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1.
Jaguars (Panthera onca) and pumas (Puma concolor) are sympatric across the entire jaguar range, where they coexist in increasingly fragmented landscapes under threat of persecution mainly in response to livestock predation. Pumas are known to inhabit a greater variety of natural habitats than jaguars, but little is known about the influence of anthropogenic factors on the coexistence of these two similar-sized cats. This study compares habitat use of jaguars and pumas in Belize, Central America, using 1380 jaguar and puma photo captures from 3 yr of camera trapping, comprising 64–74 individual jaguars and an unknown number of pumas. Jaguars and pumas did not differ in their use of a large block of relatively homogenous secondary rain forest. However, pumas were scarce outside this forest block, whereas jaguars were detected throughout the human-influenced landscape. Reasons for this discrepancy may include differential tolerance to human disturbance, and resource limitation for pumas outside the forest block. Intra-specific variation in jaguar activity in the form of sex-dependent habitat use was detected across the landscape. Male jaguars were detected at more locations than female jaguars and more frequently at each location, with a declining difference from a 50-fold greater detection in the protected forest, through forest buffer, savannah, pastures, to negligible difference in the disturbed forest.  相似文献   

2.
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.  相似文献   

3.
Understanding coexistence between sympatric felines with similar body sizes, such as jaguars Panthera onca and pumas Puma concolor , requires knowledge of the way these predators consume and partition food resources. Yet the importance of livestock predation on jaguar and puma coexistence is poorly known. I investigated food habits and patterns of livestock depredation of jaguar and pumas in the Iguaçu National Park (INP) in southern Brazil. From 1997 to 2001, I collected scats opportunistically on trails and roads in INP and visited ranches on the border of INP. I found that jaguars relied mostly on large and medium-sized wild prey species, while pumas concentrated on medium-sized prey species. Livestock was the fifth most frequent prey found in jaguar scats but the most important one in terms of biomass consumed. Jaguar and puma diets differed significantly when all prey items were compared and also when livestock was excluded from the jaguar diet. Jaguar predation on livestock was considerably higher than predation by pumas. However, predation was not substantial relative to availability of livestock, and cattle likely constitute an alternative source of prey for jaguars. Degree of diet overlap between jaguar and puma in INP suggests that coexistence was likely driven by exploitative competition through some degree of food partitioning. My results highlight the importance of more actions toward increasing numbers of large ungulates to preserve the population of jaguars in INP.  相似文献   

4.
Jaguars (Panthera onca) and pumas (Puma concolor) coexist throughout the Neotropics. Using camera trapping in four Brazilian biomes, we compare the daily activity patterns of the jaguar and puma, and their relationships with their main prey species. We used a kernel density method to quantify daily activity patterns and to investigate overlap between these predators and their main prey. Both cats showed intensive nocturnal and crepuscular activity (0.69 and 0.14 kernel density, respectively, for jaguars; 0.68 and 0.19 kernel density, respectively, for pumas). Only in the Pantanal did we observe a pattern of concentrated diurnal activity for both species. We found little temporal segregation between jaguars and pumas, as they showed similar activity patterns with high coefficients of overlapping (average ?1 = 0.86; SE = 0.15). We also observed a significant overlap between the activity patterns of the predators and their main prey species, suggesting that both predators adjust their activity to reduce their foraging energy expenditure. Our findings suggest that temporal partitioning is probably not a generalized mechanism of coexistence between jaguars and pumas; instead, the partitioning of habitat/space use and food resources may play a larger role in mediating top predator coexistence. Knowledge about these behavior aspects is crucial to elucidating the factors that enable coexistence of jaguars and pumas. Furthermore, an understanding of their respective activity periods is relevant to management and associated research efforts.  相似文献   

5.
Human pressures have increasingly placed keystone species, such as large cats, under threat. Together with forest loss, prey depletion is one of the main threats to the survival of jaguars (Panthera onca) and pumas (Puma concolor) throughout the Neotropics. Generally, primates are not considered main prey for jaguar and puma, and their inclusion in the diet could be indicative of ongoing prey species decline. Here, we investigate the effect of habitat type and disturbance on primate predation by large cats. Surveys took place during the dry seasons (March to June) of 2010 and 2011, covering a total of 608.5 km across 24 localities in the Uxpanapa Valley, Mexico. We found 65 felid scat samples with the aid of a wildlife scat detection dog, and then examined them to identify predator species and classify the prey remains they contained. Primates represented the most frequent prey (35%) for both jaguar and puma in our study site and constituted approximately half of the biomass consumed by these felines in the area. Primate remains were more likely to be found in scats surrounded by the lowest percentage of conserved forest or in areas surrounded by more villages, showing the potential effects of human activities on these species' populations. The high proportion of primates found in scats within our study site could be an early indication that populations of ungulates and other “typical” prey are beginning to collapse, and urgent conservation interventions are needed for both large cats and primates before they become locally extinct. Abstract in Spanish is available with online material.  相似文献   

