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1.
PLoS One ; 15(7): e0236895, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735578

RESUMO

Many studies on the coexistence of wildlife with livestock have focused primarily on similar-sized species. Furthermore, many of these studies have used dietary overlap as a measure of potential competition between interacting species and thus lack the important link between dietary overlap and any negative effects on a particular species-a prerequisite for competition. Consequently, the mechanisms that drive interspecific interactions between wildlife and cattle are frequently overlooked. To address this, we used an experimental setup where we leveraged different cattle stocking rates across two seasons to identify the drivers of interspecific interactions (i.e. competition and facilitation) between smaller-bodied oribi antelope and cattle. Using direct foraging observations, we assessed dietary overlap and grass regrowth, and also calculated oribi nutritional intake rates. Ultimately, we found that cattle compete with, and facilitate, smaller-bodied oribi antelope through bottom-up control. Specifically, cattle facilitated oribi during the wet season, irrespective of cattle stocking density, because cattle foraging produced high-quality grass regrowth. In contrast, during the dry season, cattle and oribi did not co-exist in the same areas (i.e. no direct dietary overlap). Despite this, we found that cattle foraging at high densities during the previous wet season reduced the dry season availability of oribi's preferred grass species. To compensate, oribi expanded their dry season diet breadth and included less palatable grass species, ultimately reducing their nutritional intake rates. Thus, cattle competed with oribi through a delayed, across-season habitat modification. We show that differences in body size alone may not be able to offset competitive interactions between cattle and wildlife. Finally, understanding the mechanisms that drive facilitation and competition are key to promoting co-existence between cattle and wildlife.


Assuntos
Antílopes/fisiologia , Comportamento Alimentar , Gado/fisiologia , Animais , Animais Selvagens/fisiologia , Tamanho Corporal , Bovinos , Conservação dos Recursos Naturais , Dieta/veterinária , Ecologia , Ecossistema , Herbivoria/fisiologia , Poaceae , Estações do Ano , África do Sul
2.
PLoS One ; 15(8): e0237274, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32780755

RESUMO

Among the world's large Carnivores, American black bears (Ursus americanus) are the foremost conservation success story. Populations have been expanding across North America because the species is adaptable and tolerant of living near people, and because management agencies in the U.S. and Canada controlled hunting and other human-sources of mortality. As a result, human-black bear conflicts (damage to property, general nuisance, threat to human safety) have dramatically increased in some areas, making it urgently important to develop and deploy a variety of mitigation tools. Previous studies claimed that legal hunting did not directly reduce conflicts, but they did not evaluate whether hunting controlled conflicts via management of population size. Here, we compared temporal patterns of phoned-in complaints about black bears (total ~63,500) in Minnesota, USA, over 4 decades to corresponding bear population estimates: both doubled during the first decade. We also quantified natural bear foods, and found that large year-to-year fluctuations affected numbers of complaints; however, since this variation is due largely to weather, this factor cannot be managed. Complaints fell sharply when the management agency (1) shifted more responsibility for preventing and mitigating conflicts to the public; and (2) increased hunting pressure to reduce the bear population. This population reduction was more extreme than intended, however, and after hunting pressure was curtailed, population regrowth was slower than anticipated; consequently both population size and complaints remained at relatively low levels statewide for 2 decades (although with local hotspots). These long-term data indicated that conflicts can be kept in tolerable bounds by managing population size through hunting; but due to the bluntness of this instrument and deficiencies and uncertainties in monitoring and manipulating populations, it is wiser to maintain a population at a level where conflicts are socially-acceptable than try to reduce it once it is well beyond that point.


