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1.
Proc Biol Sci ; 287(1935): 20201799, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32962549

RESUMO

Seasonal animal migration is a widespread phenomenon. At the species level, it has been shown that many migratory animal species track similar climatic conditions throughout the year. However, it remains unclear whether such a niche tracking pattern is a direct consequence of individual behaviour or emerges at the population or species level through behavioural variability. Here, we estimated seasonal niche overlap and seasonal niche tracking at the individual and population level of central European white storks (Ciconia ciconia). We quantified niche tracking for both weather and climate conditions to control for the different spatio-temporal scales over which ecological processes may operate. Our results indicate that niche tracking is a bottom-up process. Individuals mainly track weather conditions while climatic niche tracking mainly emerges at the population level. This result may be partially explained by a high degree of intra- and inter-individual variation in niche overlap between seasons. Understanding how migratory individuals, populations and species respond to seasonal environments is key for anticipating the impacts of global environmental changes.


Assuntos
Migração Animal , Aves , Clima , Animais , Mudança Climática , Ecossistema
2.
Nat Commun ; 11(1): 4461, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929068

RESUMO

Protected areas (PAs) are the cornerstones of global biodiversity conservation efforts, but to fulfil this role they must be effective at conserving the ecosystems and species that occur within their boundaries. Adequate monitoring datasets that allow comparing biodiversity between protected and unprotected sites are lacking in tropical regions. Here we use the largest citizen science biodiversity dataset - eBird - to quantify the extent to which protected areas in eight tropical forest biodiversity hotspots are effective at retaining bird diversity. We find generally positive effects of protection on the diversity of bird species that are forest-dependent, endemic to the hotspots, or threatened or Near Threatened, but not on overall bird species richness. Furthermore, we show that in most of the hotspots examined this benefit is driven by protected areas preventing both forest loss and degradation. Our results provide evidence that, on average, protected areas contribute measurably to conserving bird species in some of the world's most diverse and threatened terrestrial ecosystems.


Assuntos
Aves/fisiologia , Conservação dos Recursos Naturais , Florestas , Animais , Biodiversidade , Geografia , América do Sul , Especificidade da Espécie
3.
Science ; 369(6511): 1567-1568, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32973020
4.
Proc Biol Sci ; 287(1934): 20200655, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32900319

RESUMO

Body mass affects many biological traits, but its impacts on immune defences are fairly unknown. Recent research on mammals found that neutrophil concentrations disproportionately increased (scaled hypermetrically) with body mass, a result not predicted by any existing theory. Although the scaling relationship for mammals might predict how leucocyte concentrations scale with body mass in other vertebrates, vertebrate classes are distinct in many ways that might affect their current and historic interactions with parasites and hence the evolution of their immune systems. Subsequently, here, we asked which existing scaling hypothesis best-predicts relationships between body mass and lymphocyte, eosinophil and heterophil concentrations-the avian functional equivalent of neutrophils-among more than 100 species of birds. We then examined the predictive power of body mass relative to life-history variation, as extensive literature indicates that the timing of key life events has influenced immune system variation among species. Finally, we ask whether avian scaling patterns differ from the patterns we observed in mammals. We found that an intercept-only model best explained lymphocyte and eosinophil concentrations among birds, indicating that the concentrations of these cell types were both independent of body mass. For heterophils, however, body mass explained 31% of the variation in concentrations among species, much more than life-history variation (4%). As with mammalian neutrophils, avian heterophils scaled hypermetrically (b = 0.19 ± 0.05), but more steeply than mammals (approx. 1.5 ×; 0.11 ± 0.03). As such, we discuss why birds might require more broadly protective cells compared to mammals of the same body size. Overall, body mass appears to have strong influences on the architecture of immune systems.