6.
7.
  1. Large carnivores play critical roles in terrestrial ecosystems but have suffered dramatic range contractions over the past two centuries. Developing an accurate understanding of large carnivore diets is an important first step towards an improved understanding of their ecological roles and addressing the conservation challenges faced by these species.
  2. The puma is one of seven large felid species in the world and the only one native to the non‐tropical regions of the New World. We conducted a meta‐analysis of puma diets across the species’ range in the Americas and assessed the impact of varying environmental conditions, niche roles, and human activity on puma diets. Pumas displayed remarkable dietary flexibility, consuming at least 232 different prey species, including one Critically Endangered and five Endangered species.
  3. Our meta‐analysis found clear patterns in puma diets with changing habitat and environmental conditions. Pumas consumed more larger‐bodied prey species with increasing distance from the equator, but consumption of medium‐sized species showed the opposite trend.
  4. Puma diets varied with their realized niche; however, contrary to our expectations, puma consumption of large species did not change with their trophic position, and pumas consumed more small prey and birds as apex predators. Consumption of domestic species was negatively correlated with consumption of medium‐sized wild species, a finding which underscores the importance of maintaining intact native prey assemblages.
  5. The tremendous dietary flexibility displayed by pumas represents both an opportunity and a challenge for understanding the puma’s role in ecosystems and for the species’ management and conservation. Future studies should explore the linkages between availability and selection of primary and other wild prey, and consequent impacts on predation of domestic species, in order to guide conservation actions and reduce conflict between pumas and people.
  相似文献   

8.
Understanding how large felids use space is essential for the design of conservation plans that are required for their survival. Jaguars (Panthera onca) and pumas (Puma concolor) are the largest felids in the Neotropics, and they are sympatric throughout the entire range of the jaguar. However, there is very little information about the spatial requirements of these two species in the tropical rainforests of Central America. Using satellite GPS collars, we compared the spatial ecology of jaguars and pumas in a tropical rainforest in southern Mexico. We found that jaguars had home ranges that were 2–6 times larger than those of pumas. The mean annual home range was 181.4 ± 4.0 km2 for female jaguars and 431.6 ± 152.6 km2 for males. Annual home range for the only female puma tracked was 34.3 km2, and 72.0 ± 85.2 km2 for males. Jaguars and pumas with overlapping home ranges showed little overlap of core areas and avoided using the same sites at the same time, which suggested that territoriality and avoidance were in play. Further evidence of avoidance was derived from our observation that pumas exhibited greater movement during the lightest periods of the day and jaguars moved most during the darkest. This temporal separation probably facilitates coexistence. Our data suggest that habitat destruction and fragmentation has more severe effects on jaguars than on pumas. According to our estimates, patches of at least 180 km2 of primary forest are required to meet the annual spatial requirements of female jaguars. Thus, to conserve jaguars in this region, large tracts of primary forest should be preserved. Importantly, this population of jaguars depends on the adequate preservation of connectivity between natural reserves in Mexico and Guatemala.  相似文献   

9.
Pumas (Puma concolor; also known as mountain lions and cougars) in southern California live among a burgeoning human population of roughly 20 million people. Yet little is known of the consequences of attendant habitat loss and fragmentation, and human-caused puma mortality to puma population viability and genetic diversity. We examined genetic status of pumas in coastal mountains within the Peninsular Ranges south of Los Angeles, in San Diego, Riverside, and Orange counties. The Santa Ana Mountains are bounded by urbanization to the west, north, and east, and are separated from the eastern Peninsular Ranges to the southeast by a ten lane interstate highway (I-15). We analyzed DNA samples from 97 pumas sampled between 2001 and 2012. Genotypic data for forty-six microsatellite loci revealed that pumas sampled in the Santa Ana Mountains (n = 42) displayed lower genetic diversity than pumas from nearly every other region in California tested (n = 257), including those living in the Peninsular Ranges immediately to the east across I-15 (n = 55). Santa Ana Mountains pumas had high average pairwise relatedness, high individual internal relatedness, a low estimated effective population size, and strong evidence of a bottleneck and isolation from other populations in California. These and ecological findings provide clear evidence that Santa Ana Mountains pumas have been experiencing genetic impacts related to barriers to gene flow, and are a warning signal to wildlife managers and land use planners that mitigation efforts will be needed to stem further genetic and demographic decay in the Santa Ana Mountains puma population.  相似文献   

