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1.
PLoS One ; 17(10): e0276297, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36264921

RESUMO

Many vertebrate species undergo population fluctuations that may be random or regularly cyclic in nature. Vertebrate population cycles in northern latitudes are driven by both endogenous and exogenous factors. Suggested causes of mysterious disappearances documented for populations of the Neotropical, herd-forming, white-lipped peccary (Tayassu pecari, henceforth "WLP") include large-scale movements, overhunting, extreme floods, or disease outbreaks. By analyzing 43 disappearance events across the Neotropics and 88 years of commercial and subsistence harvest data for the Amazon, we show that WLP disappearances are widespread and occur regularly and at large spatiotemporal scales throughout the species' range. We present evidence that the disappearances represent 7-12-year troughs in 20-30-year WLP population cycles occurring synchronously at regional and perhaps continent-wide spatial scales as large as 10,000-5 million km2. This may represent the first documented case of natural population cyclicity in a Neotropical mammal. Because WLP populations often increase dramatically prior to a disappearance, we posit that their population cycles result from over-compensatory, density-dependent mortality. Our data also suggest that the increase phase of a WLP cycle is partly dependent on recolonization from proximal, unfragmented and undisturbed forests. This highlights the importance of very large, continuous natural areas that enable source-sink population dynamics and ensure re-colonization and local population persistence in time and space.


Assuntos
Artiodáctilos , Animais , Florestas , Mamíferos
2.
Ecology ; 103(9): e3738, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35567292

RESUMO

The Amazon forest has the highest biodiversity on Earth. However, information on Amazonian vertebrate diversity is still deficient and scattered across the published, peer-reviewed, and gray literature and in unpublished raw data. Camera traps are an effective non-invasive method of surveying vertebrates, applicable to different scales of time and space. In this study, we organized and standardized camera trap records from different Amazon regions to compile the most extensive data set of inventories of mammal, bird, and reptile species ever assembled for the area. The complete data set comprises 154,123 records of 317 species (185 birds, 119 mammals, and 13 reptiles) gathered from surveys from the Amazonian portion of eight countries (Brazil, Bolivia, Colombia, Ecuador, French Guiana, Peru, Suriname, and Venezuela). The most frequently recorded species per taxa were: mammals: Cuniculus paca (11,907 records); birds: Pauxi tuberosa (3713 records); and reptiles: Tupinambis teguixin (716 records). The information detailed in this data paper opens up opportunities for new ecological studies at different spatial and temporal scales, allowing for a more accurate evaluation of the effects of habitat loss, fragmentation, climate change, and other human-mediated defaunation processes in one of the most important and threatened tropical environments in the world. The data set is not copyright restricted; please cite this data paper when using its data in publications and we also request that researchers and educators inform us of how they are using these data.


Assuntos
Florestas , Mamíferos , Animais , Biodiversidade , Aves , Brasil , Humanos , Répteis , Vertebrados
4.
Trop Anim Health Prod ; 42(8): 1695-703, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20596776

RESUMO

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.


Assuntos
Artiodáctilos , Leptospira interrogans/imunologia , Leptospirose/epidemiologia , Fatores Etários , Testes de Aglutinação/veterinária , Análise de Variância , Animais , Anticorpos Antibacterianos/sangue , Brasil/epidemiologia , Feminino , Masculino , Prevalência , Fatores Sexuais
5.
Ecology ; 101(11): e03128, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32862433

RESUMO

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data.


Assuntos
Canidae , Carnívoros , Mustelidae , Ursidae , Animais , Ecossistema , Humanos
6.
Ecology ; 100(7): e02663, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31013542

RESUMO

Xenarthrans-anteaters, sloths, and armadillos-have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data.

