. We took 16 measures from each footprint including lengths, widths, areas and angles. Variables were analyzed by using Principal Component Analysis (PCA) and substituted by the first Principal Component (PC) (> 70 % variance). We assessed the effect of the substrate and type of foot by means of paired t-student tests, and found differences between fore and hind feet and footprints from the same individual when made on soil or sand. No differences were found between right or left feet. The footprints changed over time as revealed by Multiple ANOVA. Different individuals could be identifyied based on discriminant analyses with more than 70 % confidence. We conclude that this method is feasible and can be useful when studying endangered felines. Rev. Biol. Trop. 56 (4): 1893-1904. Epub 2008 December 12.


Estimar la abundancia de felinos resulta particular-mente difícil o, incluso imposible, debido a su comportamiento críptico y sus amplios requerimiento espaciales. Las técnicas disponibles para estimar abundancia son costosas y poco eficientes, por lo que es necesario proponer métodos alternativos. El objetivo de este trabajo fue evaluar la capacidad de identificación de individuos utilizando el análisis morfométrico de huellas en yaguares y pumas. Para ello, se dibujaron huellas de cinco yaguares y cuatro pumas, registrándose el tipo de pata que dio origen a la huella y el sustrato. Para cada huella se tomaron 16 mediciones morfológicas de ángulos, largos, anchos y áreas. Las variables de largos, anchos y áreas fueron analizadas con un Análisis de Componentes Principales (ACP) y sustituidas por el primer componente principal (más del 70 % de la varianza en todos los casos). Se evaluó el efecto del sustrato y del tipo de pata a partir de pruebas t-pareadas, encontrándose diferencias entre huellas del mismo individuo dibujadas a partir de arena o tierra (t-pareadas p < 0.05), así como diferencias en todas las variables para patas delanteras y traseras (t-pareadas p < 0.05 en todos los casos). No se encontraron diferencias entre patas izquierdas o derechas. El efecto de la edad de la huella se estudió con Análisis Múltiples de Varianza, en los que se revelaron diferencias en las variables con respecto a la edad de la huella. Se realizaron análisis discriminantes por especies, sustrato de la huella y tipo de pata, para determinar la capacidad del método de discriminar entre individuos. Se obtuvo una adecuada separación de los individuos con más del 70 % de confianza. Se concluye que este método es factible y puede ser de gran utilidad especialmente en el caso de felinos amenazados.


Subject(s)
Animals , Female , Male , Forelimb/anatomy & histology , Hindlimb/anatomy & histology , Panthera/classification , Puma/classification , Population Density , Panthera/anatomy & histology , Puma/anatomy & histology , Reproducibility of Results , Venezuela
4.
Biota neotrop. (Online, Ed. port.) ; 7(1)2007. ilus, mapas, tab
Article in Portuguese | LILACS | ID: lil-459161

ABSTRACT

A predação de rebanhos domésticos por onças-pintadas (Panthera onca) e onças-pardas (Puma concolor) foi quantificada de 1998 a 2000 e a opinião local para resolver o conflito foi investigada em duas comunidades quilombolas na Mata Atlântica. Os responsáveis pelas propriedades foram entrevistados regularmente de maio de 2000 a janeiro de 2001. A predação foi dependente do número de animais domésticos nas propriedades, foi aparentemente seletiva e possivelmente sazonal. O prejuízo econômico foi alto quando associado com o baixo número de criações. A população expressou uma visão bastante negativa frente à presença de onças e a maior parte (54 por cento) sugeriu o extermínio desses animais. Conhecer a percepção local é fundamental para adotar um planejamento participativo que reduza as perdas dos proprietários e garanta a conservação dos grandes felinos.


Domestic livestock predation by jaguars (Panthera onca) and pumas (Puma concolor) was recorded from 1998 to 2000 and local opinion to solve the conflict was investigated in two quilombola communities in the Atlantic Forest. The householders were interviewed regularly from May 2000 to January 2001. Predation depended on the number of domestic animals per household, and was apparently selective and possibly seasonal. The economic damage was high when associated with the low livestock number. People's attitude towards predators was negative and most of those surveyed (54 percent) suggested these animals should be eliminated. Knowing the local perception is essential to adopt a participative management to reduce household losses and to guarantee large cats' conservation.


Subject(s)
Animals, Domestic/injuries , Hunting/analysis , Hunting/adverse effects , Panthera/classification , Panthera/growth & development , Puma/classification , Puma/growth & development
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