Assuntos
Animais Selvagens , Ursidae , Animais , Animais Selvagens/fisiologia , Conservação dos Recursos Naturais , Ecossistema , Feminino , Humanos , Masculino , Minnesota , América do Norte , Densidade Demográfica , Dinâmica Populacional , Ursidae/fisiologia
3.
Proc Natl Acad Sci U S A ; 117(28): 16418-16423, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601195

RESUMO

Toxicants such as organochlorine insecticides, lead ammunition, and veterinary drugs have caused severe wildlife poisoning, pushing the populations of several apex species to the edge of extinction. These prime cases epitomize the serious threat that wildlife poisoning poses to biodiversity. Much of the evidence on population effects of wildlife poisoning rests on assessments conducted at an individual level, from which population-level effects are inferred. Contrastingly, we demonstrate a straightforward relationship between poison-induced individual mortality and population changes in the threatened red kite (Milvus milvus). By linking field data of 1,075 poisoned red kites to changes in occupancy and abundance across 274 sites (10 × 10-km squares) over a 20-y time frame, we show a clear relationship between red kite poisoning and the decline of its breeding population in Spain, including local extinctions. Our results further support the species listing as endangered, after a breeding population decline of 31% to 43% in two decades of this once-abundant raptor. Given that poisoning threatens the global populations of more than 2,600 animal species worldwide, a greater understanding of its population-level effects may aid biodiversity conservation through increased regulatory control of chemical substances. Our results illustrate the great potential of long-term and large-scale on-ground monitoring to assist in this task.


Assuntos
Falconiformes/fisiologia , Inseticidas/toxicidade , Drogas Veterinárias/toxicidade , Animais , Animais Selvagens/classificação , Animais Selvagens/crescimento & desenvolvimento , Animais Selvagens/fisiologia , Biodiversidade , Cruzamento , Conservação dos Recursos Naturais , Poluentes Ambientais/toxicidade , Falconiformes/classificação , Falconiformes/crescimento & desenvolvimento , Feminino , Masculino , Dinâmica Populacional
4.
PLoS One ; 15(5): e0232492, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32413032

RESUMO

Coyotes (Canis latrans) and kit foxes (Vulpes macrotis) are desert canids that share ecological similarities, but have disparate histories with anthropogenic pressure that may influence their responses towards novel stimuli. We used remote cameras to investigate response to novel stimuli for these two species. We predicted that coyotes (heavily pressured species) would be more wary towards novel stimuli on unprotected land (canid harvest activities are permitted) than in protected areas (canid harvest activities are not permitted), whereas kit foxes (less pressured species) would exhibit no difference. We examined differences in the investigative behaviors at 660 scent stations in both protected and unprotected areas. Coyotes showed no differences between protected and unprotected land and were generally more wary than kit foxes, supporting our prediction. Kit foxes were more investigative on protected land, contrary to our expectations. Our study provides evidence that anthropogenic pressure can alter the behaviors of wildlife species.


Assuntos
Comportamento Animal/fisiologia , Coiotes/fisiologia , Raposas/fisiologia , Animais , Animais Selvagens/fisiologia , Clima Desértico , Espécies em Perigo de Extinção , Comportamento Exploratório/fisiologia , Odorantes , Feromônios/fisiologia , Fotografação , Tecnologia de Sensoriamento Remoto , Especificidade da Espécie , Utah
5.
PLoS One ; 15(5): e0227317, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32369485

RESUMO

1. Remotely tracking distinct behaviours of animals using acceleration data and machine learning has been carried out successfully in several species in captive settings. In order to study the ecology of animals in natural habitats, such behaviour classification models need to be transferred to wild individuals. However, at present, the development of those models usually requires direct observation of the target animals. 2. The goal of this study was to infer the behaviour of wild, free-roaming animals from acceleration data by training behaviour classification models on captive individuals, without the necessity to observe their wild conspecifics. We further sought to develop methods to validate the credibility of the resulting behaviour extrapolations. 3. We trained two machine learning algorithms proposed by the literature, Random Forest (RF) and Support Vector Machine (SVM), on data from captive red foxes (Vulpes vulpes) and later applied them to data from wild foxes. We also tested a new advance for behaviour classification, by applying a moving window to an Artificial Neural Network (ANN). Finally, we investigated four strategies to validate our classification output. 4. While all three machine learning algorithms performed well under training conditions (Kappa values: RF (0.82), SVM (0.78), ANN (0.85)), the established methods, RF and SVM, failed in classifying distinct behaviours when transferred from captive to wild foxes. Behaviour classification with the ANN and a moving window, in contrast, inferred distinct behaviours and showed consistent results for most individuals. 5. Our approach is a substantial improvement over the methods previously proposed in the literature as it generated plausible results for wild fox behaviour. We were able to infer the behaviour of wild animals that have never been observed in the wild and to further illustrate the credibility of the output. This framework is not restricted to foxes but can be applied to infer the behaviour of many other species and thus empowers new advances in behavioural ecology.


