Jaguar Populations Research Articles

First record of intestinal parasites in a wild population of jaguar in the Brazilian Atlantic Forest.

Small and isolated wildlife populations may be more susceptible to disease, which makes illness an important issue to investigate regarding the conservation of large carnivores. Here, we present the results of the first investigation of intestinal parasites in one of the last remaining populations of jaguars in the Brazilian Atlantic Forest. We studied parasites from fecal samples using three different techniques for parasitological examination: floatation in saturated sodium chloride solution, sedimentation and formalin-ether centrifugation. Intestinal parasites were detected in 70% of the analyzed samples, and seven taxa (mean = 3.7 taxa/sample) were identified. All the groups of parasites that were identified have been recorded in previous jaguar studies. However, the records of Class Trematoda and nematodes Trichuridae are the first evidence of these groups of worms in free-ranging jaguars in Brazil. Although our results do not provide conclusive evidence on the health of this jaguar population, given its very small size (approximately 20 animals) we stress the need to properly understand the dynamics of disease in this wild population and to evaluate the risk of contracting new diseases from domestic species inhabiting the neighboring areas. These represent imperative actions for the successful conservation of this threatened population of jaguar.

The jaguar's patches: Viability of jaguar populations in fragmented landscapes

Habitat loss and fragmentation have serious consequences for long-term population persistence, thus we investigated the effects of these processes on jaguars (Panthera onca) across the species’ distribution range. We employed theoretical simulations of population dynamics, making use of real and hypothetical landscapes to understand how landscape patterning affects the long-term persistence of species, and investigated the isolated and synergistic effects of habitat loss and fragmentation. Jaguar persistence probability was related both to the amount and pattern of landscape subdivision, but with a strong tolerance for habitat loss because the amount of habitat could be between 230 and 5841km2. In contrast, the persistence probability of smaller jaguar populations decreased dramatically in fragmented landscapes, indicating that fragmentation is a greater threat to jaguar long-term viability than habitat loss. Only two of the 28 populations included in our study were deemed viable in the long-term. Given the increase in habitat fragmentation and the current threat status of the jaguar, we discuss the best strategies for their conservation.

The potential for large-scale wildlife corridors between protected areas in Brazil using the jaguar as a model species

Most large reserves in Brazil do not hold viable populations of jaguars to guarantee the species’ long-term survival. Corridors linking populations have been identified as a potential tool to avoid negative effects of isolation, increasing population viability. Here, we performed a Brazil-wide evaluation of potential large scale corridors connecting protected jaguar populations. Six variables (human population size, dam reservoir size, number of dams, roads, railways and cities) expected to negatively impact jaguar movement were analyzed across 180 potential corridors connecting 298 protected jaguar areas. We established overall disturbance scores for the corridors using a principal components analysis and compared them among the Brazilian biomes. We further investigated which variables separated biomes using a canonical variates analysis. The Atlantic Forest and the semi-arid Caatinga have the most impacted potential corridors, whereas the Amazon and Pantanal still have the best potential corridors. Corridor quality in the Cerrado grasslands was intermediate. All variables but human population size and corridor length contributed significantly to differences in corridor variables among biomes. Our conclusions suggest that we need to plan the implementation of large scale corridors in the Amazon, Pantanal and particularly the Cerrado soon, while potential corridors might still be economically viable. In the much more impacted Atlantic Forest and Caatinga, the need for conservation actions is strongest, but logistical difficulties and costs may turn implementation of corridors unfeasible.

Monitoring jaguar populationsPanthera oncawith non-invasive genetics: a pilot study in Brazilian ecosystems

AbstractThe global population of jaguarsPanthera oncahas decreased significantly since the beginning of the 20th century. Given the scarcity of demographic and biological information, estimating population parameters is critical for the design of conservation measures. The jaguar's elusive behaviour makes it impossible to estimate and monitor populations by direct observation. We propose a non-invasive genetic sampling approach and demonstrate its potential for large-scale monitoring. Sex identification was optimized for faecal samples of jaguars and other felids. We also optimized a set of 11 microsatellite markers for reliable identification of individuals. We estimated the effectiveness of faecal sample genotyping in two distinct Brazilian biomes: the Pantanal and the semi-arid Caatinga. Almost 90% of the samples that were molecularly identified as jaguar (n = 90) were successfully genotyped and were assigned to 30 individuals. Genetic diversity was generally high but was significantly lower in the Caatinga population. We show that non-invasive genetic sampling can be a reliable tool to study population parameters and to monitor the genetic status of jaguar populations in different habitats. It may also be useful for future surveys of jaguars that address ecological, behavioural and conservation issues, and could provide a baseline for non-invasive genetic studies of other wild felid populations.

