Tayassu Research Articles

Seminal characterization of white-lipped peccary (Tayassu peccary).

White-lipped peccary (Tayassupecari) is a neotropical mammal that plays a fundamental role in maintaining the integrity of tropical forest systems. However, due to hunting and deforestation the species is currently classified as vulnerable. As there are reports of difficulties in captive reproduction, it was proposed to use assisted reproduction techniques for later reintroduction into their natural habitat. Therefore, the objective was to describe the physical, chemical, morphological and functional characteristics of its semen. Sixteen adult male, white-lipped peccary, aged between three and seven years old, distributed in three groups, were used in this study. After physical and chemical retainment, semen was collected by electroejaculation from 16 individuals. It was evaluated by computer analysis (CASA). The mean values recorded were as follows: volume 0.5±0.6ml, pH 7.2±0.3, sperm concentration 967.2±947.3×106 spermatozoon/ml and total motility of 75.4±16.2. The average sperm reactive to the hypo-osmotic test was 85.3%±21.0%, and 62.4%±43.9% of the cells presented intact membranes in the structural integrity test. Additionally, the semen showed milky consistency (80%), yellowish colour (40%) and sui generis odour (100%). The sperm parameters of the white-lipped peccary are within the desirable standards, allowing them to be considered as potentially fertile for the development of assisted reproduction techniques that may contribute to the conservation of the species.

Large herbivore-palm interactions modulate the spatial structure of seedling communities and productivity in Neotropical forests

Top-down control by large herbivores is a well-known driver of plant diversity structure and productivity. Yet, for forest ecosystems the sign and magnitude of herbivore control across resource gradients is not well understood. We conducted a series of replicated large herbivore exclusion experiments in defaunated and non-defaunated Atlantic forests of Brazil to evaluate the effects of large herbivores on tropical plant communities. We hypothesized that the top-down impact of large herbivores on seedling recruitment, species richness, diversity and productivity would change across a natural gradient in the density of a key plant resource, the palm Euterpe edulis, which is thought to act as a foundation species. We found both positive (agonistic) and negative (antagonistic) spatially-structured effects of large herbivores on plant communities driven by an interaction between large herbivores and palm density on non-defaunated sites, but not on defaunated sites. Indeed, through its interaction with large herbivores, palm trees were able to regulate the spatial structure of seedling communities. In the non-defaunated forest, the negative impact of large herbivores on plant recruitment and species richness decreased substantially as palms became more abundant and canopy cover decreased. Furthermore, large herbivores caused a 185% increase but a 194% decrease in aboveground seedling productivity in areas of high and low palm density, respectively. In contrast, in the defaunated forest we did not find any consistent large herbivore impacts on plant recruitment or species richness across the gradient of palm density, and herbivore activity consistently had negative effects on seedling productivity. Analyses using camera trap data indicate that white-lipped peccaries (Tayassu peccari) played a key role in modulating recruitment and seedling productivity, while tapirs (Tapirus terrestris) contributed significantly to an increase in plant diversity, hence playing a functionally complementary role. Our results demonstrate that a key interaction between large forest-dwelling tropical herbivores and their palm resource results in landscape-scale modulation of plant communities through positive and negative spatially-structured feedbacks, and support the view that palms might act as foundation species in tropical forests. Anthropogenic pressures posed by defaunation and illegal palm harvesting in the Neotropics might lead to the functional loss of this interaction and the collapse of the spatial structure along palm density gradients, with cascading effects on the dynamics and productivity of tropical forests.

Human disturbance and shifts in vertebratecommunity compositionin a biodiversity hotspot.

