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1.
Ecol Lett ; 25(5): 1152-1163, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35175672

RESUMO

Disease outbreaks induced by humans increasingly threaten wildlife communities worldwide. Like predators, pathogens can be key top-down forces in ecosystems, initiating trophic cascades that may alter food webs. An outbreak of mange in a remote Andean protected area caused a dramatic population decline in a mammalian herbivore (the vicuña), creating conditions to test the cascading effects of disease on the ecological community. By comparing a suite of ecological measurements to pre-disease baseline records, we demonstrate that mange restructured tightly linked trophic interactions previously driven by a mammalian predator (the puma). Following the mange outbreak, scavenger (Andean condor) occurrence in the ecosystem declined sharply and plant biomass and cover increased dramatically in predation refuges where herbivory was historically concentrated. The evidence shows that a disease-induced trophic cascade, mediated by vicuña density, could supplant the predator-induced trophic cascade, mediated by vicuña behaviour, thereby transforming the Andean ecosystem.


Assuntos
Ecossistema , Infestações por Ácaros , Animais , Surtos de Doenças/veterinária , Cadeia Alimentar , Humanos , Mamíferos , Comportamento Predatório
2.
Parasitology ; : 1-6, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-35260216

RESUMO

Sarcoptic mange is a disease caused by an infectious parasite in the vicuñas (Vicugna vicugna) from South America. Although molecular studies have provided much information about the epidemiology of this disease, this information is still unknown in vicuñas. This study determined the prevalence and molecular characterization of Sarcoptes scabiei from vicuñas from Southern Peruvian Andes. During the 2018 shearing season, 181 vicuñas were clinically evaluated for lesions compatible with mange. Sarcoptes scabiei was detected in 35 (19.3%) vicuñas, and 50 mites from 25 vicuñas were selected for molecular analyses of the mitochondrial (cox1) and nuclear (ITS2) genetic markers. Molecular analyses of the cox1 and ITS2 sequences showed an identity of 94­99% and 99.8­100% with previous S. scabiei sequences registered in the GenBank, respectively. Sequence polymorphisms were more evident in the ITS2 than in the cox1, but only the cox1 had an association with the host. Phylogenetic analysis of S. scabiei cox1 sequences from vicuñas showed a cluster with S. scabiei cox1 sequences from canids, suggesting that the origin of S. scabiei from vicuña is associated with canid mites. This research is the first molecular analysis of S. scabiei from vicuñas. Future molecular studies will be necessary to determine the species variety, geographic segregation and host­parasite adaptation for this vicuña's mite.

3.
Gen Comp Endocrinol ; 286: 113299, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606464

RESUMO

State-dependent foraging theory posits that animals should make foraging decisions based on energetic condition, where animals with fewer energetic reserves prioritize foraging over other behaviors, including antipredator behaviors. However, few studies have investigated these trade-offs at an individual level in wild, free-ranging animals. We investigated the relationships between internal condition and behavior in a wild mammal, the vicuña (Vicugna vicugna), which makes state-dependent decisions about the use of two habitats with different characteristics that contribute to their internal condition. Using non-invasively collected fecal samples, we measured glucocorticoid metabolites (GCMs) and thyroid hormones (THs) as indicators of combined stress (predation and nutritional), and just nutritional stress, respectively. We video recorded 20-minute behavioral observations and focused on behaviors which often demand a trade-off between energy acquisition and antipredator behaviors-vigilance and foraging. We found differences in expression of these behaviors between the two sites but found no relationships between physiological parameters (GCMs and THs) and behavior (vigilance and foraging) at either site. We suggest that state-dependent foraging may be difficult to observe in large mammals under baseline conditions and that GCMs and THs may be insensitive to small changes in stress stimuli at this scale, and where these wild animals have the entire suite of behavioral responses available to them.


Assuntos
Glucocorticoides/metabolismo , Comportamento Predatório/efeitos dos fármacos , Tri-Iodotironina/metabolismo , Animais , Camelídeos Americanos
4.
Oecologia ; 189(4): 883-890, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30868375

RESUMO

The landscape of fear is an important driver of prey space use. However, prey can navigate the landscape of fear by exploiting temporal refuges from predation risk. We hypothesized that diel patterns of predator and prey movement and space use would be inversely correlated due to temporal constraints on predator habitat domain. Specifically, we evaluated habitat selection and activity of the vicuña and its only predator, the puma, during three diel periods: day, dawn/dusk, and night. Pumas selected the same habitats regardless of diel period-vegetated and rugged areas that feature stalking cover for pumas-but increased their activity levels during dawn/dusk and night when they benefit from reduced detection by prey. Vicuñas avoided areas selected by pumas and reduced activity at night, but selected vegetated areas and increased activity by day and dawn/dusk. Vicuña habitat selection and movement strategies appeared to reduce the risk of encountering pumas; movement rates of pumas and vicuñas were negatively correlated across the diel cycle, and habitat selection was negatively correlated during dawn/dusk and night. Our study shows that an ambush predator's temporal activity and space use patterns interact to create diel refugia and shape the antipredator behaviors of its prey. Importantly, it is likely the very nature of ambush predators' static habitat specificity that makes predator activity important to temporally varying perceptions of risk. Prey which depend on risky habitats for foraging appear to mitigate risk by feeding when they can more easily detect predators and when predators are least active.