Assuntos
Aves , Tamanho Corporal , Sistema Imunitário , Animais , Evolução Biológica , Traços de História de Vida , Filogenia
5.
Sci Total Environ ; 741: 140220, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887000

RESUMO

Human-dominated environments alter the availability and quality of resources for many species, especially for scavengers that have large home ranges and plastic foraging behaviors that enable them to exploit novel resources. Along the western slope of the Andes, the modification of natural landscapes have resulted in significant declines in native prey, the introduction of non-native species, and an increase in the availability of anthropogenic resources. These factors have likely influenced the resources available to Andean condors (Vultur gryphus), however, data are lacking as to how condor's diet vary along their large latitudinal range. We evaluated differences in Andean condor diet along a ~2500 km latitudinal gradient in Chile from the heavily modified Central zone (32-34°S) to the more pristine Austral zone (44-56°S). We assessed diet composition through the identification of prey remains in condor pellets, and carbon and nitrogen isotope analysis of condor feathers and their primary prey identified from pellet analysis. Our results identified medium- and large-bodied domesticated mammals (ungulates) and introduced exotic species (lagomorphs) as common prey across the study area. Condors from the Central zone had the largest isotopic niche width, probably related to consumption of anthropogenic resources with distinctly high carbon isotope values indicative of C4-based foods likely acquired from landfills or corn-fed livestock. Isotopic niches for condors from the Southern and Austral zones almost completely overlapped. Andean condor diet is strongly influenced by local conditions determining differential access to prey sources. The high dependence of Andean condors on livestock across a large geographical area, and landfills in more (sub)urban areas, may help stabilize their populations via anthropogenic resources subsidies. Long-term dependence on such resources, however, may have health costs including contaminant exposure and greater mortality risk. These data will help identify potential threats related to resource availability and use, and better inform management and conservation decisions.


Assuntos
Aves , Comportamento Alimentar , Animais , Chile , Dieta , Plumas , Humanos
6.
Mar Pollut Bull ; 159: 111471, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32892914

RESUMO

Plastic ingestion by seabirds is an efficient way to monitor marine plastics. We report temporal variation in the characteristics of marine litter regurgitated by albatrosses and giant petrels on sub-Antarctic Marion Island between 1996 and 2018. Both fishery and other litter peaked during the height of the Patagonian toothfish fishery around the island (1997-1999). Comparing the two subsequent decades of reduced fishing effort (1999-2008 and 2009-2018), fishing litter decreased while other litter increased across all species. Litter increased most in grey-headed albatrosses, followed by giant petrels and wandering albatrosses. Similar ranked responses were found in the same species at South Georgia, but non-fishery-related litter has increased faster in the Indian Ocean than the southwest Atlantic, indicating regional changes in litter growth rates. These seabirds' regurgitations provide an easy, non-invasive way to track changes in oceanic litter in a remote area that is otherwise difficult to monitor.


Assuntos
Monitoramento Ambiental , Plásticos , Animais , Regiões Antárticas , Aves , Oceano Índico , Ilhas , Resíduos
7.
Mar Environ Res ; 160: 104989, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907727

RESUMO

Expansion of offshore wind energy is vital for the reduction of CO2 emissions. However, offshore wind farms may negatively impact the environment without proper planning. Here we assess the robustness of the conclusions of earlier studies that the strictly protected red-throated diver, Gavia stellata, is strongly displaced from wind farms in the German Bight (North Sea). We modelled the distribution of divers based on two independent data sets, digital aerial surveys and satellite telemetry, in relation to the dynamic offshore environment and anthropogenic pressures. Both data types found that divers were strongly displaced from wind farms in suitable habitat. The displacement effect gradually decreased with distance from the wind farms (being very strong up to 5 km away), but a significant effect could be detected up to 10-15 km away. The telemetry data further indicated that the displacement distance decreased with decreasing visibility. The displacement distance was also shorter during the day than during the night, potentially as a response to aviation and navigation lights of the wind farms. These findings should be taken into consideration in marine spatial planning to avoid cumulative impacts on red-throated diver populations.