10.
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.  相似文献   

11.
ABSTRACT The jaguar (Panthera onca) and puma (Puma concolor) are the largest felids of the American Continent and live in sympatry along most of their distribution. Their tracks are frequently used for research and management purposes, but tracks are difficult to distinguish from each other and can be confused with those of big canids. We used tracks from pumas, jaguars, large dogs, and maned wolves (Chrysocyon brachyurus) to evaluate traditional qualitative and quantitative identification methods and to elaborate multivariate methods to differentiate big canids versus big felids and puma versus jaguar tracks (n = 167 tracks from 18 zoos). We tested accuracy of qualitative classification through an identification exercise with field-experienced volunteers. Qualitative methods were useful but there was high variability in accuracy of track identification. Most of the traditional quantitative methods showed an elevated percentage of misclassified tracks (≥20%). We used stepwise discriminant function analysis to develop 3 discriminant models: 1 for big canid versus big felid track identification and 2 alternative models for jaguar versus puma track differentiation using 1) best discriminant variables, and 2) size-independent variables. These models had high classification performance, with <10% of error in the validation procedures. We used simpler discriminant models in the elaboration of identification keys to facilitate track classification process. We developed an accurate method for track identification, capable of distinguishing between big felids (puma and jaguar) and large canids (dog and maned wolf) tracks and between jaguar and puma tracks. Application of our method will allow a more reliable use of tracks in puma and jaguar research and it will help managers using tracks as indicators of these felids' presence for conservation or management purposes.  相似文献   

12.
Serum samples from 19 jaguars (Panthera onca), nine pumas (Puma concolor), and two ocelots (Leopardus pardalis) were collected between January 1999 and March of 2005 and tested for presence of canine distemper virus (CDV). All cats were free-ranging animals living in two protected areas in the Brazilian Atlantic Forest. In addition, 111 domestic dogs from nearby areas were sampled for CDV. Our results show the first evidence of CDV exposure in Brazilian free-ranging felids. From the 30 samples analyzed, six jaguars and one puma were tested seropositive for CDV. All seropositive large felids were from Ivinhema State Park, resulting in 31.5% of the sampled jaguars or 60% of the total jaguar population in Ivinhema State Park, and 11.28% of the sampled pumas. From the total 111 domestic dogs sampled, 45 were tested seropositive for CDV. At Morro do Diabo State Park, 34.6% of the dogs sampled were positive for CDV, and 100% at Ivinhema State Park. Canine distemper virus in wild felids seems to be related with home range use and in close association with domestic dogs living in nearby areas.  相似文献   

13.
Abstract: Because of increasing concerns about puma (Puma concolor) attacks on people and the desire to minimize dangerous puma-human encounters while conserving puma populations, we examined spatial and temporal relationships between pumas and people that used Cuyamaca Rancho State Park (CRSP), California, USA. From 2001 to 2003, we studied 10 adult pumas outfitted with Global Positioning System collars. Although number of visitors to CRSP was increasing, no dangerous puma-human encounters were reported during our study. Male and female pumas typically moved short distances during the day (mean of means of individual hourly movements = 168 m and 131 m each hr, respectively) and moved the most at night (mean of means = 690 m and 390 m each hr, respectively). Of 10 pumas, 9 were least active during the day and most active during the evening or at night. In contrast, most visitor use of trails (x̄ = 85%) occurred during the day. Based on puma and human activity patterns, risk of a puma-human encounter was greatest during the evening. Puma prey caches were randomly distributed in relation to trails and park facilities; however, 8 of 33 caches were still within 100 m of a trail and 2 were within 300 m of a facility. Individual puma behavior relative to human activity areas was variable. Some pumas appeared to temporally avoid human activity areas; others used the park randomly in relation to human activity areas; none appeared to be attracted to human activity areas. Pumas that did not show detectable responses to human activity may have been exhibiting some level of habituation; if so, this level of habituation did not result in puma-human conflicts. When human activity peaked during the day, adult male and female pumas were within 100 m of a trail an average of 9% and 19% of the time they were located in the park, respectively. Thus, there were opportunities for puma-human encounters. Management personnel can take a proactive approach to deal with puma-human interactions through education and protocols that help to minimize probability of conflicts; this may provide the best chance for a continued puma presence in habitat used by pumas and people.  相似文献   