Assuntos
Animais Selvagens/fisiologia , Comportamento Animal/fisiologia , Aprendizado de Máquina , Máquina de Vetores de Suporte , Algoritmos , Animais , Humanos , Redes Neurais de Computação
6.
PLoS One ; 15(4): e0230747, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32236108

RESUMO

Wild turkeys (Meleagris gallopavo; hereafter turkeys) are an important game animal whose popularity among hunters has increased in recent decades. Yet, the number of hunters pursuing turkeys appears to be in flux, patterns of hunter abundance have primarily been described at broad spatial scales, and the ability of management to impact hunter numbers in the post-restoration era of management through opportunity for quality hunting is unclear. We used county-scale estimates of turkey hunter numbers collected over a 14-year period (2001-2014) and time-series analyses to evaluate the spatial scales at which spring and fall turkey hunter populations fluctuate, and also used generalized linear mixed models to evaluate whether attributes related to quality turkey hunting explain recent patterns in hunter abundance. We found heterogeneity in turkey hunter population growth at finer spatial scales than has been previously described (i.e., counties and management units), and provide evidence for spatial structuring of hunter population dynamics among counties that did not always correspond with existing management units. Specifically, the directionality of hunter population change displays spatial structure along an east-west gradient in southern Michigan. We also found little evidence that factors providing opportunity for quality turkey hunting had meaningful impacts on recent spatial-temporal patterns of hunter numbers. Our results imply that providing quality turkey hunting opportunities alone may be insufficient for sustaining populations of turkey hunters in the future, and that modern determinants of hunter participation extend beyond the availability of abundant turkey populations. Moreover, our results demonstrate that interpretation of harvest data as indices of abundance for turkey populations is difficult in the absence of hunter effort data, as changes to turkey harvest are a function of potentially fine-scaled changes in populations of hunters, not simply changes to turkey populations.


Assuntos
Dinâmica Populacional , Perus/crescimento & desenvolvimento , Animais , Animais Selvagens/fisiologia , Humanos , Michigan , Estações do Ano , Esportes , Inquéritos e Questionários
7.
PLoS One ; 15(4): e0231601, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324831

RESUMO

Poland was one of the first countries of Central and Eastern Europe with stable wolf populations to effectively introduce year-round protection of the species. This paper traces the process of policy change using institutional theory as an organizational perspective. Based on the analysis of data from desk research and semi-structured interviews, we propose a model of institutional change and argue that in the 1990s, environmental activists and wildlife biologists successfully used a political window of opportunity connected with socio-economic transformation after 1989 and managed to induce the government to move the species from the domain of hunting to the domain of nature conservation. The new policy, informed by an ecological paradigm, diverged from the historical path dominated by hunters and the vision of the wolf as a pest and a hunting target. The improved protection led to the numerical growth of Poland's wolves and ultimately to their westward expansion.


Assuntos
Animais Selvagens/fisiologia , Governo , Políticas , Lobos/fisiologia , Animais , Geografia , Modelos Teóricos , Polônia
8.
PLoS One ; 15(3): e0230158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32191732