Understanding how human modification of the landscape shapes vertebrate community composition is vital to understanding the current status and future trajectory of wildlife. Using a participatory approach, we deployed the largest camera-trap network in Mesoamerica to date to investigate how anthropogenic disturbance shapes the occupancy and co-occurrence of terrestrial vertebrate species in a tropical biodiversity hotspot: the Osa Peninsula, Costa Rica. We estimated species richness in different categories of land protection with rarefaction analysis and estimated the expected occupancy with a joint species distribution model that included covariates for anthropogenic disturbance, land protection, habitat quality, and habitat availability. Areas with the most stringent land-use protections (e.g., Corcovado National Park, 24 species [95% CI 23-25]) harbored significantly more species than unprotected areas (20 species [19.7-20.3]), mainly due to a reduced presence of large-bodied species of conservation concern in unprotected areas (e.g., jaguar Panthera onca and white-lipped peccary Tayassu pecari). Small-bodied generalist species, such as opossums (Didelphidae) and armadillos (Dasypus novemcinctus), in contrast, were more common at disturbed sites, resulting in a significant difference in vertebrate community composition between sites with low and high disturbance. Co-occurrence of species was also mainly associated with response to disturbance. Similar responses to disturbance create two groups of species, those whose site-level occupancy usually increased as anthropogenic disturbance increased and those whose estimated occupancy decreased. The absence of large-bodied species entails an important loss of ecological function in disturbed areas and can hinder forest development and maintenance. Efforts to protect and restore forested landscapes are likely having a positive effect on the abundance of some threatened species. These efforts, however, must be sustained and expanded to increase connectivity and ensure the long-term viability of the wildlife community.

Use of mineral licks by mammals in areas of the Amazonia with no hunting pressure

Mineral licks are areas where several species of animals, including mammals, converge to consume water and soil as a mineral supplement. Certain mammal species are an important source of protein in the diet of indigenous communities. Many of these species are under hunting pressure and their populations have been seriously affected. The purpose of this study was to determine the species of large and medium-sized mammals that use three open mineral licks in the area of the Kichwa Añangu community, within the Yasuní National Park, where hunting used to take place. We calculate the capture frequency for the visiting species and the richness, composition, and similarity of the assemblages recorded in the mineral licks during two climatic seasons of the year (higher rainfall vs. lower rainfall). We installed a single camera trap station (CTS) at each mineral lick during three sampling periods in 2018. In each period, all cameras operated 24 hours a day for 30 to 40 days and were set to capture three photographs upon sensor activation, with 60-second intervals between consecutive activations. With a total sampling effort of 249 days/trap, we obtained 645 photographs and 398 grouped records of 16 species. We recorded 95.2 % of the expected richness according to the Chao1 estimator (S = 16.8). The species with the highest capture frequency were: Mazama zamora (FC = 62.2), Tayassu pecari (FC = 35.7), Tapirus terrestris (FC = 28.9), and Pecari tajacu (FC = 8.0). ECT-1 and ECT-2 captured 11 species each, and ECT-3 captured nine species. There were no significant differences in the species composition between the three mineral licks or between climatic seasons. Our results show that the focal mineral licks studied attract a rich mammalian fauna, which likely points to the success of the government regulation of wildlife trafficking and the application of sustainable tourism practices in the Añangu community.

Dominance hierarchy and social network in a captive group of white-lipped peccary males: what happens after the alpha male leaves?

Dominance hierarchy and social network in a captive group of white-lipped peccary males: what happens after the alpha male leaves?

Third-party conflict interventions are kin biased in captive white-lipped peccaries (Mammalia, Tayassuidae)

Third-party interventions may regulate conflicts to reduce aggression and promote cohesion amongst group members, but are rarely documented in ungulates. The white-lipped peccary (Tayassu pecari) lives in mixed-sex herds of hundreds of individuals in Neotropical forests, which are likely to benefit from mechanisms that sustain social cohesiveness. We examined third-party conflict interventions between individuals in captive groups of white-lipped peccaries. During a period of 60 days, we recorded agonistic interactions and occurrences of third-party conflict interventions, and estimated the genetic relatedness between the individuals involved using multilocus microsatellite genotypes. Most third-party conflict interventions were by the dominant male of each group, resulting in conflict termination 100% of the time. Our results also revealed that white-lipped peccaries favour their closest relatives and that individuals showed lower levels of aggression towards kin than to non-kin, and interventions on behalf of kin were more frequent than on behalf of non-kin. Our findings support the idea that genetic relatedness is fundamental in both social structure and third-party conflict interventions in this species, allowing us to suggest that kin selection could have a key role in the evolution of social behaviour of white-lipped peccaries.