Occupancy estimation of jaguar Panthera onca to assess the value of east-central Mexico as a jaguar corridor

AbstractThe use of wildlife corridors to maintain landscape connectivity has become increasingly relevant to the conservation of wide-ranging species, including the jaguar Panthera onca. Jaguars are particularly threatened in Mexico, where corridor linkages are tenuous as a result of habitat fragmentation. Our study assessed a section of potential corridor south of the Sierra Madre Oriental in eastern Mexico. We conducted 245 interviews with local inhabitants in 140 36-km2 sampling units over a 5-month period and compiled detection histories for jaguars and five prey species: collared peccary Pecari tajacu, red brocket deer Mazama americana, white-tailed deer Odocoileus virginianus, spotted paca Agouti paca, and nine-banded armadillo Dasypus novemcinctus. These detection histories were then analysed using site occupancy modelling. Each sampling unit was assigned a probability of habitat use based on (1) the two smaller prey species (paca and armadillo) and (2) at least two of the larger prey species (collared peccary and two deer species) using habitat in that unit. This probability estimate was considered a proxy for the prey base of each sampling unit and therefore the unit's suitability as a jaguar corridor. Although the prey base in some areas appears adequate to support a jaguar population, large-scale development projects and the paucity of jaguar sign are major obstacles to this region's potential as a jaguar corridor. Our results suggest that the eastern coast of Mexico may not be a priority area for range-wide jaguar conservation.

Combining camera-trapping and noninvasive genetic data in a spatial capture–recapture framework improves density estimates for the jaguar

Abundance and density are key pieces of information for questions related to ecology and conservation. These quantities, however, are difficult to obtain for rare and elusive species, where even intensive sampling effort can yield sparse data. Here, we combine data from camera-trapping and noninvasive genetic sampling (scat surveys) of a jaguar population in the Caatinga of northeastern Brazil, where the species is threatened and little studied. We analyze data of both survey types separately and jointly in the framework of spatial capture–recapture. Density estimates were 1.45 (±0.46) for the camera-trap data alone, 2.03 (±0.77) for the genetic data alone, and 1.57 (±0.43) and 2.45 (±0.70) for the two methods, respectively, in the joint analysis. Density and other parameters were estimated more precisely in the joint model. Particularly the differences in movement between males and females were estimated much more precisely when combining both data sources, especially compared to the genetic data set alone. When compared to a previous non-spatial capture–recapture approach, present density estimates were more precise, demonstrating the superior statistical performance of spatial over non-spatial capture recapture models. The ability to combine different surveys into a single analysis with shared parameter allows for more precise population estimates, while at the same time enabling researchers to employ complementary survey techniques in the study of little known species.

Selection of habitat by the jaguar, Panthera onca (Carnivora: Felidae), in the upper Paraná River, Brazil

We used data from VHF and GPS radio-tagged jaguars, Panthera onca (Linnaeus, 1758) to quantify jaguar habitat selection and how adult individuals in the Upper Parana River region selected among the available habitat types. We followed the framework in which animals make decisions about resource use at hierarchical stages, namely selection of home range within a study area (second-order selection) and selection of patches within a home range (third-order selection). We quantified habitat preferences at two orders of selection with respect to habitat types and to test the null hypothesis that habitat utilization by jaguars was random at both study sites. Using compositional analysis, we assessed habitat selection by jaguars at second- and third-orders of selection. Jaguars consistently preferred dense marshes and primary forests, and avoided human-dominated areas such as intensively managed open pastures. Although the avoidance of disturbed and developed habitat types by jaguars is not surprising, this is the first study to document it. If small protected areas, such as the ones already existing in the Upper Parana region, are to sustain jaguar populations they, must include and protect as many primary forests and marshlands as possible, so that jaguars can disperse, hunt wild prey and take care of their cubs without being disturbed. What is urgently needed in these jaguar-protected areas is the creation of larger protected areas that can sustain jaguars in their favored habitat.

