Jaguar Research Articles

Present but not detected: new records increase the jaguar's area of occupancy in the coastal Atlantic Forest

AbstractThe jaguar Panthera onca has lost 85% of its habitat in the Atlantic Forest, where it persists in small and isolated populations in the largest fragments. In the absence of recent records, the jaguar had previously been presumed extinct in the large Atlantic Forest fragments of the Serra do Mar in southern Brazil. However, as this region is mountainous, densely forested and difficult to access, the jaguar could still be present, but undetected. We carried out an intensive survey using camera traps and interviews with local people in a large (c. 6,500 km2) forest block. During 2011–2019, 98 camera-trap stations were established (14,239 trap-days), and 249 interviews were conducted in 102 grid cells of 5 × 5 km. We obtained the first images of the jaguar in the region, from which five individuals were identified, and interviewees provided records of the jaguar in 24 grid cells. Our findings increase the range of this species in the Atlantic Forest by 9%, and we recommend that the area should be classified as a jaguar conservation unit. As the area we surveyed is adjacent to the Serra do Mar jaguar conservation unit, the combined area of 19,262 km2 is the largest priority area for jaguar conservation in the Atlantic Forest. This proposed jaguar conservation unit could serve as a vital source of jaguar individuals for the coastal forests further south. We recommend that surveys are extended southwards to Santa Catarina state to determine whether the presumed extinction of jaguars in this state is another case of a false absence.

Disappearance of an ecosystem engineer, the white-lipped peccary (Tayassu pecari), leads to density compensation and ecological release

Given the rate of biodiversity loss, there is an urgent need to understand community-level responses to extirpation events, with two prevailing hypotheses. On one hand, the loss of an apex predator leads to an increase in primary prey species, triggering a trophic cascade of other changes within the community, while density compensation and ecological release can occur because of reduced competition for resources and absence of direct aggression. White-lipped peccary (Tayassu pecari—WLP), a species that typically co-occurs with collared peccary (Pecari tajacu), undergo major population crashes—often taking 20 to 30-years for populations to recover. Using a temporally replicated camera trapping dataset, in both a pre- and post- WLP crash, we explore how WLP disappearance alters the structure of a Neotropical vertebrate community with findings indicative of density compensation. White-lipped peccary were the most frequently detected terrestrial mammal in the 2006–2007 pre-population crash period but were undetected during the 2019 post-crash survey. Panthera onca (jaguar) camera trap encounter rates declined by 63% following the WLP crash, while collared peccary, puma (Puma concolor), red-brocket deer (Mazama americana) and short-eared dog (Atelocynus microtis) all displayed greater encounter rates (490%, 150%, 280%, and 500% respectively), and increased in rank-abundance. Absence of WLP was correlated with ecological release changes in habitat-use for six species, with the greatest increase in use in the preferred floodplain habitat of the WLP. Surprisingly, community-weighted mean trait distributions (body size, feeding guild and nocturnality) did not change, suggesting functional redundancy in diverse tropical mammal assemblages.

The jaguar’s flybox

The jaguar’s flybox

Community‐based monitoring of wild felid hunting in Central Amazonia

AbstractHunting is a critical issue in wild felid conservation, contributing to the decline of these species worldwide. Here, we present 18 years of a community‐based monitoring program, quantifying and characterizing wild felid hunting in two sustainable development reserves in Central Amazonia. We investigated how felid hunting was affected by the flood pulse and whether local human population size, habitat type, and total hunting events influenced felid hunting. We recorded 71 adult felids being killed, most of them in opportunistic events (88.7%), usually during hunting expeditions aimed at other game species. Four felid species were recorded in the hunts (Panthera onca, Leopardus pardalis, Puma concolor, and Leopardus wiedii) with jaguars accounting for almost half of all hunting events (N = 35). We found that more felid hunting events occurred during the flooded season, in more populated communities, and in várzea habitats. Most felids were hunted opportunistically, demonstrating the complexity of human‐felid interactions. Stories of attacks on humans are widespread in the study area, which may strengthen an instinctive fear of felids, driving their persecution. The increase of hunting events during the flooded season seems to be related to a higher probability of encounters between humans and wild felids. High waters make fishing difficult, therefore, locals hunt more, entering deep into the forest through flooded habitats. Since jaguars have an arboreal lifestyle during the flooded season in várzea forests, they are easily spotted by locals and have less of a chance to escape since they are slower and more exposed when swimming, which increases the probability of being killed. It is generally acknowledged that involving local stakeholders in conservation projects is essential for their success. In our case, collaboration among researchers and community members was fundamental to access hunting information. We show that community‐based monitoring empowers the local communities and facilitates data collection on sensitive topics.