Temperature induces activity reduction in a Neotropical ungulate

AbstractBecause global climate change results in increasingly extreme temperatures and more frequent droughts, behavioral thermoregulation is one avenue by which species may adjust. Changes in activity patterns in response to temperature have been observed in a number of mammal species, but rarely have been investigated in humid tropical habitats. Here we examine the relationship between activity patterns and microclimate temperatures for white-lipped peccaries (Tayassu pecari, Tayassuidae, Cetartiodactyla) in four distinct biomes—the Cerrado, the Pantanal, the Atlantic Forest, and the Amazon. From 2013 to 2017, we monitored 30 white-lipped peccaries fitted with GPS collars that included accelerometers and temperature sensors. White-lipped peccaries were primarily diurnal, with peaks of activity in the morning and late afternoon, except in the Amazon where activity was high throughout the day. Total time active did not vary seasonally. White-lipped peccaries were significantly less likely to be active as temperatures increased, with the probability of being active decreasing by >49% in all biomes between 30 and 40°C. Our findings indicate that white-lipped peccaries are likely to be adversely impacted by rising temperatures, through being forced to reduce foraging time during their prime active periods.

MAMÍFEROS DE MÉDIO E GRANDE PORTE NA ÁREA DE PROTEÇÃO AMBIENTAL MUNICIPAL DO RIO VERMELHO EM SANTA CATARINA, SUL DO BRASIL

MEDIUM AND LARGE MAMMALS IN RIO VERMELHO MUNICIPAL ENVIRONMENTAL PROTECTION AREA, SANTA CATARINA, SOUTHERN BRAZIL: Most studies on medium and large mammals in the Brazilian Atlantic Forest are carried out in areas under full protection (as parks and biological reserves). Considering the continuing threats that the forest remnants are suffering, it is essential to carry out mammal surveys in protected areas for sustainable use. In order to evaluate the species richness and the relative frequency of medium and large mammals in the área de proteção ambiental municipal do Rio Vermelho – APARV (northern Santa Catarina state), methodologies of direct visualization and camera traps were used. The study was conducted from the beginning of 2015 to the end of 2019. In Santa Catarina state, there is only one study which sampling effort is comparable to the present one (7300 night-trap). Thirty-three native mammal species and two alien species (Canis familiaris and Lepus europaeus) were found. The species accumulation curve tended to stabilize at the beginning of the third year. Three species were responsible for more than half of the photographic records (Cerdocyon thous, Eira barbara and Procyon cancrivorus). In total, 33.3% of the species are classified in some category of threat, and three of these species are among the less recorded in Santa Catarina state (Tayassu pecari, Tapirus terrestris and Mazama nana). Our survey added 18 new occurrences to the APARV management plan. Only two of the 18 mammal surveys carried out previously in the Santa Catarina state recorded more species than our study. This is the second survey which was carried out in protected areas for sustainable use in Santa Catarina state. Our study contributes to the important knowledge that can be used in conservation measures. In this way, the APARV plays a fundamental role for the conservation of the Atlantic Forest mammals, constituting an important area favoring the population movements of mammals.

Setting priority conservation management regions to reverse rapid range decline of a key neotropical forest ungulate