7.
PLoS One ; 10(11): e0141459, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26536608

RESUMO

Inter-specific competition is considered one of the main selective pressures affecting species distribution and coexistence. Different species vary in the way they forage in order to minimize encounters with their competitors and with their predators. However, it is still poorly known whether and how native species change their foraging behavior in the presence of exotic species, particularly in South America. Here we compare diet overlap of fruits and foraging activity period of two sympatric native ungulates (the white-lipped peccary, Tayassu pecari, and the collared peccary, Pecari tajacu) with the invasive feral pig (Sus scrofa) in the Brazilian Pantanal. We found high diet overlap between white-lipped peccaries and feral pigs, but low overlap between collared peccaries and feral pigs. Furthermore, we found that feral pigs may influence the foraging period of both native peccaries, but in different ways. In the absence of feral pigs, collared peccary activity peaks in the early evening, possibly allowing them to avoid white-lipped peccary activity peaks, which occur in the morning. In the presence of feral pigs, collared peccaries forage mostly in early morning, while white-lipped peccaries forage throughout the day. Our results indicate that collared peccaries may avoid foraging at the same time as white-lipped peccaries. However, they forage during the same periods as feral pigs, with whom they have lower diet overlap. Our study highlights how an exotic species may alter interactions between native species by interfering in their foraging periods.


Assuntos
Artiodáctilos/fisiologia , Dieta , Comportamento Alimentar , Sus scrofa/fisiologia , Animais , Brasil , Feminino , Frutas , Masculino
8.
Acta amaz ; 18(3)1988.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454284

RESUMO

Population densities of six primate species (Saguinus midas, Pithecia pithecia, Cebus apella, Chiropotes satanas, Alouatta seniculus and Ateles paniscus) were estimated in continuous forest and in isolated reserves (one of 100 ha and four of 10 ha). Saguinusdensities in the continuous forest were found to be low, probably due to the lack of edge habitat and second growth favoured by them; Pithecia, Cebus and Ateles populations are also low, possibly because of more widely distributed and/or less abundant food sources than is true for other Amazonian regions, although hunting in the past, particularly of Ateles may also be a contributing factor; and Chiropotes and Alouatta densities were found to be similar to those observed in other areas of Amazonas forests. Ateles and Chiropotes, which occupy ranges on the order of three km2 were excluded from the 100-ka reserve at the time of its isolation. Unfortunately populations were not known prior to isolation of this reserve but during isolation there remained four groups of Saguinus, two Pitheciagroups, one Cebus groups and five Alouatta groups. One Saguinus group disappeared two months later, and one year post-isolation the Cebus group also left the reserve. Single Alouatta groups survive in the isolated 10-ha reserves. Saguinus, present in the four 10-ha reserves following isolation, have disappeared from two of them. One 10-ha reserve retains a group of Pithecia.


Atividades agropecuárias na floresta de terra-firme na Amazônia Central resultam invariavelmente em fragmentos de florestas isoladas. Em 1979, o Fundo de Vida Selvagem (WWF-US) em convênio com o lnstituto Nacional de Pesquisas da Amazônia (INPA- CNPq) deu início ao Projeto "Dinâmica Biológica de Fragmentos Florestais", envolvendo estudos dos efeitos dessa fragmentação em áreas (reservas) de tamanhos diferentes no Distrito Agropecuário da SUFRAMA, Manaus. Seis espécies de primatas ocorrem na área Saguinus midas, Pithecia pithecia, Cebus apella, Chiropotes satanas, Alouatta seniculus e Ateles poniscus. Este estudo descreve densidades populacionais dessas espécies na floresta contínua (três reservas de 100 ha não isoladas), numa reserva isolada de 100 ha e em quatro reservas isoladas de 10 ha. A densidade, de Saguinus e baixa, provavelmente por causa da falta de mata de borda e de mata secundária preferidas pelo gênero; populações de Cebus e Ateles também são baixas, talvez pela distribuição escassa e/ou baixa abundância de alimento em comparação com outras regiões amazônicas, embora a caça no passado, especialmente de Ateles, talvez seja um fator contribuinte; e Chiropotes e Alouattaocorrem em densidades semelhantes às outras regiões de floresta amazônica. Grupos de Ateles e Chiropotes, que ocupam áreas de aproximadamente 3 km2, foram excluídos da reserva de 100 ha no momento de seu isolamento. Infelizmente, populações nessa reserva, antes de seu isolamento, não foram investigadas, mas durante a isolação permaneceram quatro grupos de Saguinus, dois grupos de Pithecia, um grupo de Cebus e cinco grupos de Alouatta. Um grupo de Saguinus desapareceu depois de um mê e o grupo de Cebus abandonou a reserva após um ano. Grupos únicos de Alouatta sobrevliem nas reservas isoladas de 10 ha. Indivíduos de Saguinus, embora presentes nessas reservas logo após isolação, desapareceram de duas delas. Uma reserva de 10 ha mantém ainda um grupo de Pithecia.

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