The effect of environment on intestinal microbial diversity of Panthera animals may exceed genetic relationship.

Intestinal microbes are important symbiotes in the gastrointestinal tract of mammals, which are affected by food, environment, climate, genetics, and other factors. The gut microbiota of felines has been partially studied, but a comprehensive comparison of the gut microbiota of Panthera species was less reported. In this study, we compared the gut microbial composition and diversity of five species of Panthera (Panthera tigris, Panthera leo, Panthera onca, Panthera pardus, and Panthera uncia) by 16S ribosomal RNA (rRNA) amplicon sequencing. The results showed that Firmicutes was the most abundant phylum among all the Panthera species, followed by Actinobacteria, Fusobacteria, Bacteroidetes, Proteobacteria, Acidobacteria, Verrucomicrobia, Gemmatimonadetes, and Euryarchaeota. There were significant differences in observed species of fecal microbiota among different Panthera animals (P < 0.05), indicating that there is species specificity among Panthera fecal microbiota. When the samples were further grouped according to sampling locations, the comparison of the alpha diversity index between groups and beta diversity analysis showed that there were significant differences in the fecal microflora of animals from different sampling locations. Cluster analysis showed that fecal microbes of animals from the same sampling location were clustered, while gut microbes of animals of the same species, but from different sampling locations, were separated. These results indicate that environment may have more influence on mammals’ fecal microbial diversity than genetic relationships.

New queen? Evidence of a long-living Jaguar Panthera onca (Mammalia: Carnivora: Felidae) in Tikal National Park, Guatemala

Despite the abundant literature on the Jaguar Panthera onca, several aspects of its natural history and ecology such as longevity and residency of wild individuals are still little studied and poorly known. We conducted a camera trapping study in Tikal National Park, Guatemala, during the dry season and early rainy season from April to July 2018. We compared our results with results of previous studies and thereby came across a presumably female adult individual that was recorded in 2009 and again during our survey. We therefore assume that this virtual female is a potential long-term resident Jaguar in this core zone of the Selva Maya, one of the largest and well-conserved forests in the Neotropics and a priority area for the conservation of this species. We recommend implementing systematic and long-termed studies in Guatemala as a tool for the evaluation and management of the species, and to monitor the effectiveness of protected and priority areas in order to ensure the conservation of the Jaguar.

Osteophagia of sea turtle bones by white-tailed deer (Odocoileus virginianus) in Santa Rosa National Park, northwestern Costa Rica

Herbivores obtain nutrients mostly from the vegetation they consume, but may obtain additional minerals during periods of nutritional stress by consuming bones (osteophagia), a behavioral strategy that has been reported for many wild ungulate species, including the white-tailed deer (Odocoileus virginianus). Here we document multiple records (n = 183 camera-trap records) of osteophagia by white-tailed deer chewing sea turtle remains (resulting from jaguar [Panthera onca] predation) near a nesting beach in Santa Rosa National Park, Costa Rica during January-September 2017. Females with fawns, males with hard and velvet-covered antlers, and non-spotted fawns reached a peak of sea turtle bone consumption during June to August. We hypothesize that seasonality, sex, age, and individual growth stage influence the frequency of osteophagy as a strategy to cope with environmental changes and food resource scarcity. Finally, these observations highlight the role of an apex predator as indirectly influencing rare but important ecological processes.