14.
Space use and diets of sympatric bobcats Lynx rufus and pumas Puma concolor were compared using sign surveys and scat analysis during 1997–2002 in south-eastern Arizona, USA. Bobcats appeared to use grassland, scrub, riparian and woodland habitats equally, but pumas had higher activity in riparian and woodland habitats. There was little evidence that bobcats avoided pumas in space use. Bobcats ate primarily rodents (33% of items in scats), lagomorphs (32%) and ungulates (16%), whereas pumas ate primarily ungulates (69%) and carnivores (21%). Pumas had a narrower dietary niche breadth than bobcats, and puma diet overlapped bobcat diet by 56%, suggesting that pumas may be more vulnerable to changes in prey density than bobcats. Pumas also killed and consumed bobcats, indicating that interference competition may be manifesting through intraguild predation.  相似文献   

15.
Apex predators are important indicators of intact natural ecosystems. They are also sensitive to urbanization because they require broad home ranges and extensive contiguous habitat to support their prey base. Pumas (Puma concolor) can persist near human developed areas, but urbanization may be detrimental to their movement ecology, population structure, and genetic diversity. To investigate potential effects of urbanization in population connectivity of pumas, we performed a landscape genomics study of 130 pumas on the rural Western Slope and more urbanized Front Range of Colorado, USA. Over 12,000 single nucleotide polymorphisms (SNPs) were genotyped using double‐digest, restriction site‐associated DNA sequencing (ddRADseq). We investigated patterns of gene flow and genetic diversity, and tested for correlations between key landscape variables and genetic distance to assess the effects of urbanization and other landscape factors on gene flow. Levels of genetic diversity were similar for the Western Slope and Front Range, but effective population sizes were smaller, genetic distances were higher, and there was more admixture in the more urbanized Front Range. Forest cover was strongly positively associated with puma gene flow on the Western Slope, while impervious surfaces restricted gene flow and more open, natural habitats enhanced gene flow on the Front Range. Landscape genomic analyses revealed differences in puma movement and gene flow patterns in rural versus urban settings. Our results highlight the utility of dense, genome‐scale markers to document subtle impacts of urbanization on a wide‐ranging carnivore living near a large urban center.  相似文献   

16.
This study sought to identify critical areas for puma (Puma concolor) movement across the state of Arizona in the American Southwest and to identify those most likely to be impacted by current and future human land uses, particularly expanding urban development and associated increases in traffic volume. Human populations in this region are expanding rapidly, with the potential for urban centers and busy roads to increasingly act as barriers to demographic and genetic connectivity of large‐bodied, wide‐ranging carnivores such as pumas, whose long‐distance movements are likely to bring them into contact with human land uses and whose low tolerance both for and from humans may put them at risk unless opportunities for safe passage through or around human‐modified landscapes are present. Brownian bridge movement models based on global positioning system collar data collected during bouts of active movement and linear mixed models were used to model habitat quality for puma movement; then, a wall‐to‐wall application of circuit theory models was used to produce a continuous statewide estimate of connectivity for puma movement and to identify pinch points, or bottlenecks, that may be most at risk of impacts from current and future traffic volume and expanding development. Rugged, shrub‐ and scrub‐dominated regions were highlighted as those offering high quality movement habitat for pumas, and pinch points with the greatest potential impacts from expanding development and traffic, although widely distributed, were particularly prominent to the north and east of the city of Phoenix and along interstate highways in the western portion of the state. These pinch points likely constitute important conservation opportunities, where barriers to movement may cause disproportionate loss of connectivity, but also where actions such as placement of wildlife crossing structures or conservation easements could enhance connectivity and prevent detrimental impacts before they occur.  相似文献   