Critical population status of the jaguar Panthera onca in the Argentine Chaco: camera-trap surveys suggest recent collapse and imminent regional extinction

AbstractThe population of jaguars Panthera onca in the semi-arid Chaco Province is the least well-known in Argentina. Its status in the region is described only from interviews that confirmed its presence until 2003. To update information on the distribution and population density of this species we undertook three camera-trap surveys, combined with searches for sign, at sites across latitudinal and protection gradients, and 156 interviews with local inhabitants across three larger areas. The camera-trap sites were located in areas with the highest density of records in the Argentine Chaco: Copo National Park (1,204 trap days, 24 stations, 344 km of transects), Aborigen Reserve (1,993 trap days, 30 stations, 251 km of transects) and El Cantor (2,129 trap days, 35 stations, 297 km of transects). We did not obtain any photographs of jaguars. We recorded very few jaguar tracks, and only in the Aborigen Reserve (n = 3) and El Cantor (n = 1). The map of distribution points confirmed through interviews suggests that the jaguar range has not changed significantly in the past 10 years; however, the camera-trap and sign surveys suggest that densities are extremely low. Before our study the Chaco population was thought to be the largest in Argentina. This perception was incorrect: the Chaco jaguar population is the most threatened in the country. Systematic, intensive studies are essential to provide the necessary information for decision-making for the management and conservation of threatened species.

SEROSURVEY FOR SELECTED VIRAL INFECTIONS IN FREE-RANGING JAGUARS (PANTHERA ONCA) AND DOMESTIC CARNIVORES IN BRAZILIAN CERRADO, PANTANAL, AND AMAZON

We investigated the exposure of jaguar (Panthera onca) populations and domestic carnivores to selected viral infections in the Cerrado, Amazon, and Pantanal biomes of Brazil. Between February 2000 and January 2010, we collected serum samples from 31 jaguars, 174 dogs (Canis lupus familiaris), and 35 domestic cats (Felis catus). Serologic analyses for antibodies to rabies virus, canine distemper virus (CDV), feline immunodeficiency virus (FIV), and for feline leukemia virus (FeLV) antigen were conducted. The jaguars from Cerrado and Pantantal were exposed to rabies virus, while the jaguars from the Pantanal and the dogs from all three areas were exposed to CDV. Two cats from the Amazonian site were antigen-positive for FeLV, but no jaguars had FeLV antigen or FIV antibody. Canine distemper and rabies viruses should be carefully monitored and considered potential threats to these jaguar populations. Currently FIV and FeLV do not appear to represent a health threat for jaguar populations in this area. Domestic dogs and cats in these areas should be vaccinated, and the movement of domestic animals around protected areas should be restricted.

Understanding species persistence for defining conservation actions: A management landscape for jaguars in the Atlantic Forest

Habitat models constitute useful instruments for understanding species-habitat interactions and can constitute helpful conservation tools. The Upper Paraná Atlantic Forest (UPAF) of South America still holds the world’s southernmost jaguar (Panthera onca) population. Our aims were: (i) to test several a priori hypotheses on the factors affecting jaguar persistence in this region, (ii) to map habitat suitability and identify areas with potentially conflicting habitat conditions, and (iii) to identify priority areas for management and improve the conservation initiatives for jaguars and the UPAF. Following an information-theoretic approach, we used presence records of jaguars and pseudo-absences in generalized linear models. We structured hypotheses into two groups which demand different management actions: land cover and human persecution. The best model of each group was used to develop a two-dimensional habitat model. Jaguar persistence was favoured by current and historical native forest cover, and hindered by human land uses. Protection favoured jaguar presence whereas human accessibility and high human population density had negative effects. The two-dimensional model suggests that <8% (20,670km2) of the landscape represents potential core areas for jaguars (good land-cover characteristics and low human persecution) and 11.8% (32,563km2) stands as potentially attractive sinks where good land-cover conditions conflict with high human persecution. Reduction of human persecution is urgently needed to increase the core areas for jaguars in this region, but improvement of land-cover conditions is important for sustaining the connectivity among jaguar populations that seem to be isolated in different areas of the UPAF.