RESUMO

The American White Ibis (Eudocimus albus) is a nomadic wading bird that is increasing the amount of time spent foraging in urban areas, relying on artificial wetlands and other anthropogenic resources year-round. In this study, we explore whether and how American White Ibis association with urban environments is predictive of variation in the timing and length of behavioral seasons. Other urbanized species exhibit altered annual cycles such as loss of migratory behavior and year-round breeding related to consistent resource abundance, often related to intentional and unintentional provisioning. To determine if these same patterns of behavior were also present in White Ibis, we used behavioral change point analysis to segment the tracks of 41 ibis equipped with GPS backpacks to identify the initiation and duration of four behavioral seasons (non-breeding, pre-breeding, breeding, post-breeding) the degree of urban association. We found that intraspecific variation in urban habitat use had strong carryover effects on the timing and duration of behavioral seasons. This study revealed ibis with higher use of urban habitats in non-breeding seasons had longer non-breeding seasons and shorter breeding seasons that began earlier in the year compared to ibis that primarily use wetland habitats. The timing and duration of seasons also varied with ibis age, such that ibis spent more time engaged in breeding-related seasons as they aged. Juvenile and subadult ibis, though considered to be reproductively immature, also exhibit behavioral shifts in relation to breeding seasons. The behavioral patterns found in this study provide evidence that ibis are adapting their annual cycles and seasonal behaviors to exploit urban resources. Future research is needed to identify the effect of interactions between ibis urban association and age on behavioral season expression.


Assuntos
Aves/fisiologia , Ecossistema , Comportamento Alimentar , Urbanização , Migração Animal , Animais , Animais Selvagens/fisiologia , Comportamento , Cruzamento , Reprodução , Estações do Ano , Áreas Alagadas
9.
PLoS One ; 15(2): e0228991, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053691

RESUMO

The need to recognise individuals in population and behavioural studies has stimulated the development of various identification methods. A commonly used method is to employ natural markers to distinguish individuals. In particular, the automated processing of photographs of study animals has gained interest due to the speed of processing and the ability to handle a high volume of records. However, automated processing requires high-quality photographs, which means that they need to be taken from a specific angle or at close distances. Polar bears Ursus maritimus, for example, may be identified by automated analysis of whisker spot patterns. However, to obtain photographs of adequate quality, the animals need to be closer than is usually possible without risk to animal or observer. In this study we tested the accuracy of an alternative method to identify polar bears at further distances. This method is based on distinguishing a set of physiognomic characteristics, which can be recognised from photographs taken in the field at distances of up to 400 m. During five trials, sets of photographs of 15 polar bears from six zoos, with each individual bear portrayed on different dates, were presented for identification to ten test observers. Among observers the repeatability of the assessments was 0.68 (SE 0.011). Observers with previous training in photogrammetric techniques performed better than observers without training. Experience with observing polar bears in the wild did not improve skills to identify individuals on photographs. Among the observers with photogrammetric experience, the rate of erroneous assessment was on average 0.13 (SE 0.020). For the inexperienced group this was 0.72 (SE 0.018). Error rates obtained with automated whisker spot analysis were intermediate (0.26-0.58). We suggest that wildlife studies will benefit from applying several identification techniques to collect data under different conditions.


Assuntos
Comportamento Animal/fisiologia , Animais , Animais Selvagens/fisiologia , Feminino , Masculino , Ursidae
10.
PLoS One ; 15(2): e0229102, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32059022

RESUMO

Hematology, plasma biochemistry, and blood gas analysis were performed on venous samples obtained from free-ranging Eastern Copperheads (Agkistrodon contortrix) and Eastern Ratsnakes (Pantherophis alleghaniensis) in central North Carolina during a mark-recapture study conducted from April to October 2015 at the North Carolina Zoo. Blood samples were collected from 31 (15 male and 16 female) free-ranging copperheads and 34 (20 male and 14 female) free-ranging ratsnakes at the beginning and end of restraint. Restraint was performed for morphometric measurements, sex determination, and identification via placement of intracelomic passive integrated transponder (PIT) tags and marking of ventral scutes with a handheld electrocautery unit. Blood gas analytes were measured at the beginning of restraint and compared to analytes measured at the end to evaluate for changes secondary to handling. Total restraint time prior to the first blood sampling was 1.4 ± 0.4 mins (mean ± SD) and 1.0 ± 0.2 mins (mean ± SD) and restraint time prior to second blood sampling was 12.5 ± 2.4 mins (mean ± SD) and 13.5 ± 3.4 mins (mean ± SD) for copperheads and ratsnakes, respectively. Blood lactate concentrations at the beginning of restraint were similar for both species. Lactate concentrations increased significantly and pH decreased significantly for both species at the end of restraint when compared to the beginning of restraint. Furthermore, lactate concentrations at the end of restraint were significantly elevated in ratsnakes compared to copperheads. This study provides guidelines for interpretation of venous hematology, plasma biochemistry, and blood gas values for free-ranging copperheads and ratsnakes in central North Carolina and demonstrates the physiological response to venous blood gas analytes secondary to capture and restraint.