Assuntos
Aves , Fontes Geradoras de Energia , Telemetria , Vento , Animais , Mar do Norte , Inquéritos e Questionários
8.
PLoS One ; 15(8): e0236631, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797051

RESUMO

Pelagic seabirds are elusive species which are difficult to observe, thus determining their spatial distribution during the migration period is a difficult task. Here we undertook the first long-term study on the distribution of migrating shearwaters from data gathered within the framework of citizen science projects. Specifically, we collected daily abundance (only abundance given presence) of Balearic shearwaters from 2005 to 2017 from the online databases Trektellen and eBird. We applied machine-learning techniques, specifically Random Forest regression models, to predict shearwater abundance during migration using 15 environmental predictors. We built separated models for pre-breeding and post-breeding migration. When evaluated for the total data sample, the models explained more than 52% of the variation in shearwater abundance. The models also showed good ability to predict shearwater distributions for both migration periods (correlation between observed and predicted abundance was about 70%). However, relative variable importance and variation among the models built with different training data subsamples differed between migration periods. Our results showed that data gathered in citizen science initiatives together with recently available high-resolution satellite imagery, can be successfully applied to describe the migratory spatio-temporal patterns of seabird species accurately. We show that a predictive modelling approach may offer a powerful and cost-effective tool for the long-term monitoring of the migratory patterns in sensitive marine species, as well as to identify at sea areas relevant for their protection. Modelling approaches can also be essential tools to detect the impacts of climate and other global changes in this and other species within the range of the training data.


Assuntos
Migração Animal , Aves , Ciência do Cidadão , Espécies em Perigo de Extinção , Animais , Cruzamento , Bases de Dados como Assunto , Europa (Continente) , Aprendizado de Máquina , Modelos Biológicos , Modelos de Interação Espacial , Estações do Ano , Análise Espaço-Temporal
9.
PLoS One ; 15(8): e0236925, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857761

RESUMO

In the age of machine learning, building programs that take advantage of the speed and specificity of algorithm development can greatly aid efforts to quantify and interpret changes in animal behavior in response to abiotic environmental factors, like temperature. For both endotherms and ectotherms, temperature can affect everything from daily energy budgets to nesting behaviors. For instance, in birds environmental temperature plays a key role in shaping parental incubation behavior and temperatures experienced by embryos. Recent research indicates that temperatures experienced by embryos affect viability and are important in shaping fitness-related traits in young birds, sparking renewed interest in relationships among environmental factors, parental incubation behavior, and incubation temperature. Incubation behavior of birds can be monitored non-invasively by placing thermal probes into the nest and analyzing temperature fluctuations that occur as parents attend and leave the nest (on- and off-bouts, respectively). When other measures of temperature (e.g., ambient air or operative temperature) are collected simultaneously with incubation temperature it is possible to compare shifts in behavior with environmental changes. To improve analysis of incubation behavior using these large thermal data sets we developed a program, NestIQ, that uses machine learning to guide parameter optimization allowing it to track the behavior of diverse species. NestIQ's algorithm was tested using six species incubating in lab or field scenarios, that exhibit unique incubation patterns. This stand-alone and open source software is operated through a graphical user interface (i.e., no user programming is required) that provides important behavioral and thermal output statistics. Further, measures of environmental temperature can be imported alongside nest temperature into the program, which then reports various attributes of environmental temperature during shifts in parental behavior. This program will improve the ability of avian ecologists to interpret a critical parental care behavior that can be used across diverse incubation scenarios and species. Although specifically designed for quantifying avian incubation, NestIQ has the potential for broader applications, including basking and nesting behaviors of non-avian reptiles in relation to ambient temperature.


Assuntos
Aves , Fenômenos Ecológicos e Ambientais , Aprendizado de Máquina , Comportamento de Nidação , Temperatura , Animais , Software
10.
BMC Bioinformatics ; 21(Suppl 10): 354, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32838732