Primer registro del murciélago bigotón &lt;i&gt;Pteronotus parnelli&lt;/i&gt; (Chiroptera: Mormoopidae) al Este de Sonora

AbstractParnell’s mustached bat, Pteronotus parnellii, is found from southern Sonora and Tamaulipas to Chiapas in Mexico. On October 3, 2012, at 18:30 hr, six and nine-meter nets were placed above water ponds in the Babisal creek located in the “Northern Jaguar Reserve” near the town of Sahuaripa. At 19:50 hrs the six-meter net was checked, and an adult male, without scrotum, of the species Pteronotus parnellii was found at a height of 70cm above ground level. The Sahuaripa region in east-central Sonora, is outside the known distribution range of this species extending it by at least 220 km north of the Sierra de Alamos. The “Northern Jaguar Reserve” where Pteronotus parnellii was found, is a protected area and an important wilderness area for the protection of the northernmost breeding population of jaguars. Key words: Pteronotus parnellii, Reserva Jaguar del Norte, Sonora, october. Palabras clave: Pteronotus parnellii, Reserva Jaguar del Norte, Sonora, octubre.

High Proportion of Male Faeces in Jaguar Populations

Faeces provide relevant biological information which includes, with the application of genetic techniques, the sex and identity of individuals that defecated, thus providing potentially useful data on the behaviour and ecology of individuals, as well as the dynamics and structure of populations. This paper presents estimates of the sex ratio of different felid species (jaguar, Panthera onca; puma, Puma concolor; and ocelot/margay, Leopardus pardalis/Leopardus wiedi) as observed in field collected faeces, and proposes several hypotheses that could explain the strikingly high proportion of faeces from male jaguars. The proportion of male and female faeces was estimated using a non-invasive faecal sampling method in 14 study areas in Mexico and Brazil. Faecal samples were genetically analysed to identify the species, the sex and the individual (the latter only for samples identified as belonging to jaguars). Considering the three species, 72.6% of faeces (n = 493) were from males; however, there were significant differences among them, with the proportion from males being higher for jaguars than for pumas and ocelots/margays. A male-bias was consistently observed in all study areas for jaguar faeces, but not for the other species. For jaguars the trend was the same when considering the number of individuals identified (n = 68), with an average of 4.2±0.56 faeces per male and 2.0±0.36 per female. The observed faecal marking patterns might be related to the behaviour of female jaguars directed toward protecting litters from males, and in both male and female pumas, to prevent interspecific aggressions from male jaguars. The hypothesis that there are effectively more males than females in jaguar populations cannot be discarded, which could be due to the fact that females are territorial and males are not, or a tendency for males to disperse into suboptimal areas for the species.

Comparison of density estimation methods for mammal populations with camera traps in the Kaa‐Iya del Gran Chaco landscape

AbstractSampling animal populations with camera traps has become increasingly popular over the past two decades, particularly for species that are cryptic, elusive, exist at low densities or range over large areas. The results have been widely used to estimate population size and density. We analyzed data from 13 camera trap surveys conducted at five sites across the Kaa‐Iya landscape, Bolivian Chaco, for jaguar, puma, ocelot and lowland tapir. We compared two spatially explicit capture–recapture (SCR) software packages: secr, a likelihood‐based approach, and SPACECAP, a Bayesian approach, both of which are implemented within the R environment and can be used to estimate animal density from photographic records of individual animals that simultaneously employ spatial information about the capture location relative to the sample location. As a non‐spatial analysis, we used the program CAPTURE 2 to estimate abundance from the capture–recapture records of individuals identified through camera trap photos combined with an ad hoc estimation of the effective survey area to estimate density. SCR methods estimated jaguar population densities from 0.31 to 1.82 individuals per 100 km2 across the Kaa‐Iya sites; puma from 0.36 to 7.99; ocelot from 1.67 to 51.7; and tapir from 7.38 to 42.9. Density estimates using either secr or SPACECAP were generally lower than the estimates generated using the non‐spatial method for all surveys and species; and density estimates using SPACECAP were generally lower than that using secr. We recommend using either secr or SPACECAP because the spatially explicit methods are not biased by an informal estimation of an effective survey area. Although SPACECAP and secr are less sensitive than non‐spatial methods to the size of the grid used for sampling, we recommend grid sizes several times larger than the average home range (known or estimated) of the target species.

