Tayassu Research Articles

How to not inflate population estimates? Spatial density distribution of white-lipped peccaries in a continuous Atlantic forest

In a world with poor biological inventorying and rapid land-use change, predicting the spatial distribution of species is fundamental for the effective management and conservation of threatened taxa. However, on a regional scale, predicting the distribution of rare terrestrial mammals is often unreliable and/or impractical, especially in tropical forests. We apply a recently developed analytic process that integrates density estimation (kernel smoothing), niche-analysis and geostatistics (regression-kriging) to model the occupancy and density distribution of a threatened population of white-lipped peccaries Tayassu pecari in a Brazilian Atlantic forest. Locations (n=45) within a protected area of the Serra-do-Mar state park were obtained from diurnal line transect census (233 km), camera-trapping (751 camera-trap days) and surveys (>626 km) conducted by park rangers. Niche modelling (environmental niche-factor analysis and MAXENT) revealed a restricted niche compared with the available habitat as defined by seven environmental variables. From the occupancy model obtained from regression-kriging, we found that 72% of a 170 km2 protected area is likely to be used by peccaries. We demonstrate that the distribution of large mammals can be restricted within continuous areas of Atlantic forest and therefore population estimates based on the size of protected areas can be overestimated. Our findings suggest that the generation of realized density distributions should become the norm rather than the exception to enable conservation managers and researchers to extrapolate abundance and density estimates across continuous habitats and protected areas.

Use of a Mycoplasma suis-PCR protocol for screening a population of captive peccaries (Tayassu tajacu and Tayassu pecari)

Mycoplasma suis is a hemotropic bacteria of red blood cells and the causative agent of swine eperythrozoonosis. Diagnosis of infection may be reached by direct examination of blood smears; however, the use of polymerase chain reaction (PCR) of the 16S RNA gene of M. suis improves the sensitivity and specificity of detection. The aim of this study was to screen peccaries (Tayassu tajacu and T. pecari) for M. suis infection using a specific conventional PCR. A total of 28 blood samples from captive collared and white-lipped peccaries were collected, DNA extracted and a specific M. suis PCR assay performed. All samples were negatives by both blood smear examination and PCR testing. To verify the presence of amplifiable DNA, PCR for beta-actin gene was performed in all samples. This study was part of an active surveillance program, which is crucial for monitoring animal health status, particularly in wildlife species.

Kinetics of spermatogenesis in the white-lipped peccary ( Tayassu pecari)

This study aimed to characterize the stages of the seminiferous epithelium cycle by the tubular morphology method, and to determine the number of differentiated spermatogonia generations in the adult white-lipped peccary. Twenty adult white-lipped peccaries, obtained from commercial slaughterhouse, were used. Fragments of the testicular parenchyma were fixed in 3% glutaraldehyde and embedded into a methacrylate resin. The number of germ and Sertoli cells was estimated by the analysis of cell populations in 50 transversal sections of seminiferous tubules in different stages of the cycle. The tubular morphology method allowed the identification of cellular associations characteristic of the eight stages of the seminiferous epithelium cycle in white-lipped peccaries. The results showed the presence of six generations of differentiated spermatogonia in white-lipped peccaries, and that the cell composition of the eight stages of the seminiferous epithelium cycle in this species is very similar to that described for collared peccaries.

Integrating occupancy modeling and interview data for corridor identification: A case study for jaguars in Nicaragua

Corridors are critical elements in the long-term conservation of wide-ranging species like the jaguar (Panthera onca). Jaguar corridors across the range of the species were initially identified using a GIS-based least-cost corridor model. However, due to inherent errors in remotely sensed data and model uncertainties, these corridors warrant field verification before conservation efforts can begin. We developed a novel corridor assessment protocol based on interview data and site occupancy modeling. We divided our pilot study area, in southeastern Nicaragua, into 71, 6×6km sampling units and conducted 160 structured interviews with local residents. Interviews were designed to collect data on jaguar and seven prey species so that detection/non-detection matrices could be constructed for each sampling unit. Jaguars were reportedly detected in 57% of the sampling units and had a detection probability of 28%. With the exception of white-lipped peccary, prey species were reportedly detected in 82–100% of the sampling units. Though the use of interview data may violate some assumptions of the occupancy modeling approach for determining ‘proportion of area occupied’, we countered these shortcomings through study design and interpreting the occupancy parameter, psi, as ‘probability of habitat used’. Probability of habitat use was modeled for each target species using single state or multistate models. A combination of the estimated probabilities of habitat use for jaguar and prey was selected to identify the final jaguar corridor. This protocol provides an efficient field methodology for identifying corridors for easily-identifiable species, across large study areas comprised of unprotected, private lands.