RESUMO

BACKGROUND: Type A influenza viruses circulate and spread among wild birds and mostly consist of low pathogenic strains. However, fast genome variation timely results in the insurgence of high pathogenic strains, which when infecting poultry birds may cause a million deaths and strong commercial damage. More importantly, the host shift may concern these viruses and sustained human-to-human transmission may result in a dangerous pandemic outbreak. Therefore, fingerprints specific to either low or high pathogenic strains may represent a very important tool for global surveillance. RESULTS: We combined Normal Modes Analysis and surface electrostatic analysis of a mixed strain dataset of influenza A virus haemagglutinins from high and low pathogenic strains in order to infer specific fingerprints. Normal Modes Analysis sorted the strains in two different, homogeneous clusters; sorting was independent of clades and specific instead to high vs low pathogenicity. A deeper analysis of fluctuations and flexibility regions unveiled a special role for the 110-helix region. Specific sorting was confirmed by surface electrostatics analysis, which further allowed to focus on regions and mechanisms possibly crucial to the low-to-high transition. CONCLUSIONS: Evidence from previous work demonstrated that changes in surface electrostatics are associated with the evolution and spreading of avian influenza A virus clades, and seemingly involved also in the avian to mammalian host shift. This work shows that a combination of electrostatics and Normal Modes Analysis can also identify fingerprints specific to high and low pathogenicity. The possibility to predict which specific mutations may result in a shift to high pathogenicity may help in surveillance and vaccine development.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A/metabolismo , Vírus da Influenza A/patogenicidade , Eletricidade Estática , Algoritmos , Animais , Animais Selvagens/virologia , Aves/virologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Influenza Aviária/virologia , Modelos Moleculares , Domínios Proteicos
11.
PLoS One ; 15(8): e0236417, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790700

RESUMO

Natural history collections are yielding more information as digitization brings specimen data to researchers, connects specimens across museums, and as new technologies allow for more large-scale data collection. Therefore, a key goal in specimen digitization is developing methods that both increase access and allow for the highest yield of phenomic data. 3D digitization is increasingly popular because it has the potential to meet both aspects of that key goal. However, current methods overlook or do not prioritize some of the most sought-after phenotypic traits, those involving the external appearance of specimens, especially color. Here, we introduce an efficient and cost-effective pipeline for 3D photogrammetry to capture the external appearance of natural history specimens and other museum objects. 3D photogrammetry aligns and compares sets of dozens, hundreds, or even thousands of photos to create 3D models. The hardware set-up requires little physical space and around $3,000 in initial investment, while the software pipeline requires $1,400/year for proprietary software subscriptions (with open-source alternatives). The creation of each 3D model takes 1-2 hours/specimen and much of the software pipeline is automated with minimal supervision required, including the onerous step of mesh processing. We showcase the method by creating 3D models for most of the type specimens in the Moore Laboratory of Zoology bird collection and show that digital bill measurements are comparable to hand-taken measurements. Color data, while not included as part of this pipeline, is easily extractable from the models and one of the most promising areas of data collection. Future advances can adapt the method for ultraviolet reflectance capture and increased efficiency and model quality. Combined with genomic data, phenomic data from 3D models including photogrammetry will open new doors to understanding organismal evolution.


Assuntos
Imageamento Tridimensional/métodos , Museus , História Natural/métodos , Fotogrametria/métodos , Animais , Aves/anatomia & histologia , Análise Custo-Benefício , Imageamento Tridimensional/economia , Museus/economia , História Natural/economia , Fotogrametria/economia , Software , Fatores de Tempo , Fluxo de Trabalho
12.
PLoS One ; 15(8): e0237168, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760155

RESUMO

Disease transmission can be identified in a social network from the structural patterns of contact. However, it is difficult to separate contagious processes from those driven by homophily, and multiple pathways of transmission or inexact information on the timing of infection can obscure the detection of true transmission events. Here, we analyze the dynamic social network of a large, and near-complete population of 16,430 zoo birds tracked daily over 22 years to test a novel "friends-of-friends" strategy for detecting contagion in a social network. The results show that cases of avian mycobacteriosis were significantly clustered among pairs of birds that had been in direct contact. However, since these clusters might result due to correlated traits or a shared environment, we also analyzed pairs of birds that had never been in direct contact but were indirectly connected in the network via other birds. The disease was also significantly clustered among these friends of friends and a reverse-time placebo test shows that homophily could not be causing the clustering. These results provide empirical evidence that at least some avian mycobacteriosis infections are transmitted between birds, and provide new methods for detecting contagious processes in large-scale global network structures with indirect contacts, even when transmission pathways, timing of cases, or etiologic agents are unknown.