Population status of jaguars (Panthera onca) and pumas (Puma concolor) in northeastern Sonora, Mexico

Jaguars are endangered in Mexico and the United States, necessitating careful monitoring of population status. We determined minimum numbers of jaguars and sympatric pumas in a small population in northern Sonora, Mexico, the nearest known breeding population to the United States, by photographic captures supplemented by idiosyncratic features of tracks from track surveys (1999-2005). We also developed a discriminant function to differentiate species (jaguar v. puma) and sexes within species, which also aided in individual identification. Photographic captures identified 5 individual jaguars; this estimate was increased to 12 using idiosyncratic features and discriminant analysis of tracks.Jaguar kittens were only detected by track surveys. All jaguars identified by photographs were previously detected by tracks, but most (7 of 12) known from tracks were not captured in photographs. Jaguar presence was fluid; we identified 6 individual jaguars from 1999-2003, but only 3 of these were still present in 2004. We documented 4 new individuals during 2005, when none of the previously identified jaguars were detected. Similarly, we identified 14 individual pumas by tracks, but only 11 of these were captured in photographs. Four hindfoot measurements varied among species and sexes of jaguars and pumas, and these measurements were able to correctly classify 85-97% of tracks to the correct species and sex. Due to the high turnover of this jaguar population, which is at its fringe of the jaguar range in North America, we recommend constant monitoring of population status with camera traps and track surveys. If only limited resources are available, we recommend monitoring only with track surveys because they detected a greater number of individuals and all age classes of individuals.

Can species distribution modelling provide estimates of population densities? A case study with jaguars in the Neotropics

AbstractAim To test the prediction that environmental suitability derived from species distribution modelling (SDM) could be a surrogate for jaguar local population density estimates.Location Americas.Methods We used 1409 occurrence records of jaguars to model the distribution of the species using 11 SDM methods. We tested whether models’ suitability is linearly correlated with jaguar population densities estimated from 37 different locations. We evaluated whether the relationship between density and suitability forms a constraint envelope, in which higher densities are found mainly in regions with high suitability, whereas low densities can occur in regions with variable suitability. We tested this using heteroscedasticity test and quantile regressions.Results A positive linear relationship between suitability and jaguar density was found only for four methods [bioclimatic envelope (BIOCLIM), genetic algorithm for rule set production (GARP), maximum entropy (Maxent) and generalized boosting models (GBM)], but with weak explanatory power. BIOCLIM showed the strongest relationship. Variance of suitability for lower densities values was larger than for higher values for many of the SDM models used, but the quantile regression was significantly positive only for BIOCLIM and random forests (RF). RF and GBM provided the most accurate models when measured with the standard SDM evaluation metrics, but possess poor relationship with local density estimates.Main conclusions Results indicate that the relationship between density and suitability could be better described as a triangular constraint envelope than by a straight positive relationship, and some of the SDM methods tested here were able to discriminate regions with high or low local population densities. Low jaguar densities can occur in areas with low or high suitability, whereas high values are restricted to areas where the suitability is greater. In high suitability areas but with low jaguar density estimates, we discuss how extrinsic factors driving abundance could act at local scales and then prevent higher densities that would be expected by the favourable regional environmental conditions.

JaguarsPanthera oncain the Greater Lacandona Ecosystem, Chiapas, Mexico: population estimates and future prospects

AbstractJaguarPanthera oncapopulations have declined severely in Mexico because of habitat loss and poaching of the species and its natural prey. One of the most important, but poorly known, populations of the jaguar remaining in Mexico resides in the Greater Lacandona Ecosystem in Chiapas. Our objective was to determine the density of jaguars in southern Montes Azules Biosphere Reserve and to estimate population size inside the Natural Protected Areas of this Ecosystem. Jaguar densities were estimated during the dry and rainy seasons of 2007 and the dry season of 2008 using camera-trapping combined with closed capture-recapture models. The lowest density estimate was recorded during the 2007 dry season (1.7 ± SE 0.7 per 100 km2) and the highest during the 2008 rainy season (4.6 ± SE 1.6 per 100 km2). Estimating the extent of potential jaguar habitat in the Natural Protected Areas and extrapolating density estimates to these reserves indicates that they could support 62–168 jaguars. This result highlights the potential importance of this Ecosystem for the conservation of the jaguar in the Mayan Forest and Mexico. The implementation of measures to secure the long-term conservation of this population and jaguar population connectivity in the Mayan Forest is urgently required.