Invasive species and bushmeat hunting contributing to wildlife conservation: the case of feral pigs in a Neotropical wetland

AbstractAn unusual combination of two major conservation threats, invasive species and bushmeat hunting, has had a positive outcome for wildlife conservation in the Brazilian Pantanal. The Pantanal is a wetland and one of the few non-protected areas in the Neotropics where people live but rarely hunt native wildlife. To understand why wildlife hunting is not a major conservation issue in the Pantanal an exploratory survey, semi-structured interviews, skull collection and tooth wear analysis of feral pig Sus scrofa, white-lipped peccary Tayassu pecari and collared peccary Pecari tajacu were conducted, and hunting registers distributed, in the central region of the Pantanal. The results showed that feral pigs are the main hunting target. Feral pigs are effectively acting as a replacement species for hunting of native wildlife because the pigs provide a constant, culturally acceptable, readily available and free source of meat and oil to remote ranches. We cannot evaluate, however, if the buffer from hunting that feral pigs provide to native wildlife outweigh this species’ potential negative ecological impacts.

Protozoários gastrointestinais em Tayassu pecari mantidos em cativeiro no Brasil

The aim of this study was to report the gastrointestinal parasitism in white-lipped peccary (Tayassu pecari) in Brazil. Fecal samples of three animals kept in captivity in the state of Rio Grande do Sul were collected. Samples were analyzed by the centrifugal flotation technique with zinc sulfate and by the Kinyon staining method. All animals showed mixed infection by cysts of Giardia sp. and Balantidium sp. and by oocysts of Cryptosporidium sp. and Eimeria sp. This is the first report of these four genera of protozoa in T. pecari.

Áreas de uso do Tayassu pecari em fragmentos de Floresta com Araucária, Paraná, Brasil

This study aimed to investigate the area of use, relative abundance, spatial distribution and area size of the white-lipped peccary (Tayassu pecari Link, 1795) along the Araucaria Ecological Corridor. The research was carried out in 14 properties located on a spatial section of 659 km2 situated in the Third Plateau of the state of Paraná. The points of occurrence of peccary were mapped based on interviews with local inhabitants and on tracks, paths, and other signs of its presence in the sampling areas. The areas were monthly visited (18 months) and the points (UTM) with signs of the species were marked by GPS and plotted on the map. The relative abundance index was estimated based on all the events in which the species was seen. Considering the values of relative  abundance index for both groups of peccary studied, an average of 119 individuals was estimated for an area of 232 km2. The relative density obtained was considered low, especially considering that the peccary is a social species. It is possible that hunting is the main cause of the population decline of the species in the studied region.

Assessing Local Knowledge of Game Abundance and Persistence of Hunting Livelihoods in the Bolivian Amazon Using Consensus Analysis

We used cultural consensus models to test whether hunters shared perceptions of wildlife abundance and the relative importance of hunting and fishing in a Guarayo indigenous community in the Bolivian Amazon. Results show that highly prized animals that were considered rare are either those with lower reproductive rates and more sensitivity to land use changes and harvest (white-lipped peccary and spider monkey) or those with marked seasonal distribution patterns (barred sorubim and tiger-fish). Rapidly reproducing and resilient species (agouti and armored catfish) were perceived as abundant. More tapirs and red brocket deer were present than predicted by scientific models possibly because hunters were harvesting these species in new forest management areas. Residents identified hunting and fishing among their most important livelihood activities, recognized bush meat and fish as basic food resources, and expected wildlife harvests to be part of their future livelihoods, although market-based livelihoods and domestic replacements for bush meat were reported.

Using ungulate occurrence to evaluate community-based conservation within a biosphere reserve model

Conservation areas in tropical forests protect the most diverse and threatened ecosystems on the planet. In the Amazon, ungulates are important determinants of forest structure and plant diversity, as well as being a resource for rural communities. Using occupancy-based methods, we estimated the occurrence of white-lipped peccary Tayassu pecari, collared peccary Pecari tajacu, lowland tapir Tapirus terrestris and red brocket deer Mazama americana in and around protected areas reserve in Tambopata, Peru, to evaluate how different management designation, anthropogenic influences and habitat type influenced the occurrence of each species. We used a combination of track surveys (n=258) and camera surveys (n=256) to estimate ungulate presence at 55 sites in a national reserve, a native community and adjacent buffer areas from May 2008 to March 2009. We found that prediction of the occurrence of white-lipped peccary, lowland tapir and red brocket deer was best accomplished using travel time from the nearest city (a measure of an area's accessibility). The occurrence of ungulates differed little between buffer and reserves, but community lands managed by indigenous peoples showed reduced probabilities of ungulate occurrence. Our results indicate that passive protection afforded by inaccessibility might be an effective management strategy for this region; however, we doubt that this is tenable as a long-term solution.