Large Felid and Peccary Habitat Use in Isolated and Contiguous Forest in Panamá: Implications for Conservation

Background and Research Aims Wildlife research in Panamá has focused primarily on protected areas along the Central Cordillera, where much of the remaining mature rainforest habitat is located. Information on large felid and prey habitat use in isolated habitats in Panamá is therefore limited. Here, we estimated occupancy and detection probabilities, as affected by habitat and anthropogenic influences, for 2 felid species (jaguars [ Panthera onca] and pumas [ Puma concolor]), and 2 prey species (white-lipped peccaries [ Tayassu pecari] and collared peccaries [ Pecari tajacu]). Methods Camera trap surveys were conducted during 2014–2015 at Cerro Hoya National Park (CHNP), an isolated remnant of tropical rainforest habitat, and Darién National Park (DNP), a large tract of continuous rainforest habitat. We used single-season, single-species occupancy modeling to estimate probabilities of detection and habitat use of our focal species. Results Three of the 4 focal species were detected at both sites, excluding white-lipped peccary at CHNP. Detection of jaguars and white-lipped peccaries at DNP was highest in February, while detection of collared peccaries at DNP and pumas at CHNP was highest in May and April, respectively. Peccary habitat use was uniform across sites and unaffected by habitat covariates. Both felids preferred habitat further away from anthropogenic disturbance, and jaguars preferred habitat at higher elevations than pumas. Conclusion We further confirm the presence of jaguars and likely local extirpation of white-lipped peccaries in CHNP. Temporal variations influenced detections of focal species. Habitat use of felids was negatively affected by anthropogenic disturbance and elevation. Implications for Conservation Habitat fragmentation and human activities negatively influenced habitat use of felids at both study areas. Given that CHNP serves as one of the last remnants of forest habitat outside the Central Cordillera, we recommend that CHNP be considered a top priority area for wildlife conservation in Panamá.

Overlooked jaguar guardians: Indigenous territories and range-wide conservation of a cultural icon.

Indigenous territories (ITs) are an integral component of global conservation strategies. We evaluate the range-wide overlap of ITs and the distribution of the jaguar (Panthera onca), a Neotropical apex predator with considerable cultural significance among Indigenous Peoples. We quantified overlap between protected areas (PAs) and ITs among: (1) jaguar range, (2) the species' core habitats, known as Jaguar Conservation Units (JCUs), and (3) corridors connecting JCUs. We further evaluated deforestation rates between 2000 and 2020 among protected, unprotected, and indigenous portions of JCUs and corridors and compared jaguar density estimates among these land tenures. Our results indicate that ITs overlap 27.7% of jaguar range. South American JCUs and corridors, which comprise ~ 94% of jaguar distribution, experienced significantly less deforestation where ITs intersected PAs. We documented an unbalanced ratio of jaguar density estimates between indigenous and non-indigenous areas, highlighting the need for more representative sampling. Collaborative approaches for jaguar conservation, informed and guided by indigenous knowledge, can support more inclusive and effective monitoring that reduces dependence on external support.

Capybara responses to varying levels of predation risk

Predators can generate physiological and behavioural responses in prey individuals. Thus, carnivore reintroductions might cause profound changes in communities and ecosystems by modifying antipredator responses. Combining observational and experimental approaches, we compared the short- and long-term antipredator responses of capybaras, Hydrochoerus hydrochaeris , between a landscape with a high density of predators (Pantanal, Brazil) and a landscape where predators became extinct in the mid-20th century but where a jaguar reintroduction project was in progress (Iberá, Argentina). Generalized linear models were used to test whether the presence of natural predators affects capybara behavioural budgets, gregarious behaviour and the associated physiological stress responses and to test whether, in the short term, capybaras increase their vigilance levels after detecting the proximity of a simulated predator (a playback of jaguar, Panthera onca , calls). Capybaras in the Pantanal did not show higher levels of vigilance but they spent a greater proportion of time foraging than did capybaras in Iberá. Pantanal groups were smaller and foraged closer to water. The baseline levels of stress hormones tended to be higher in Iberá. In response to simulated stimuli, both populations responded to predator sound cues by increasing vigilance, but Iberá groups also increased vigilance in response to a control sound, suggesting that they did not recognize the predator stimulus as a greater risk than another stimulus. In areas with predators, capybaras may reduce predation risk by choosing safer areas, where they can spend more time foraging when predators are not nearby. Vigilance may be only a reactive response to cues of the predator's proximity. Understanding the capybara's antipredator responses may help predict the potential effects and the success of jaguar reintroduction in a region where the jaguar has been absent for over 80 years. • Capybaras facing regular jaguar predation spent more time foraging in safe zones. • Capybaras living without predators did not recognize predator sound stimuli. • Vigilance may be only a reactive response to cues of the predator's proximity. • Prey released from predation for generations may lose some antipredator behaviours. • Naïvety and high density of capybaras could predict successful jaguar reintroduction.