Tungiasis in a free-ranging jaguar (Panthera onca) population in Brazil

Tungiasis is an ectoparasitic disease caused by fleas of the genus Tunga. The disease is reported to occur mostly in human populations. In wildlife, however, the occurrence and impact of this disease remains uncertain. We captured and examined 12 free-ranging jaguars for the presence of Tunga penetrans in the Pantanal region of Mato Grosso do Sul state, Brazil. Tungiasis prevalence was 100% in the population; lesions were confined to the jaguar's paws. T. penetrans was identified based on the characteristics of the embedded fleas and the morphological identification of a collected free-living flea. The intensity and stage of infestation varied between individual animals. However, in general, all captured jaguars were in good health. The 100% prevalence of tungiasis may be related to the fact that all captures were performed during the dry season. Their high ecological requirements for space make jaguars potential disseminators of T. penetrans in the Pantanal region. Because cattle ranching and ecotourism are the main economic activities in the Pantanal, further studies should evaluate the risks of tungiasis to human and animal health. To the best of our knowledge, this is the first report of tungiasis in jaguars.

Using occupancy models to investigate space partitioning between two sympatric large predators, the jaguar and puma in central Brazil

Coexistence of sympatric species is mediated by resource partitioning. Pumas occur sympatrically with jaguars throughout most of the jaguar's range but few studies have investigated space partitioning between both species. Here, camera trapping and occupancy models accounting for imperfect detection were employed in a Bayesian framework to investigate space partitioning between the jaguar and puma in Emas National Park (ENP), central Brazil. Jaguars were estimated to occupy 54.1% and pumas 39.3% of the sample sites. Jaguar occupancy was negatively correlated with distance to water and positively correlated with the amount of dense habitat surrounding the camera trap. Puma occupancy only showed a weak negative correlation with distance to water and with jaguar presence. Both species were less often present at the same site than expected under independent distributions. Jaguars had a significantly higher detection probability at cameras on roads than at off-road locations. For pumas, detection was similar on and off-road. Results indicate that both differences in habitat use and active avoidance shape space partitioning between jaguars and pumas in ENP. Considering its size, the jaguar is likely the competitively dominant of the two species. Owing to its habitat preferences, suitable jaguar habitat outside the park is probably sparse. Consequently, the jaguar population is likely largely confined to the park, while the puma population is known to extend into ENP's surroundings.

Estimating jaguar population density using camera‐traps: a comparison with radio‐telemetry estimates

Reliable data on jaguar population densities are needed to propose appropriate conservation and management strategies, and camera trapping may be effective for estimating the population density of secretive large cats. I determined the population density of jaguars in the Chamela-Cuixmala Biosphere Reserve along the coast of Jalisco, Mexico, through camera trapping and capture–recapture analysis during the dry season of March to June 2008. I applied the half mean maximum distance moved (1/2MMDM) to calculate the radius of the effectively sampled area, and compared this with estimates of the effectively sampled area based on existing data on mean home range of jaguars at the study site. I found that both methods of calculating the effectively sampled area produced similar population density estimates. The widely used 1/2MMDM based on camera-trapping data produced a population density of 5.3 jaguars/100 km2, while calculation of the effectively sampled area based on mean home range produced a population density of 5 jaguars/100 km2. Despite the small size of the 131-km2 Chamela-Cuixmala Biosphere Reserve, jaguar population density was relatively high, suggesting that small, well-protected reserves can be important refuges for jaguars.

Cannibalism Among Jaguars (Panthera onca)

Abstract This is the first report of cannibalism in a free-ranging population of jaguars (Panthera onca). An encounter among unfamiliar jaguars may have provoked social stress, a behavior reported in other free-ranging carnivores.