Assuntos
Agkistrodon/sangue , Animais Selvagens/sangue , Colubridae/sangue , Restrição Física/efeitos adversos , Estresse Fisiológico , Agkistrodon/fisiologia , Animais , Animais Selvagens/fisiologia , Gasometria , Colubridae/fisiologia , Feminino , Concentração de Íons de Hidrogênio , Ácido Láctico/sangue , Masculino , North Carolina , Veias
11.
PLoS One ; 15(2): e0228705, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32032396

RESUMO

Assessing invasive species ecology at multiple scales is needed to understand how to focus ecological monitoring and population control. As a widespread invasive species, wild pigs (Sus scrofa) frequently disrupt land management programs. We provide a detailed, multi-scaled view of the behavior of wild pigs at Fort Hood, Texas, USA by assessing seasonal and daily movement patterns, and diet. First, we quantified movement behavior through assessment of both seasonal home range size and first passage time movement behavior from 16 GPS-collared wild pigs. Home ranges were relatively large (mean: 10.472 km2, SD: 0.472 km2), and Cox proportional hazard models predicted that pigs moved slowest at temperature extremes (15< °C <30), in the spring, in rougher terrain, and in grassland communities. Secondly, we analyzed wild pig stomach contents to determine diet throughout the year. Diet was primarily plant-based, and showed seasonal variation in such items as hard and soft mast, and the foliage of forbs and woody plants. Integration of both movement and diet analyses indicate that wild pigs are more likely to be lured into baited traps in the winter when movement rates are highest and plant-based food resources are likely less abundant. Wild pigs are likely to have the greatest impact on vegetative communities in grassland habitats during the spring season when movement is restricted. Collectively, this multi-scaled approach provided detailed information on wild pig behavioral ecology in this area that would not have been apparent by looking at any single measure individually or only at a large spatial scale (i.e., home range), and could be a useful approach in other invasive species management programs.


Assuntos
Comportamento Animal , Animais , Animais Selvagens/fisiologia , Dieta/veterinária , Ecossistema , Feminino , Masculino , Modelos de Riscos Proporcionais , Estações do Ano , Suínos , Temperatura
12.
PLoS One ; 15(1): e0220482, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31986139

RESUMO

The common long-armed octopus, Octopus minor, is an important component of systems and supports the local fisheries in the coastal areas of northern China. For the fishery management and artificial breeding, especially for the management of exclusive conservation reserves, its role in the ecosystem requires assessment. Therefore, the feeding intensity of O. minor was studied from April to July 2014 when females reaching ovary maturation, and prey composition was identified from stomach contents using a DNA barcoding method. Of the 172 sampled octopuses, 66 had stomach contents that were nearly digested into pulp. On the whole, the feeding intensity of octopus remained more or less the same during the first three months and significantly decreased in July. The changes of feeding intensity were different between females and males; in females, the intensity of feeding decreased from April to July; in case of males, however, the feeding activity increased from April to June and decreased thereafter. The feeding intensity of the females was extremely greater than that of the males. O. minor was a generalist predator and based on homology searches and phylogenetic analysis, a total of 10 different taxa were identified in the stomach contents. In terms of percent composition by frequency of occurrences (%N), fishes accounted for the most of the octopuses diet (50%), followed by cephalopod (25%), crustaceans (21.7%), annelid (1.7%) and nematode (1.7%). The families of Gobiidae and Octopodidae appeared in all months and Protunidae appeared in three months. The results confirmed that Gobiidae family (45.8%, by frequency of occurrences) was an important source of food during the time when females reaching ovarian maturation. From April to July, the observed cannibalism showed an increasing trend. Controlling and reducing fishing production of Gobiidae fishes in conservation area are recommended from April to June when female octopuses are actively feeding.