Use of cenotes and the cave environment by mammals on the Yucatán Peninsula, Mexico

AbstractMammals are important sources of nutrients to cave ecosystems, and in some circumstances, caves may be an essential resource for mammals. Few studies, however, have focused on the use of caves by terrestrial mammals. The Yucatán Peninsula encompasses an extensive carbonate karst region that includes the world's largest underwater cave system. Forest in the region overlies fractured limestone bedrock, so flooded caves known regionally as cenotes represent the only reliable source of free‐standing water for much of the Peninsula's wildlife. We used camera traps at 17 cenotes on the Yucatán Peninsula to determine patterns of use by mammals. Eighteen non‐volant mammal taxa were identified using cenotes, the most commonly occurring being lowland paca (Agouti paca), opossums (Didelphis spp.), white‐nosed coati (Nasua narica), gray fox (Urocyon cinereoargenteus), tayra (Eira barbara), and gray four‐eyed opossum (Philander opossum); collectively these taxa accounted for 76% of all mammal records. We also recorded several felids using cenotes, including jaguar (Panthera onca) and puma (Puma concolor). Activity patterns at cenotes usually matched normal activity schedules, but some species were nocturnal in the forest but diurnal at cenotes. Mammals mostly accessed cenotes to drink, but a range of activities were recorded including foraging, nesting, mating, resting, and bathing. The Yucatán region has experienced continued population growth and economic development over many decades which directly threatens cenotes. Because our work has revealed that cenotes are important to the Yucatán's mammals, we believe protection of cenotes should be a central issue for regional wildlife conservation.Abstract in Spanish is available with online material.

Integrating presence-only and occupancy data to model habitat use for the northernmost population of jaguars.

Species distribution models (SDMs) have become an essential tool for the management and conservation of imperiled species. However, many at-risk species are rare and characterized by limited data on their spatial distribution and habitat relationships. This has led to the development of SDMs that integrate multiple types and sources of data to leverage more information and provide improved predictions of habitat associations. We developed a novel integrated species distribution model to predict habitat suitability for jaguars (Panthera onca) in the border region between northern Mexico and the southwestern USA. Our model combined presence-only and occupancy data to identify key environmental correlates, and we used model results to develop a probability of use map. We adopted a logistic regression modeling framework, which we found to be more straightforward and less computationally intensive to fit than Poisson point process-based models. Model results suggested that high terrain ruggedness and the presence of riparian vegetation were most strongly related to habitat use by jaguars in our study region. Our best model, on average, predicted that there is currently 25,463 km2 of usable habitat in our study region. The United States portion of the study region, which makes up 38.6% of the total area, contained 40.6% of the total usable habitat. Even though there have been few detections of jaguars in the southwestern USA in recent decades, our results suggest that protection of currently suitable habitats, along with increased conservation efforts, could significantly contribute to the recovery of jaguars in the USA.

Jaguars in the matrix: population, prey abundance and land-cover change in a fragmented landscape in western Mexico

AbstractHabitat fragmentation threatens biodiversity worldwide, particularly affecting large-bodied species that require vast territories and move across long distances, including most large felids. The jaguar Panthera onca has lost more than half of its habitat throughout its range and its subpopulations are becoming isolated, making them susceptible to local extinction. Knowledge about the status of its subpopulations in highly fragmented environments is lacking but urgently needed. Using camera traps during 2019–2020, we estimated number of individuals, age classes and sex ratio, occupancy, relative abundance and density of jaguars in Nayarit, western Mexico. We also determined the relative abundance of potential prey and estimated the land-cover change rate during 1999–2019, using GIS. We found that a resident subpopulation of five adult females, two adult males and one cub, at a high density (5.3 individuals/100 km2), is supported by at least 14 wild prey species. Natural habitat in the area is rapidly decreasing because of expanding agriculture and shrimp farming: agricultural areas increased from 39 to 50% and mangroves decreased from 35 to 26% of the study area over 20 years. The high jaguar population density and the diversity and relative abundance of remaining wild prey are remarkable, considering that natural habitat in the area is highly fragmented, shrinking rapidly and embedded in a matrix of human-dominated land-cover types. Effective conservation actions are needed urgently, including the protection of patches with native vegetation, reforestation to maintain connectivity between these patches, and the involvement of local communities.