Mammals are important components of biodiversity that have been drastically and rapidly impacted by climate change, habitat loss, and anthropogenic pressure. Understanding key species distribution to optimize conservation targets is both urgent and necessary to reverse the current biodiversity crisis. Herein, we applied habitat suitability models for a key Neotropical forest ungulate, the white-lipped peccary (WLP Tayassu pecari), to investigate the effects of climate and landscape modifications on its distribution, which has been drastically reduced in Brazil. We used 318 primary records of WLP to derive habitat suitability maps across Brazil. Our models included bioclimatic, topographic, landscape, and human influence predictors in two modelling approaches. Models including all categories of predictors obtained the highest predictive ability and showed prevalence of suitable areas in forested regions of the country, covering 49% of the Brazilian territory. Filtering out small forest fragments (<2050 ha) reduced the suitable area by 5%, with a further reduction of 4% that was caused by deforestation until 2020, therefore until 2020, the species has suffered a reduction of ~60% from its historical range in Brazil. Of the 40% of the Brazilian territory suitable to WLP, only 12% is protected. In the Atlantic Forest, only half of all protected areas have suitable habitat for WLP and even less in Pantanal (44%), Cerrado (14%) and Caatinga (7%). In a second modelling approach, mapping the areas with suitable climate and those with suitable landscapes separately, allowed us to identify four categories of conservation values, and showed that only 17% of the Brazilian territory has both high landscape and climatic suitability for WLP. Our models can help inform complementary conservation management strategies and actions that could be essential in slowing down and possibly reversing current trends of population and geographic range reductions for the species, thereby averting a possible future collapse of forest ecosystem functioning in the Neotropical region.

Quantifying bite force in coexisting tayassuids and feral suids: a comparison between morphometric functional proxies and in vivo measurements.

BackgroundMeasuring mammals’ bite force in laboratory conditions is not a simple task, let alone on wild medium-sized mammals in the field. Thus, morphometric-proxies are usually used to infer morphofunctional properties of musculoskeletal features. For instance, the study of bite force-indexes suggests that different capacities to crack food items reduce the competition between coexistent collared and white-lipped peccaries (Pecari tajacu and Tayassu pecari). The presence of exotic feral hogs (Sus scrofa) in peccaries’ endemic areas gives rise to new ecological interactions between them. An example is the Brazilian Pantanal wetland, where ecomorphological mechanisms may play a role in their ecological relations. Taking this scenario as a case of study, we aimed to verify if the morphometric-proxies are de facto reliable tools, by comparing bite forces-indexes with the in vivo bite forces of these species.MethodsWe captured 21 collared and white-lipped peccaries and feral hogs in the Brazilian Pantanal to assess their bite force at first molar. The Bite Force Measuring Tube (BiTu) is a robust and simple mechanical device designed to be used in field conditions. Only 11 individuals successfully bit the BiTu before being released. Their body measurements were compared and correlated with their bite force. The in vivo bite forces were compared with bite force-indexes of two papers based on independent morphometric methods and datasets: Sicuro & Oliveira (2002) used classic morphometrics to infer the bite forces of these three species in the Brazilian Pantanal, and Hendges et al. (2019) used geometric morphometrics to compare bite forces-indexes and feeding habits of the extant peccary species. The results of all species were standardized (Z-curves) according to each method. Doing so, we obtained comparable dimensionless comparable values but maintaining the differences between them.ResultsThe morphometric-proxies-based studies presented similar results: collared peccaries present weaker bites than white-lipped peccaries and feral hogs, while these two species presented no significant differences in their bite force-indexes. The in vivo bite force results suggest the same relations predicted by the morphometric models, including the high variation among the feral hogs. We found a significant correlation between the individuals’ weight (kg) and their actual bite force (N) but no significant correlations with the head length.ConclusionsThe BiTu proved to be a functional and low-cost tool to measure bite force in field conditions. The in vivo results presented a good correspondence with the predictions based on morphometric-proxies by Sicuro & Oliveira (2002) and Hendges et al. (2019). The results denote that these studies succeed in capturing the biomechanical signal of the three species’ skull-jaw systems. This empirical validation confirms that these morphometric-proxies analyses are reliable methods to ecomorphological and evolutionary inferences.