Assuntos
Puma , Refúgio de Vida Selvagem , Animais , Ecossistema , Medo , Comportamento Predatório
5.
Acta Trop ; 249: 107074, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37956821

RESUMO

Hemotrophic mycoplasmas (hemoplasmas) are epierythrocytic bacteria that infect wild and domestic animals, and can cause anemia in some of them. They are considered emerging and zoonotic pathogens, causing serious health problems in wildlife. Candidatus Mycoplasma haemolamae is the only species of hemoplasma that infects domestic South American camelids (alpacas and llamas), with limited studies in wild camelids. Therefore, the objective of this study was to determine the prevalence of Candidatus M. haemolamae in vicunas (Vicugna vicugna) from the Pampa Galeras National Reserve, located in the Ayacucho region of Peru, using molecular diagnosis. For this, blood samples from 79 vicunas were collected, which were molecularly analyzed by partially amplifying the 16S ribosomal RNA gene of Mycoplasma sp. Fourteen vicunas (17.7 %) were positive for the molecular diagnosis of Mycoplasma sp. All PCR-positive products were sequenced and showed more than 99 % identity with Candidatus M. haemolamae. Statistical analysis showed that tick-infested vicunas had 6.10 odds of presenting Candidatus M. haemolamae compared with tick-free vicunas. Sex and age were not associated with Candidatus M. haemolamae infections. This is the first report of hemoplasmas in vicunas, a wild South American camelid, demonstrating that the pathogen can have both a domestic and a wild life cycle. Future studies are necessary to know the current situation of this pathogen in domestic and wild camelids from other locations in Peru.


Assuntos
Camelídeos Americanos , Mycoplasma , Animais , Camelídeos Americanos/microbiologia , Peru/epidemiologia , Animais Domésticos , Mycoplasma/genética , Animais Selvagens , RNA Ribossômico 16S/genética
6.
Ecology ; 105(3): e4262, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38351587

RESUMO

Large animals could be important drivers of spatial nutrient subsidies when they ingest resources in some habitats and release them in others, even moving nutrients against elevational gradients. In high Andean deserts, vicuñas (Vicugna vicugna) move daily between nutrient-rich wet meadows, where there is abundant water and forage but high risk of predation by pumas (Puma concolor), and nutrient-poor open plains with lower risk of predation. In all habitats, vicuñas defecate and urinate in communal latrines. We investigated how these latrines impacted soil and plant nutrient concentrations across three habitats in the Andean ecosystem (meadows, plains, and canyons) and used stable isotope analysis to explore the source of fecal nutrients in latrines. Latrine soils had higher concentrations of nitrogen, carbon, and other nutrients than did nonlatrine soils across all habitats. These inputs corresponded with an increase in plant quality (lower C:N) at latrine sites in plains and canyons, but not in meadows. Stable isotope mixing models suggest that ~7% of nutrients in plains latrines originated from vegetation in meadows, which is disproportionately higher than the relative proportion of meadow habitat (2.6%) in the study area. In contrast, ~68% of nutrients in meadow latrines appear to originate from plains and canyon vegetation, though these habitats made up nearly 98% of the study area. Vicuña diel movements thus appear to concentrate nutrients in latrines within habitats and to drive cross-habitat nutrient subsidies, with disproportionate transport from low-lying, nutrient-rich meadows to more elevated, nutrient-poor plains. When these results are scaled up to the landscape scale, the amount of nitrogen and phosphorus subsidized in soil at plains latrines was of the same order of magnitude as estimates of annual atmospheric nitrogen and phosphorus deposition for this region (albeit far more localized and patchy). Thus, vicuña-mediated nutrient redistribution and deposition appears to be an important process impacting ecosystem functioning in arid Andean environments, on par with other major inputs of nutrients to the system.


Assuntos
Camelídeos Americanos , Animais , Ecossistema , Nitrogênio , Nutrientes , Fósforo , Solo , Isótopos
7.
Sustain Sci ; 17(3): 707-724, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33133295

RESUMO

South American Camelids (SACs) make several material and non-material contributions to people and are a key component of the Andean biocultural heritage. From the perspective of the IPBES' Conceptual Framework, SACs constitute the "nature" component in the complex system of interactions between human societies and the Andean mountain environment. There are four SAC living species today, two of which are wild, or Salqa, in the indigenous cosmovision: guanaco (Lama guanicoe) and vicuña (Vicugna vicugna). Llama (Lama glama) and alpaca (Vicugna pacos) were domesticated 5000 years ago, and are therefore Uywa, in the indigenous cosmovision. Both wild and domestic camelids were, and in several cases still are, the most highly appreciated resource for Andean livelihoods. Historically, camelids and their contributions have been used by Andean people since the peopling of the Americas over 11,000 years ago. In this paper, we present three case studies (chakus for vicuña management, llama caravans, and llama nanobodies) to bring attention to the essential role of vicuñas and llamas for Andean communities today, their intercultural linkages with the Western world, and telecoupling interactions.