Assuntos
Animais Selvagens/fisiologia , Ecossistema , Comportamento Alimentar/fisiologia , Octopodiformes/fisiologia , Animais , Crustáceos , Pesqueiros , Conteúdo Gastrointestinal , Perciformes
14.
Sci Adv ; 6(2): eaaw2685, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31934618

RESUMO

Exploration is essential for skill acquisition and strongly facilitates cognitive performance. In humans, it is widely known that exploration and later cognitive performance are highly dependent on early social inputs. Here, we aim to shed light on the evolutionary roots of this process by studying the effects of variation in opportunities for social learning on the exploratory tendency of immature orangutans (Pongo spp.) in nature. We based our analyses on mixed cross-sectional, longitudinal data of exploration by immatures and their mothers. Current exploration rates were correlated with levels of past experienced sociability, but not with current food abundance or with maternal condition, and only partly with genetic similarity. We conclude that the dependence of cognitive development on socially triggered exploration, which underlies the construction of cognitive skills such as intelligence, existed before the emergence of the human lineage.


Assuntos
Animais Selvagens/fisiologia , Comportamento Animal/fisiologia , Comportamento Exploratório/fisiologia , Pongo/fisiologia , Comportamento Social , Animais , Metabolismo Energético , Feminino , Alimentos , Pongo/genética
15.
PLoS One ; 14(12): e0225852, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31790482

RESUMO

Wild bees are important pollinators in many ecosystems threatened by anthropogenic disturbance. Urban development can reduce and degrade natural habitat for bees and other pollinators. However, some researchers suggest that cities could also provide refuge for bees, given that agricultural intensification may pose a greater risk. In this study, we surveyed bee communities at 15 farms and gardens across an urban-rural gradient in southeastern Michigan, USA to evaluate the effect of urbanization on bees. We examined how floral resources, bee functional traits, temperature, farm size, and the spatial scale of analysis influence bee response to urbanization. We found that urbanization positively affected bee diversity and evenness but had no effect on total abundance or species richness. Additionally, urbanization altered bee community composition via differential effects on bee species and functional groups. More urbanized sites supported a greater number of exotic, above-ground nesting, and solitary bees, but fewer eusocial bees. Blooming plant species richness positively influenced bee species diversity and richness. Furthermore, the amount of available floral resources was positively associated with exotic and eusocial bee abundances. Across sites, nearly 70% of floral resources were provided by exotic plants, most of which are characterized as weedy but not invasive. Our study demonstrates that urbanization can benefit some bee species and negatively impact others. Notably, Bombus and Lasioglossum (Dialictus), were two important pollinator groups negatively affected by urbanization. Our study supports the idea that urban environments can provide valuable habitat for diverse bee communities, but demonstrates that some bees are vulnerable to urbanization. Finally, while our results indicate that increasing the abundance and richness of floral resources could partially compensate for negative effects of urbanization on bees, the effectiveness of such measures may be limited by other factors, such as urban warming.


Assuntos
Abelhas/fisiologia , Flores/fisiologia , Característica Quantitativa Herdável , Urbanização , Animais , Animais Selvagens/fisiologia , Especificidade da Espécie , Temperatura
16.
Parasite ; 26: 64, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31697232

RESUMO

Gastro-intestinal nematodes, especially Haemonchus contortus, are widespread pathogenic parasites of small ruminants. Studying their spatial genetic structure is as important as studying host genetic structure to fully understand host-parasite interactions and transmission patterns. For parasites having a simple life cycle (e.g., monoxenous parasites), gene flow and spatial genetic structure are expected to strongly rely on the socio-spatial behavior of their hosts. Based on five microsatellite loci, we tested this hypothesis for H. contortus sampled in a wild Mediterranean mouflon population (Ovis gmelini musimon × Ovis sp.) in which species- and environment-related characteristics have been found to generate socio-spatial units. We nevertheless found that their parasites had no spatial genetic structure, suggesting that mouflon behavior was not enough to limit parasite dispersal in this study area and/or that other ecological and biological factors were involved in this process, for example other hosts, the parasite life cycle, or the study area history.