Ecological corridors in Costa Rica: An evaluation applying landscape structure, fragmentation‐connectivity process, and climate adaptation

AbstractIn recent years, ecological corridors have been proposed on a global scale as a response to the accelerated process of natural ecosystem fragmentation, mainly as a result of human impact. In accordance with this trend, Costa Rica has undergone a process of implementing ecological corridors as to promote ecological connectivity since the 1990s, with the establishment of 44 ecological corridors covering 38% of Costa Rica's territory. Nevertheless, there is no research evaluating these corridors on a national scale that takes into account their functions as conduits, barriers, and habitats. Thus, the objective of this research was to describe the process of biological corridor formation in Costa Rica, and to evaluate the potential effectiveness of corridors by considering aspects of landscape structure and ecological processes related to connectivity and fragmentation. We used the National Program of Ecological Corridors database along with coverage analysis from Landsat images from 2000 and 2015.The composition of the biological corridors was determined at the landscape scale and related to potential to maintain a specific population of wild mammals weighing more than 10 kg. The composition of the ecological corridors was highly variable in terms of total area, proportion of natural habitat, and fragmentation process. Most biological corridors are capable of maintaining viable populations of Pecari tajacu and Tapir bairdii, while none could maintain populations of Panthera onca and Tayassu pecari. Only 50% of the biological corridors had improved in their connectivity. Therefore, public policies, such as master plans focusing on ecosystem restoration must be established. In addition, only two biological corridors incorporate the majority of elevation ranges (Life Zones) present in the country, which reduces the potential of the corridor system as a tool for climate change adaptation.

Using Data Mining and Network Analysis to Infer Arboviral Dynamics: The Case of Mosquito-Borne Flaviviruses Reported in Mexico.

Simple SummaryGiven the significant impact on both human and animal health of mosquito-borne flaviviruses, a better understanding of their transmission cycles, viewed as a complex multi pathogen-vector-host system is urgently required. Here, we use a spatial datamining framework, based on co-occurrence data that includes biotic niche variables to create models for Dengue, Yellow fever, West Nile Virus and St. Louis encephalitis in Mexico that predict: (i) which mosquito species are likely to be the most important vectors for a given pathogen; (ii) which species are most likely to be important from a multi-pathogenic viewpoint; and (iii) which mosquito and/or mammal assemblages are most likely to play an important role in the transmission cycles. Our predictions are consistent with known information about the dynamics of these mosquito-borne flaviviruses and predict new potential vectors. Our approach can improve disease surveillance efforts and generate useful information regarding public health and biodiversity conservation.Given the significant impact of mosquito-borne flaviviruses (MBFVs) on both human and animal health, predicting their dynamics and understanding their transmission cycle is of the utmost importance. Usually, predictions about the distribution of priority pathogens, such as Dengue, Yellow fever, West Nile Virus and St. Louis encephalitis, relate abiotic elements to simple biotic components, such as a single causal agent. Furthermore, focusing on single pathogens neglects the possibility of interactions and the existence of common elements in the transmission cycles of multiple pathogens. A necessary, but not sufficient, condition that a mosquito be a vector of a MBFV is that it co-occurs with hosts of the pathogen. We therefore use a recently developed modeling framework, based on co-occurrence data, to infer potential biotic interactions between those mosquito and mammal species which have previously been identified as vectors or confirmed positives of at least one of the considered MBFVs. We thus create models for predicting the relative importance of mosquito species as potential vectors for each pathogen, and also for all pathogens together, using the known vectors to validate the models. We infer that various mosquito species are likely to be significant vectors, even though they have not currently been identified as such, and are likely to harbor multiple pathogens, again validating the predictions with known results. Besides the above “niche-based” viewpoint we also consider an assemblage-based analysis, wherein we use a community-identification algorithm to identify those mosquito and/or mammal species that form assemblages by dint of their significant degree of co-occurrence. The most cohesive assemblage includes important primary vectors, such as A. aegypti, A. albopictus, C. quinquefasciatus, C. pipiens and mammals with abundant populations that are well-adapted to human environments, such as the white-tailed deer (Odocoileus virginianus), peccary (Tayassu pecari), opossum (Didelphis marsupialis) and bats (Artibeus lituratus and Sturnira lilium). Our results suggest that this assemblage has an important role in the transmission dynamics of this viral group viewed as a complex multi-pathogen-vector-host system. By including biotic risk factors our approach also modifies the geographical risk profiles of the spatial distribution of MBFVs in Mexico relative to a consideration of only abiotic niche variables.