Isolation and characterization of microsatellite loci for white-lipped peccaries (Tayassu pecari) and cross-amplification in collared peccaries (Pecari tajacu)

White-lipped peccaries, Tayassu pecari, are neotropical ungulates whose populations have been declining in numerous locations within their geographical distribution. Here we describe 16 microsatellite loci isolated from T. pecari and their cross-amplification in collared peccaries, Pecari tajacu. In 30 individuals of T. pecari, a total of 32 alleles were found in ten polymorphic loci, ranging from 2 to 8 alleles per locus with a mean of 3.2. The expected and observed heterozygosity ranged from 0.143 to 0.802 and from 0 to 0.704, respectively. Two loci deviated from Hardy–Weinberg equilibrium. In P. tajacu, nine loci were polymorphic with a mean of 3.2 alleles per locus. These molecular markers will be useful to study the genetic status of peccary populations and, consequently, to help their conservation.

Toxoplasma gondii Antibodies in Wild White-Lipped Peccary (Tayassu pecari) From Peru

In the Peruvian Amazon, the white-lipped peccary (Tayassu pecari) is a desirable game species and is important for the local rural economy. Blood samples from 101 white-lipped peccaries from Peru were collected from 3 different conservation areas located in the municipalities of Manu and Tambopata, southeastern region of the Peruvian Amazon. Antibodies were assayed using the modified agglutination test (MAT, cut of value of 25). Antibodies to Toxoplasma gondii were found in 89.1% (90 of 101) of animals, with titers of 1 ∶ 25 in 9, 1 ∶ 50 in 25, 1 ∶ 100 in 20, 1 ∶ 200 in 14, 1 ∶ 400 in 12, 1 ∶ 800 in 9, and 1 ∶ 3,200 in 1; 87.7% and 89.2% of males and females, respectively, tested positively, and no association (P ≥ 0.05) with gender and occurrence of antibodies was observed.

Ticks of the genus Amblyomma (Acari: Ixodidae) infesting tapirs (Tapirus terrestris) and peccaries (Tayassu pecari) in Peru

Abstract During 2008–2009, ticks were opportunistically collected from free-living lowland tapirs (Tapirus terrestris) and white-lipped peccaries (Tayassu pecari) during two studies of the ecology of Amazonian ungulates near or within two conservation areas in Madre de Dios, Peru. From tapirs, adults of the following tick species were collected: Amblyomma coelebs, Amblyomma incisum, Amblyomma latepunctatum, Amblyomma oblongoguttatum, Amblyomma ovale, and Amblyomma scalpturatum. Ticks collected from peccaries included adults of Amblyomma naponense and A. oblongoguttatum, nymphs of A. coelebs and A. latepunctatum, and larvae of Amblyomma sp. The 7 Amblyomma species collected in the present study have been previously reported in Peru. Although it is a common parasite of tapirs and/or peccaries in the Neotropical Region, we provide the first report of A. oblongoguttatum on tapirs in Peru. In addition, we provide the first report of A. coelebs and A. latepunctatum nymphs on peccaries. For nymphs of the latter ...

Prevalence of Leptospira interrogans antibodies in free-ranging Tayassu pecari of the Southern Pantanal, Brazil, an ecosystem where wildlife and cattle interact

We surveyed a wild population of white-lipped peccaries (Tayassu pecari) in the Brazilian Pantanal for evidence of Leptospira interrogans. Serum samples from 71 free-ranging T. pecari were obtained between 2003 and 2005 in the southern Pantanal of Mato Grosso do Sul state. We used microscopic microagglutination to test for antibodies against 14 L. interrogans serovars (antibody titers ≥ 1:100 were considered seropositive). Seventy percent of captured animals tested positive for leptospirosis antibodies. Antibodies against icterohaemorrhagiae and autumnalis serovars were the most prevalent. We used log-linear analyses to test for associations among seropositivity, age class, and sex of captured animals. Seropositivity was strongly associated with animal age class, but independent of sex. Forty-six percent of animals less than 2 years old, 63% of adults during peak reproductive years, and 100% of the oldest age class were seropositive. A nonparametric multivariate procedure (MRPP) showed that the composition of serovar antibody types changed with age, and ANOVA models demonstrated that antibody titers increased with age, suggesting long-term exposure to a greater number and variety (i.e., serovar types) of L. interrogans infections. This study presents the first quantitative survey of antibodies against L. interrogans serovars in a T. pecari population of the Pantanal. The high prevalence of leptospirosis antibodies in free-ranging white-lipped peccaries and the potential impacts on reproduction and population dynamics emphasize the need for further studies investigating the roles of Pantanal wildlife and livestock in the transmission and maintenance of L. interrogans in the environment.