17.
There is a great need to develop efficient, noninvasive genetic sampling methods to study wild populations of multiple, co‐occurring, threatened felids. This is especially important for molecular scatology studies occurring in challenging tropical environments where DNA degrades quickly and the quality of faecal samples varies greatly. We optimized 14 polymorphic microsatellite loci for jaguars (Panthera onca), pumas (Puma concolor) and ocelots (Leopardus pardalis) and assessed their utility for cross‐species amplification. Additionally, we tested their reliability for species and individual identification using DNA from faeces of wild felids detected by a scat detector dog across Belize in Central America. All microsatellite loci were successfully amplified in the three target species, were polymorphic with average expected heterozygosities of HE = 0.60 ± 0.18 (SD) for jaguars, HE = 0.65 ± 0.21 (SD) for pumas and HE = 0.70 ± 0.13 (SD) for ocelots and had an overall PCR amplification success of 61%. We used this nuclear DNA primer set to successfully identify species and individuals from 49% of 1053 field‐collected scat samples. This set of optimized microsatellite multiplexes represents a powerful tool for future efforts to conduct noninvasive studies on multiple, wild Neotropical felids.  相似文献   

18.
Aaron M. HAINES 《动物学报》2006,52(6):1142-1147
美洲虎( Panthera onca)和美洲狮( Puma concolor)是中美洲和南美洲大部区域共存的大型猫科动物,其共存理论得到研究验证。本文作者回顾了有关文献,认为同域分布的美洲虎和美洲狮存在生境和猎物分化,提出热带美洲狮具有较小体型以利用较小的猎物并减少与美洲虎竞争的假设。研究支持美洲虎和美洲狮的空间相互回避概念,但两者猎物之间分化的研究结果不相吻合。尽管如此,文献认为新热带界美洲狮体型较小只是反映了在进化过程中偏于利用较小猎物的事实,而与美洲虎的竞争无关。人类的影响会引起美洲虎和美洲狮的共存。在新热带界环境中,美洲虎由于依赖特定猎物而较大程度地受到人类引起的猎物种群下降之影响,但美洲狮由于可以偏向利用小型猎物或猎物多样化而得到补偿,从而能更好地适应人类的影响。  相似文献   

19.
The killing of an adult male spider monkey (Ateles belzebuth ) by a jaguar (Panthera onca) and a predation attempt by a puma (Felis concolor) on an adult female spider monkey have been observed at the CIEM (Centro de Investigaciones Ecológicas La Macarena), La Macarena, Colombia. These incidents occurred directly in front of an observer, even though it is said that predation under direct observation on any type of primate rarely occurs. On the basis of a review of the literature, and the observations reported here, we suggest that jaguars and pumas are likely to be the only significant potential predators on adult spider monkeys, probably because of their large body size.  相似文献   

20.
ABSTRACT Information on factors affecting population size of pumas (Puma concolor) can be important because their principal prey over most of the western United States are valued big game species (e.g., mule deer [Odocoileus hemionus], elk [Cervus elaphus], and bighorn sheep [Ovis canadensis]). Based on the hypothesis that puma numbers are limited by their food supply, puma populations should track changes in prey abundance by growing exponentially with increases in prey and by declining with a lag response when prey decreases. Additional predictions proposed by researchers are that body mass of pumas, female productivity, kitten survival, and adult survival should decrease after a prey decline. We used a 15-year database from a hunted population of pumas in southern Idaho and northwestern Utah to test these predictions. During the 15-year time span of the database, a major decline in mule deer abundance occurred. Estimates of puma numbers and demographic characteristics came from intensive capture and radiocollaring efforts. We calculated kitten and adult survival with MICROMORT software. We found that adult puma numbers increased exponentially at r = 0.07 during a period of increasing mule deer numbers. Four years after the mule deer abundance declined, puma numbers decreased at a rate of r = −0.06. Body mass of female pumas was lower after the decline in puma numbers (42.6 ± SE = 1.2 kg, n = 40 vs. 40.1 ± 0.64 kg, n = 34, t = 5.06, P = 0.045). Kitten survival was less after the decline in deer abundance (0.573 ± 0.016, n = 30 vs. 0.856 ± 0.015, n = 25, Z = 2.40, P < 0.01). Survival of resident females was significantly less after the decline in puma numbers (0.783 ± 0.03 vs. 0.929 ± 0.019, U = 55.0, P = 0.009). Female productivity did not differ before or after the decline in deer abundance. Our results supported the majority of the predictions concerning the impact of changing deer abundance, which supported the hypothesis that the abundance of mule deer limited our population of pumas.  相似文献   

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