On the Supposed Presence of Miocene Tayassuidae and Dromomerycinae (Mammalia, Cetartiodactyla) in South America

The earliest record of North American mammals in South America is significant for constraining the timing of intercontinental faunal interchange. At present, the oldest securely dated remains of a North American terrestrial mammal in South America pertain to a late Miocene procyonid; a few other North American mammal groups are present in late Miocene and early Pliocene outcrops in South America, but most are not recorded until the late Pliocene or Pleistocene, after the complete emergence of the Panamanian Isthmus. This long-established pattern has recently been called into question by reports of a proboscidean, two tayassuids, and a dromomerycine cervoid in supposed late Miocene deposits of Peruvian Amazon. In this contribution, we analyze the taxonomic identities and stratigraphic provenances of the tayassuid and dromomerycine fossils in detail. We conclude that these specimens are not distinguishable from modern tayassuids (Tayassu pecari and Dicotyles tajacu) and cervids, and that previous taxonomic identifications are based on misinterpretation of characters or inadequate specimens. In addition, there is insufficient evidence to support a late Miocene age for these terrestrial cetartiodactyl fossils; the stratigraphic provenance of the specimens is highly dubious, and the fossils are likely Quaternary in age.

Comparative chromosome painting in Chacoan peccary, Catagonus wagneri.

Chacoan peccary (Catagonus wagneri, 2n=20) is the most endangered of three extant species of Tayassuidae. Its karyotype has been studied only by differential chromosome staining methods so far. To establish a comparative cytogenetic map of the peccary, we used cross-species hybridization with porcine (Sus scrofa, 2n=38) painting probes. Painting revealed 30 evolutionary conserved autosomal segments between pig and peccary. The q-arm of the submetacentric chromosome X is homologous to the porcine X chromosome, while the p-arm is composed of heterochromatin. Nucleolar organizer regions were detected on chromosomes 8 and 9 which are homologous to pig chromosomes 8 and 4/18, respectively. Fusions of chromosomes homologous to pig chromosomes 4/7 and 4/18 and fission of chromosome 7 are synapomorphic characters shared by Catagonus wagneri and Tayassu pecari but not by Pecari tajacu. Our results confirmed a high rate of karyotype evolution in Tayassuidae and a closer relationship of Catagonus wagneri with Tayassu pecari than with Pecari tajacu.

Comparison of big cat food habits in the Amazon piedmont forest in two Bolivian protected areas

The feeding habits of jaguar (Panthera onca) and puma (Puma concolor) were studied in the lower Tuichi, Hondo (PNANMI Madidi) and Quiquibey (RB Pilón Lajas) river valleys. A total of 122 large felid scats were collected and identified by an experienced local guide, with identifications later confirmed by morphometry. Of this total, 54 were also identified using associated tracks. For jaguar, prey species richness was 25 species considering all scats and 20 species only considering those scats associated with tracks. For puma, 28 and 22 prey species were obtained, respectively. The results indicate that there is low trophic niche overlap between both cats (0.46 and 0.44 respectively). The breadth of the trophic niche indicates that the jaguar is more specialized in its diet (0.28 and 0.42 respectively), mainly due to the high consumption of the white-lipped peccary (Tayassu pecari), which contributes significantly to jaguar prey biomass. The puma has a more generalist tendency (0.56 and 0.58 respectively), with the spotted paca (Cuniculus paca) the most frequently consumed prey and also contributing the most biomass. Despite the fact that both felines share most of their prey, jaguar and puma differ in the frequency of prey consumption.