Food habits of sympatric jaguars and pumas across a gradient of human disturbance

Jaguars Panthera onca coexist with pumas Puma concolor across their entire range. In areas where they occur together their coexistence may be facilitated by differences in diet. This study compared food habits of jaguars and pumas in Belize, Central America, across a protected lowland rainforest and the neighbouring human-influenced landscape. Diets were determined from 362 jaguar scats and 135 puma scats, identified by genetic analysis. In the protected forest, dietary breadths were low for jaguars and pumas and showed little overlap. In this habitat each relied heavily on a single medium-sized (5–10 kg) prey species: armadillos Dasypus novemcinctus for jaguars, and pacas Agouti paca for pumas. Both cats also took larger prey (>10 kg), mainly white-lipped peccaries Tayassu pecari by jaguars and red brocket deer Mazama americana by pumas. In unprotected fragmented lands, jaguar scats rarely contained large wild prey species; rather, a diet of relatively small wild prey was supplemented with larger domestic species. Pumas did not take domestic species and were scarce outside the protected forest, possibly indicating competition with humans for pacas and deer, which are also prized game species in the region. This study is the largest analysis to date of sympatric jaguar and puma diets in both forest and farmland. We suggest that jaguar predation on cattle may be reduced by ensuring that game hunting is sustainable and potentially by augmenting forests within the human matrix with large wild ungulates. The supplementation could benefit both of the cat species, and the local game hunting economy.

PERFIL DA CAÇA E DOS CAÇADORES NA RESERVA DE DESENVOLVIMENTO SUSTENTÁVEL AMANÃ, AMAZONAS – BRASIl.

Hunting wildlife is forbidden by Brazilian federal legislation, although it is tolerated in specific situations. the activity is important as a source of protein to rural populations. the objective of this study is to describe hunting in four communities of Amanã Sustainable Development Reserve. Structured interviews were carried out with hunters themselves, as well as other members of the communities (n=238). In addition to that, a survey of hunted game was also carried out during the period of this study. In six months of monitoring of the four communities, 373 individuals were harvested; totalling 5,932.75 Kg. Mammals were the main group hunted, representing 91,42% of the total weight produced in hunting events. the results of the study indicate that the species most susceptible to hunting are Tayassu pecari, Dasyprocta fuliginosa, Cuniculus paca, Tapirus terrestres, Alouatta seniculus, Mazama americana and Mazama gouazoubira, the river turtles of genus Podocnemis, and also the Cracidae and Anatidae.

Hosts, distribution and genetic divergence (16S rDNA) of Amblyomma dubitatum (Acari: Ixodidae)

We supply information about hosts and distribution of Amblyomma dubitatum. In addition, we carry out an analysis of genetic divergence among specimens of A. dubitatum from different localities and with respect to other Neotropical Amblyomma species, using sequences of 16S rDNA gene. Although specimens of A. dubitatum were collected on several mammal species as cattle horse, Tapirus terrestris, Mazama gouazoubira, Tayassu pecari, Sus scrofa, Cerdocyon thous, Myocastor coypus, Allouata caraya, Glossophaga soricina and man, most records of immature and adult stages of A. dubitatum were made on Hydrochoerus hydrochaeris, making this rodent the principal host for all parasitic stages of this ticks. Cricetidae rodents (Lundomys molitor, Scapteromys tumidus), opossums (Didelphis albiventris) and vizcacha (Lagostomus maximus) also were recorded as hosts for immature stages. All findings of A. dubitatum correspond to localities of Argentina, Brazil, Paraguay and Uruguay, and they were concentrated in the Biogeographical provinces of Pampa, Chaco, Cerrado, Brazilian Atlantic Forest, Parana Forest and Araucaria angustifolia Forest. The distribution of A. dubitatum is narrower than that of its principal host, therefore environmental variables rather than hosts determine the distributional ranges of this tick. The intraspecific genetic divergence among 16S rDNA sequences of A. dubitatum ticks collected in different localities from Argentina, Brazil and Uruguay was in all cases lower than 0.8%, whereas the differences with the remaining Amblyomma species included in the analysis were always bigger than 6.8%. Thus, the taxonomic status of A. dubitatum along its distribution appears to be certain at the specific level.