8.
Ecology ; 101(12): e03172, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32852062

RESUMO

Predator-prey games emerge when predators and prey dynamically respond to the behavior of one another, driving the outcomes of predator-prey interactions. Predation success is a function of the combined probabilities of encountering and capturing prey, which are influenced by both prey behavior and environmental features. While the relative importance of encounter and capture probabilities have been evaluated in a spatial framework, temporal variation in prey behavior and intrinsic catchability are likely to also affect the distribution of predation events. Using a single-predator-single-prey (puma-vicuña) system, we evaluated which factors predict predation events across both temporal and spatial dimensions of the components of predation by testing the prey-abundance hypothesis (predators select for high encounter probability) and the prey-catchability hypothesis (predators select for high relative capture probability) in time and space. We found that for both temporal and spatial analyses, neither the prey-abundance hypothesis nor the prey-catchability hypothesis alone predicted kill frequency or distribution; puma kill frequency was static throughout the diel cycle and pumas consistently selected a single habitat type when hunting, despite temporal and spatial variation in encounter rates and intrinsic catchability. Our integrated spatiotemporal analysis revealed that an interaction between time of day and habitat influences kill probability, suggesting that trade-offs in the temporal and spatial components of predation drive the probability of predation events. These findings reinforce the importance of examining both the temporal and spatial patterns of the components of predation, rather than unidimensional measures of predator or prey behavior, to comprehensively describe the feedbacks between predator and prey in the predator-prey game.


Assuntos
Carnívoros , Comportamento Predatório , Animais , Ecossistema , Análise Espaço-Temporal
9.
Ecology ; 100(7): e02724, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31157915

RESUMO

The spatial relationship between predator and prey is often conceptualized as a behavioral response race, in which prey avoid predators while predators track prey. Limiting habitat types can create spatial anchors for prey or predators, influencing the likelihood that the predator or prey response will dominate. Joint spatial anchors emerge when predator and prey occupy similar feeding habitat domains and risk and reward become spatially conflated, confusing predictions of which player will win the space race. These spatial dynamics of risk-foraging trade-offs are often obscured by habitat heterogeneity and community complexity in large vertebrate systems, fueling ambiguity regarding the generality of predictions from predator-prey theory. To test how habitat distribution influences the predator-prey space race, we examine correlation in puma and vicuña habitat selection and space use at two sites, one of which generates a distinct risk-foraging trade-off at a joint spatial anchor. The distribution of vegetation, which serves as both forage for vicuñas and stalking cover for pumas, differs between the sites; the llano contains a single central meadow that acts as a joint spatial anchor, while the canyon is characterized by more heterogeneous vegetation. Puma-vicuña habitat selection correlation was positive in the llano and negative in the canyon, and similarly, utilization distributions were more strongly correlated in the llano than the canyon. Vicuña locations occurred at higher values of puma habitat selection and utilization in the llano than in the canyon. Similarly, puma locations in the llano occurred at higher values of vicuña habitat selection and utilization than in the canyon. Although pumas consistently selected for and utilized vegetative and topographic cover regardless of habitat distribution, vicuñas only selected against vegetation in the heterogeneous canyon site, reducing spatial correlation with pumas. Our work suggests a joint spatial anchor favors pumas in the space race due to the inability for vicuñas to avoid crucial foraging habitat. The outcome of the predator-prey space race appears to be strongly informed by the distribution of habitat, whereby corresponding predictability of predator and prey favors predators in the spatial game.


Assuntos
Comportamento Predatório , Puma , Animais , Ecossistema
10.
Vet Parasitol ; 244: 21-24, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28917312

RESUMO

Linguatula serrata, a pentastomid, was found parasitizing the lungs of a vicuña (Vicugna vicugna) from Cuzco, Peru. A total of 13 larvae were found encysted in the parenchymal tissue of the lungs. All larvae were identified as nymphal stages of L. serrata by morphological methods Diagnosis was confirmed by molecular analysis amplifying the cytochrome c oxidase 1 gene of three nymphs. Nucleotide sequences from the isolates were compared to previous sequences from GenBank, and it showed high similarity between them (>99%). This finding constitutes the first detection of L. serrata in a South American camelid.


Assuntos
Doenças Parasitárias em Animais/diagnóstico , Pentastomídeos/classificação , Animais , Camelídeos Americanos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Larva , Pulmão/parasitologia , Masculino , Ninfa , Doenças Parasitárias em Animais/parasitologia , Pentastomídeos/genética , Peru , Análise de Sequência de DNA/veterinária
11.
Ecology ; 102(2): e03228, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33098659
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