Chemical Restraining and Electroejaculation Protocols for Semen Collection in White-Lipped Peccary (Tayassu pecari)

Background: In order to reverse the White-lipped peccary decline, besides protecting its habitat and controlling hunting, it is necessary a captive breeding program. There are reports, however, on the low fertility of white-lipped peccary, making it difficult its reproduction in captivity, making artificial insemination one of the main tools to prevent the loss of genetic diversity of species kept in captivity. Information on safe methods of anesthesia and the collection of semen should be investigated. Therefore, we aimed to compare the effects of the anesthetic protocols acepromazine/ketamine and xylazine/ketamine, as well as electroejaculation protocols, for semen collection in white-lipped peccary (Tayassu pecari).Materials, Methods &amp; Results: Twelve adult male white-lipped peccaries were submitted both to the xylazine/ketamine and acepromazine/ketamine anesthetic protocols. The anesthetic induction time and duration, the degree of muscle relaxation, the time for anesthetic recovery and the quality of the animals’ recovery were evaluated. Additionally, the quality of the sedation was evaluated based on the animal’s behavior. We also evaluated the effect of drugs on erectile functions as well as the efficiency of three electroejaculation protocols with increasing or fixed voltages (2 to 4 V; 5 to 12 V; 12 V). The acepromazine/ketamine combination promotes shorter induction time, duration and recovery from anesthesia than the xylazine/ketamine association. There were no differences, however, between the tested anesthetic protocols in relation to heart rate, respiratory rate and temperature. Ejaculate was obtained from only 2 animals when using the xylazine/ketamine protocol and adoption of stimuli between 5 and 12 V, with 10 stimuli at each voltage. In turn, ejaculate was obtained from four animals submitted to the acepromazine/ketamine protocol, three of them with the adoption of stimuli between 5 and 12 V and one with the adoption of fixed 12 V stimuli, with 45 stimuli at this single voltage.Discussion: The animals presented less deep anesthesia and, consequently, worse indicators of well-being during and after the collection procedures when submitted to the xylazine/ketamine protocol compared to the acepromazine/ketamine protocol. When submitted to the acepromazine/ketamine protocol, the animals allowed the observer to approach and handle them, facilitating handling and collection of semen, in addition to promoting better indicators of animal welfare. Also, with this aforementioned protocol, the animals showed better anesthetic return. For both anesthetic protocols, the protocol of increasing stimuli from 5 to 12 V, with 10 stimuli at each voltage, resulted in penile erection and in obtaining ejaculate in a greater number of animals in relation to the other electroejaculation protocols. In turn, the use of the growing protocol 2 V to 4 V did not even cause an erection in any of the 12 animals. From the ejaculates collected from the white-lipped peccary, volumes (0.2 to 1.0 mL) and average sperm concentration (379.1 x 106 sperm/mL) were comparatively higher than those from Pecari tajacu. The white-lipped peccary (Tayassu pecari) is considered an aggressive animal, and this characteristic can explain the relatively low success in obtaining ejaculates, as aggressiveness is directly related to stress, which is an antagonist of ejaculation. Thus, we proposed to test chemical restraint with the aid of a blowgun in future studies.

Using noninvasive techniques to monitor game species targeted by poaching in Misiones, Argentina

ABSTRACT Misiones, Argentina contains the largest remnant of Upper Paraná Atlantic forest; however, half of it is unprotected. The long-term survival of its biodiversity is threatened by poaching and habitat loss, which eliminate animal populations and decrease genetic variability in species. Noninvasive techniques were used to evaluate the presence of four mammals [white-lipped peccary (Tayassu pecari), collared peccary (Pecari tajacu), tapir (Tapirus terrestris), and paca (Cuniculus paca)] often targeted by poachers. With detection dogs, 179 scats were collected across intact and modified habitats in the northern-central zones of Misiones. Of the samples collected, 76.5% (n = 137) could be genetically confirmed as one of the three targeted prey: 98 white-lipped peccaries, 13 collared peccaries, and 26 tapirs. A greater proportion of white-lipped peccary and collared peccary samples were associated with heterogeneous landscapes (74.5% and 76.9%, respectively), which contrasts with tapirs that had a higher proportion (76.9%) in native forest. While collared peccaries and tapirs had close association with protected areas (84.6% and 96.2%, respectively), over half (57.1%) of the white-lipped peccary samples were located outside of protected areas. Despite a higher proportion of survey coverage in the central zone (64.0%), the majority (81.8%) of prey samples were in the northern zone. While samples were found across habitats that varied in integrity and degree of protection, the restrictions seen among prey species distributions indicate concern for their long-term survival if the threats imposed by poaching, habitat loss, and human expansion are not controlled, especially in the central zone of Misiones.