Assuntos
Comportamento Animal , Haemonchus/genética , Interações Hospedeiro-Parasita , Ovinos/parasitologia , Animais , Animais Selvagens/parasitologia , Animais Selvagens/fisiologia , Meio Ambiente , Feminino , França , Variação Genética , Genética Populacional , Haemonchus/patogenicidade , Estágios do Ciclo de Vida , Masculino , Repetições de Microssatélites , Ovinos/fisiologia
17.
Proc Natl Acad Sci U S A ; 116(47): 23588-23593, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31685619

RESUMO

A major challenge in biology is to understand how phylogeny, diet, and environment shape the mammalian gut microbiome. Yet most studies of nonhuman microbiomes have relied on relatively coarse dietary categorizations and have focused either on individual wild populations or on captive animals that are sheltered from environmental pressures, which may obscure the effects of dietary and environmental variation on microbiome composition in diverse natural communities. We analyzed plant and bacterial DNA in fecal samples from an assemblage of 33 sympatric large-herbivore species (27 native, 6 domesticated) in a semiarid East African savanna, which enabled high-resolution assessment of seasonal variation in both diet and microbiome composition. Phylogenetic relatedness strongly predicted microbiome composition (r = 0.91) and was weakly but significantly correlated with diet composition (r = 0.20). Dietary diversity did not significantly predict microbiome diversity across species or within any species except kudu; however, diet composition was significantly correlated with microbiome composition both across and within most species. We found a spectrum of seasonal sensitivity at the diet-microbiome nexus: Seasonal changes in diet composition explained 25% of seasonal variation in microbiome composition across species. Species' positions on (and deviations from) this spectrum were not obviously driven by phylogeny, body size, digestive strategy, or diet composition; however, domesticated species tended to exhibit greater diet-microbiome turnover than wildlife. Our results reveal marked differences in the influence of environment on the degree of diet-microbiome covariation in free-ranging African megafauna, and this variation is not well explained by canonical predictors of nutritional ecology.


Assuntos
Animais Selvagens/microbiologia , Dieta , Microbioma Gastrointestinal , Mamíferos/microbiologia , Animais , Animais Domésticos/microbiologia , Animais Domésticos/fisiologia , Animais Selvagens/fisiologia , DNA Bacteriano/análise , DNA de Plantas/análise , Fezes/química , Fezes/microbiologia , Herbivoria , Quênia , Mamíferos/fisiologia , Modelos Biológicos , Filogenia , Plantas Comestíveis , Ruminantes/microbiologia , Ruminantes/fisiologia , Estações do Ano , Especificidade da Espécie
18.
Genes (Basel) ; 10(10)2019 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-31635158

RESUMO

Captive breeding has been used as an effective approach to protecting endangered animals but its effect on the gut microbiome and the conservation status of these species is largely unknown. The giant panda is a flagship species for the conservation of wildlife. With integrated efforts including captive breeding, this species has been recently upgraded from "endangered" to "vulnerable" (IUCN 2016). Since a large proportion (21.8%) of their global population is still captive, it is critical to understand how captivity changes the gut microbiome of these pandas and how such alterations to the microbiome might affect their future fitness and potential impact on the ecosystem after release into the wild. Here, we use 16S rRNA (ribosomal RNA) marker gene sequencing and shotgun metagenomics sequencing to demonstrate that the fecal microbiomes differ substantially between wild and captive giant pandas. Fecal microbiome diversity was significantly lower in captive pandas, as was the diversity of functional genes. Additionally, captive pandas have reduced functional potential for cellulose degradation but enriched metabolic pathways for starch metabolism, indicating that they may not adapt to a wild diet after being released into the wild since a major component of their diet in the wild will be bamboo. Most significantly, we observed a significantly higher level of amylase activity but a lower level of cellulase activity in captive giant panda feces than those of wild giant pandas, shown by an in vitro experimental assay. Furthermore, antibiotic resistance genes and virulence factors, as well as heavy metal tolerance genes were enriched in the microbiomes of captive pandas, which raises a great concern of spreading these genes to other wild animals and ecosystems when they are released into a wild environment. Our results clearly show that captivity has altered the giant panda microbiome, which could have unintended negative consequences on their adaptability and the ecosystem during the reintroduction of giant pandas into the wild.