Landscape patterns in the occupancy of jaguars (Panthera onca) and their primary prey species in a disturbed region of the Selva Maya in Mexico

Abstract In order to prioritize the conservation and management efforts to protect jaguars (Panthera onca), it is of utmost importance to determine their tolerance in face of human disturbances, habitat modifications and varying degrees of prey availability. We assessed the occupancy probability of jaguars and five of their most common prey species throughout a heterogeneous landscape in the Selva Maya in southern Mexico: armadillo (Dasypus novemcinctus), coati (Nasua narica), paca (Cuniculus paca), white-tailed deer (Odocoileus virginianus), and collared peccary (Dicotyles tajacu). Additionally, we projected prey and Jaguar occupancies onto a 5993 km2 landscape based on the habitat type in the area. We averaged the best prey models ranked by QAICc and found that white-tailed deer had the highest average occupancy probability of 0.72 ± 0.06 and paca the lowest with 0.14 ± 0.04. The average occupancy probability for jaguars was 0.35 ± 0.07 and the strongest predictor of jaguar occupancy was a positive effect of collared peccary occupancy. These findings support previous studies that show that predator distribution is largely influenced by their prey availability, even in the midst of degraded habitats, and underlies the essential need to incorporate protection plans for prey species in jaguar conservation strategies.

CO-OCCURRENCE OF FOUR ENDANGERED MAMMALS IN THE MEXICO–UNITED STATES BORDERLANDS: JAGUAR (PANTHERA ONCA), OCELOT (LEOPARDUS PARDALIS), BEAVER (CASTOR CANADENSIS) AND BLACK BEAR (URSUS AMERICANUS)

The unique biogeography of the Madrean Archipelago facilitates the cohabitation of species that otherwise rarely overlap in their spatial distributions. As part of a long-term study at Cuenca Los Ojos, Sonora, we deployed 25 cameras along washes within the property from October 2018 to April 2019, adding to the camera-trap information collected at the site since 2016. Ocelot (Leopardus pardalis) was recorded once in 2018, twice in 2016 and 2020, but not during the 2018–2019 study period. Black bear (Ursus americanus) was recorded regularly throughout the season with several images including cubs. One picture and several signs of beaver (Castor canadensis) were discovered in 2018 and 2019. Lastly, the first record of jaguar (Panthera onca) in Cuenca Los Ojos was recorded in February and March 2019 at four different sites. All species are considered endangered in Mexico and species of conservation concern in the United States and were recorded within 5 km south of the USA–Mexico border wall. Our addition of the new ocelot sighting in this region marks the only known location with records of all four species overlapping in space and time despite historical distribution ranges of black bears, jaguars, and beavers overlapping. Given the current border wall construction and highway development, which both affect the natural connectivity of the region, it will be necessary to incorporate the presence of the four species in all future mitigation efforts.

An Overview of Neoplasia in Captive Wild Felids in Southern Italy Zoos.

The aim of this study was to evaluate the frequency of neoplasms in captive wild felids in Southern Italy zoos over a 13-year period (2008–2021) and to investigate macroscopic and histologic tumor findings in these animals. A total of 24 cases were necropsied, 9 males and 15 females, with age ranging from 6 to 19 years, including 12 tigers (Panthera tigris), 7 leopards (Panthera pardus), 4 lions (Panthera leo), and 1 black jaguar (Panthera onca). Diagnosis of neoplasm was made in 14/24 cases (58.3%). Tumors diagnosed were two cholangiocarcinomas, two hemangiosarcomas of the liver, two uterine leiomyomas, a renal adenocarcinoma, an adrenal gland adenoma, a thyroid carcinoma, an oral squamous cell carcinoma, an osteoma, a meningioma, a mesothelioma, an esophageal leiomyosarcoma, a muscoloskeletal leiomyosarcoma and a thyroid adenoma. The malignant and benign tumors were 62.5 and 37.5%, respectively. Among malignant tumors, no metastasis was observed in 50% of cases; in 10% of cases metastasis involved only regional lymph nodes; and distant metastases were found in 40% of cases. Based on our findings, the liver was the most frequent primary tumor site (25%). The high rates of malignant and widely metastatic neoplasms suggest the importance of active monitoring and management of neoplasia in these threatened and endangered species.