Large herbivores regulate the spatial recruitment of a hyperdominant Neotropical palm

AbstractLarge mammalian herbivores play an important role in shaping the diversity of tropical forests by affecting the survival of seedlings and saplings beneath parent plants. The white‐lipped peccary (Tayassu pecari) accounts for the largest herbivore biomass that controls seed and seedling survival in Neotropical ecosystems. However, hunting and habitat loss has driven peccaries to local extinction for most of their original distribution, so it is likely that their absence will affect plant recruitment dynamics. We tested the effects of peccary local extinction on the density and spatial distribution of the hyperdominant palm Euterpe edulis by performing a fine‐scale characterization of its spatial recruitment in six forest sites in the Brazilian Atlantic forest. We compared the age structure and the spatial patterns of seedlings, saplings, and adults as well as the relationship between them. We found that while under the presence of peccaries there was a decrease in recruitment rates under adults, the local extinction of these large mammals led to a more clumped process of spatial recruitment. Despite such contrasting spatial patterns of recruitment dynamics, neither age structure nor the random spatial distribution of adults was affected by the presence or absence of peccaries, indicating that their early effects on these palm populations are mitigated as recruitment advances. Our findings highlight the role of large‐bodied forest‐dwelling herbivores in regulating the fine‐scale spatial recruitment of plants and advance our understanding on the effects of defaunation in tropical forests.Abstract in Portuguese is available with online material.

Novos Registros do Queixada (Tayassu pecari Link, 1795) para o Sul do Brasil

O queixada (Tayassu pecari Link, 1795) é uma espécie da família Tayassuidae que ocorre na região neotropical, vivendo em grandes varas. A espécie agora é considerada criticamente ameaçada na Mata Atlântica. Neste trabalho, apresentamos novos registros de T. pecari para o sul do Brasil, feitos no rio Pelotas e no Parque Estadual do Turvo, onde a espécie era tida como extinta. Os novos registros feitos neste parque provavelmente se devem a uma recolonização a partir das florestas de Misiones (Argentina), mas essa conexão está ameaçada pela inundação prevista pelo projeto hidroelétrico Panambi.

Permeability of Neotropical agricultural lands to a key native ungulate—Are well‐connected forests important?

AbstractMuch of what remains of the Earth's tropical forests is embedded within agricultural landscapes, where forest is reduced and fragmented. As native forest ungulates are critical to maintaining forest function, it is imperative to understand how this functional group responds to declines in forest cover and connectivity resulting from agricultural expansion. We addressed this issue by evaluating selection of forest cover and forest connectivity by a key native ungulate of Neotropical forests, the white‐lipped peccary (Tayassu pecari Link 1795, Tayassuidae, Cetartiodactyla), in agricultural landscapes of Brazil. We evaluated selection using compositional analysis at two hierarchical levels, landscape, and home range. From 2013 to 2019, we GPS‐tracked eight white‐lipped peccary herds in Southwest Brazil, resulting in a total of 14,460 GPS locations. We found that herds can live in landscapes with a wide range of forest cover (35%–81% of home ranges covered by native forest), with significant, but not strong, selection at the landscape level (p = .045). Nevertheless, herds strongly select for forest cover within their home ranges (81%–97% of locations within native forest; highly significant selection at the home‐range level: p = .008). As for connectivity, herds significantly select the largest, most connected forest fragments at the landscape level (p = .04), but not at the home‐range level (p = .07). Our results support that Neotropical forests within agricultural landscapes need to be well connected in order to preserve this key native ungulate and maintain long‐term forest function.Abstract in Portuguese is available with online material.