Assuntos
Animais de Zoológico/microbiologia , Microbioma Gastrointestinal , Metagenoma , Ursidae/microbiologia , Amilases/metabolismo , Animais , Animais Selvagens/microbiologia , Animais Selvagens/fisiologia , Animais de Zoológico/fisiologia , Dieta , Farmacorresistência Bacteriana , RNA Ribossômico 16S , Ursidae/fisiologia
19.
PLoS One ; 14(10): e0222627, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644529

RESUMO

The prevalence of social media platforms that share photos and videos could prove useful for wildlife research and conservation programs. When social media users post pictures and videos of animals, near real-time data like individual identification, sex, location, or other information are made accessible to scientists. These data can help inform researchers about animal occurrence, behavior, or threats to survival. The endangered Hawaiian monk seal (Neomonachus schauinslandi) population has only 1,400 seals remaining in the wild. A small but growing population of seals has recently reestablished itself in the human-populated main Hawaiian Islands. While this population growth raises concerns about human-seal interactions it also provides the opportunity to capitalize on human observations to enhance research and conservation activities. We measured the potential utility of non-traditional data sources, in this case Instagram, to supplement current population monitoring of monk seals in the main Hawaiian Islands. We tracked all Instagram posts with the identifier #monkseal for a one-year period and assessed the photos for biological and geographical information, behavioral concerns, human disturbance and public perceptions. Social media posts were less likely to provide images suitable for individual seal identification (16.5%) than traditional sighting reports (79.9%). However, social media enhanced the ability to detect human-seal interactions or animal disturbances: 22.1%, of the 2,392 Instagram posts examined showed people within 3 meters of a seal, and 17.8% indicated a disturbance to the animal, meanwhile only 0.64% of traditional reports noted a disturbance to the animal. This project demonstrated that data obtained through social media posts have value to monk seal research and management strategies beyond traditional data collection, and further development of social media platforms as data resources is warranted. Many conservation programs may benefit from similar work using social media to supplement the research and conservation activities they are undertaking.


Assuntos
Conservação dos Recursos Naturais , Bases de Dados como Assunto , Focas Verdadeiras/fisiologia , Mídias Sociais , Animais , Animais Selvagens/fisiologia , Monitoramento Ambiental , Hawaii , Atividades Humanas , Humanos
20.
Adv Exp Med Biol ; 1200: 507-543, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31471808

RESUMO

Wildlife conservation requires varying degrees of management of endangered species as well as management of their potential predators and competitors. Conservation also depends on ameliorating human-wildlife conflict, especially where there is a threat to the safety of people and of their pets and livestock. In addition, sustainability of wildlife populations can be affected by feral domestic animals or invasive species, that require removal or control. With the increasing concern for animal welfare, non-lethal methods of limiting population size and distribution, such as fertility control, are gaining favor. Breeding programs in zoos depend on highly effective and selective contraception to manage sustainable insurance populations. This review covers fertility control methods currently in use, those that have not lived up to past promises, and others that are under development and present hope for addressing remaining challenges.


Assuntos
Animais Selvagens/fisiologia , Conservação dos Recursos Naturais , Anticoncepção/veterinária , Fertilidade , Animais , Cruzamento , Densidade Demográfica
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