Completely caught off guard: a new record of Jaguar, Panthera onca&amp;nbsp;(Linnaeus, 1758) (Mammalia, Felidae), from an urban park

Jaguar, Panthera onca (Linnaeus, 1758), is a paramount predator that contributes to ecosystem balance but rarely inhabits small conserved areas. We report a new record of a Jaguar in Brasilia National Park that was photographed while monitoring the Giant Anteater (Myrmecophaga tridactyla Linnaeus, 1758) population using camera traps. This Jaguar record is critical in documenting the presence of this species in highly human-inhabited and urbanized areas. Our new record also contributes to the understanding of the current distribution of remaining individuals and confirms the importance of large-scale protected areas in providing habitat for species, such as jaguars, that have large ranges.

Jaguar (Panthera onca) spatial ecology outside protected areas in the Selva Maya

Jaguars (Panthera onca) are endangered in several countries and a priority species for conservation action. Despite extensive research efforts in Mexico most studies have been associated with natural protected areas far from human habitation. Because protected areas are too few to conserve the jaguar population over the long–term, a landscape approach that includes both protected and unprotected lands is needed. This is the case in Quintana Roo State where an ecological corridor linking two protected areas (Yum Balam and Sian Ka'an) is at risk of disappearing due to tourism–driven activities. Between 2013 and 2015, four male jaguars were captured and monitored using satellite telemetry inside the corridor. The mean home range size (± SD) was 101.5 km2 (± 75.9 km2) for the dry season and 172 km2 (± 107.29 km2) for the rainy season. The mean core area size (± SD) was 17.54 km2 (± 16.21 km2) for the dry season and 29.07 km2 (± 16.19 km2) for the rainy season. No significant seasonal differences were found for home ranges or for core areas. As expected, we observed that jaguars preferred forest or young secondary growth over profusely disturbed areas, using whatever vegetation was available in their home ranges. Although it is not protected, a biological corridor linking Yum Balam and Sian Ka'an still holds its own jaguar population, a population that has learned to coexist with human presence. Conservation actions are recommended at landscape level to maintain what remains of tropical mature forest and to promote the development of long–term secondary growth into close tree canopy

Mesotelioma peritoneal em onça-pintada (Panthera onca – Linnaeus, 1758)

Mesotheliomas are malignant neoplasms and cause severe and extensive lesions in the peritoneum, pleura, pericardium and adjacent organs. The present case study discusses the death of a jaguar (Panthera onca) kept under human care in a zoo in the state of São Paulo, Brazil, with an estimated age of 19-years-old. He presented increased abdominal volume, ascites, decreased displacement by the enclosure, inappetence and polydipsia. The patient underwent clinical, laboratory and diagnostic imaging tests and died after a short period of time. The anatomopathological results indicated the diagnosis of peritoneal mesothelioma, with metastasis in the mesenteric lymph node.

Spatial distribution patterns of tick community structure in sympatric jaguars (Panthera onca) and pumas (Puma concolor) from three ecoregions in Mexico.

We examined tick communities on wild felid hosts in three ecoregions of Mexico. We collected 186 ticks of 7 species from 10 pumas (Puma concolor) and 9 jaguars (Panthera onca). Tick community composition varied across the ecoregions, and across host species within each region. Overall, Ixodes affinis, Amblyomma ovale, and Amblyomma tenellum were the most abundant species; however, only the latter two ticks were distributed across all three ecoregions, while I. affinis, along with Ixodes spinipalpis, Amblyomma inornatum, and Amblyomma parvum were restricted to more limited geographical regions. Ixodes affinis occurred strictly in southern tropical rainforest ecoregions and was significantly more abundant in Selva Lacandona compared with the Yucatán Peninsula. Amblyomma ovale was significantly more common in the tropical dry forest in the Pacific coastal ecoregion. Amblyomma tenellum abundance tended to be higher on jaguars, while I. affinis abundance was higher on pumas. Regional distribution patterns of some tick species (e.g., I. affinis and I. spinipalpis) may be determined by off-host environmental conditions rather than host factors. In contrast, at the local scale, occurrence and abundance of some tick species (e.g., A. tenellum, A. ovale and Rhipicephalus microplus) might be driven by ecological-host factors, such as habitat use or predator-prey relationships.