Evaluation of genetic variability in the collared peccary Pecari tajacu and the white-lipped peccary Tayassu pecari by microsatellite markers

In this study, the microsatellite technique was used to evaluate the genetic variability in populations of collared and white-lipped peccaries kept in captivity. Six primers developed for domestic pigs were used and amplified in both species. They revealed the presence of five polymorphic loci and one monomorphic locus. The polymorphic loci included 4 of the 16 alleles in collared peccaries, and 3 of the 10 alleles in the white-lipped peccaries. Polymorphic information content (PIC) in both species and all the loci was highly informative. The probability of paternity exclusion (PEC), if one of the parents is known, was almost as high in white-lipped peccaries (95.53%) as in the collared (99,48%). The Fst values for collared (0.042) and white-lipped (0.1387) peccaries showed that both populations are not structured. The Fis values for all loci, except ACTG2 in white-lipped peccaries (-0.0275) and in both species (0.1985 to 0.9284 in collared peccaries and 0.3621 to 0.4754 in the white-lipped), revealed a high level of homozygosis, probably caused by inbreeding. Data on heterologous amplification and genetic variability in collared and white-lipped peccaries are presented for the first time.

Function, size and form of the gastrointestinal tract of the collared Pecari tajacu (Linnaeus 1758) and white-lipped peccary Tayassu pecari (Link 1795)

The peccary digestive tract is characterised by an elaborate forestomach. In order to further characterise the digestive function of peccaries, we report body mass, digestive organ mass, content mass of the gastrointestinal tract compartments and their length and width, as well as liver, parotis and mandibular gland mass. Our data on eleven collared and four white-lipped peccaries suggest that peccaries have a small relative stomach volume compared to other foregut fermenters, which implies a comparatively lower fermentative capacity and thus forage digestibility. The forestomach could enable peccaries to deal, in conjunction with their large parotis glands, with certain plant toxins (e.g. oxalic acid). The finding of sand being trapped in the forestomach blindsacs could indicate a disadvantage of the peccary forestomach design. The relevance of the forestomach to peccaries remains enigmatic.

Hunting and the conservation of a social ungulate: the white-lipped peccary Tayassu pecari in Calakmul, Mexico

The white-lipped peccary Tayassu pecari is a social ungulate that forms the largest groups documented for any tropical forest ungulate species. Since the 1950s the species has become increasingly rare in Mesoamerica, and the more frequent reporting of smaller groups may be related to increased hunting pressure. Here we address the conservation status of this species in terms of its group size and structure, breeding season, population density, and relationship with hunting patterns in the Calakmul region of southern Mexico. Group sizes, age structure and breeding season were recorded in one large non-hunted site (Calakmul Biosphere Reserve) and four adjacent hunted sites. Population density was estimated in the Reserve and hunting patterns were recorded from three adjacent villages. Results indicate that hunting pressure affects peccary populations by reducing group size. White-lipped peccary groups were larger in the Reserve (median = 25) than in the hunted areas (median = 16) but groups were generally smaller than those reported in other forests. These smaller group sizes indicate conservation concern for this species in the Calakmul region. In addition, the estimated population (0.43 km2) is one of the lowest reported for this species. Hunting occurs mainly in the dry season, which is the peak of the breeding season and when peccary groups visit water bodies, where they are more easily hunted.

Anatomicohistological Characteristics of the Female Genital Organs of the White‐lipped Peccary (Tayassu pecari) in the Peruvian Amazon

This study examined the anatomical and histological characteristics of the genital organs of the female white-lipped peccary in the wild in different reproductive stages, collected by rural hunters in the North-eastern Peruvian Amazon. Mean ovulation rate was 2.12 +/- 0.83 follicles and litter size was 1.78 +/- 0.41 embryos or fetuses per pregnant female, resulting in a low rate of reproductive wastage, averaging 0.33 +/- 0.66 (16.04%) oocytes or embryos per pregnancy. The ovulation rate and the anatomical performance of the uterus could limit the prolificacy of this species. Females in follicular phase showed follicular waves suggesting the synchronous growth of a cohort of follicles. Different uterine and vaginal epithelium features changed in accordance with the reproductive state of the female. Pregnant females and females in the luteal phase presented a significant proliferation of endometrial uterine glands, characterized by hyperplasia and branching of endometrial glands, and increase in the proportion of cervical epithelial cells with periodic acid-schiff (PAS)-positive granules compared with that in females in the follicular phase. Females in the follicular phase showed a more developed vaginal epithelium (in thickness and in layer composition) than females in the luteal phase and pregnant females.