Assuntos
Doenças das Aves/transmissão , Infecções por Mycobacterium/transmissão , Comportamento Social , Animais , Animais de Zoológico/microbiologia , Animais de Zoológico/fisiologia , Aves/microbiologia , Aves/fisiologia , Modelos Estatísticos
13.
Nature ; 584(7821): 398-402, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32759999

RESUMO

Land use change-for example, the conversion of natural habitats to agricultural or urban ecosystems-is widely recognized to influence the risk and emergence of zoonotic disease in humans1,2. However, whether such changes in risk are underpinned by predictable ecological changes remains unclear. It has been suggested that habitat disturbance might cause predictable changes in the local diversity and taxonomic composition of potential reservoir hosts, owing to systematic, trait-mediated differences in species resilience to human pressures3,4. Here we analyse 6,801 ecological assemblages and 376 host species worldwide, controlling for research effort, and show that land use has global and systematic effects on local zoonotic host communities. Known wildlife hosts of human-shared pathogens and parasites overall comprise a greater proportion of local species richness (18-72% higher) and total abundance (21-144% higher) in sites under substantial human use (secondary, agricultural and urban ecosystems) compared with nearby undisturbed habitats. The magnitude of this effect varies taxonomically and is strongest for rodent, bat and passerine bird zoonotic host species, which may be one factor that underpins the global importance of these taxa as zoonotic reservoirs. We further show that mammal species that harbour more pathogens overall (either human-shared or non-human-shared) are more likely to occur in human-managed ecosystems, suggesting that these trends may be mediated by ecological or life-history traits that influence both host status and tolerance to human disturbance5,6. Our results suggest that global changes in the mode and the intensity of land use are creating expanding hazardous interfaces between people, livestock and wildlife reservoirs of zoonotic disease.


Assuntos
Biodiversidade , Especificidade de Hospedeiro , Zoonoses/microbiologia , Zoonoses/parasitologia , Zoonoses/virologia , Animais , Aves/microbiologia , Aves/parasitologia , Aves/virologia , Humanos , Mamíferos/microbiologia , Mamíferos/parasitologia , Mamíferos/virologia , Especificidade da Espécie , Zoonoses/transmissão
14.
Wiad Lek ; 73(4): 831-834, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32731727

RESUMO

West Nile Fever (WNF) is the most common arbovirus infection caused by West Nile Virus (WNV), which has been responsible for numerous epidemic outbreaks of disease among humans, birds and horses on all continents, with the exception of Antarctica, over the past two decades. On the territory of Ukraine, the earliest reports of cases of WNV circulation in humans and birds relate to the 70s of the XX century. In Poltava region WNF was first registered in 2011. Though the epidemiological and clinical patterns of WNF in Ukraine and Poltava region remain understudied, primarily due to the lack of alertness of practitioners to the problem of WNF and to broader access to laboratory diagnosis of the disease. The first clinical case of West Nile Viral encephalitis, registered on the territory of Poltava region, has been given and analyzed.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Aves , Surtos de Doenças , Cavalos , Humanos , Ucrânia
15.
Sci Total Environ ; 737: 140238, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783846

RESUMO

Wind energy is a key component of climate action strategies aimed at reducing our dependence on fossil fuels. Despite providing environmental benefits, there are increasing concerns surrounding the impact of wind farms on wildlife, with research indicating that effects on wildlife can be highly variable between species, regions, and sites. In light of this variability and the accelerating growth of the wind energy sector globally, a comprehensive understanding of wind farm effects on wildlife and ease of access to this knowledge are pivotal to inform best practice if wind energy is to become a truly sustainable source of energy. This review evaluates interactions between a globally distributed bird genus (harriers, Circus sp.) and wind farms to assess broader patterns in wildlife-wind energy knowledge accessibility and bias. A systematic review of grey and peer-reviewed literature across two multidisciplinary and two field-specific databases in two languages (English and Spanish) yielded 235 relevant sources, covering 12 harrier species and 31 countries. Findings indicate that harriers are considered to have high sensitivity to wind farms, with greatest impacts expected from habitat effects rather than from turbine collisions. In the broader wildlife-wind energy context, this study underscores (i) the predominance of grey literature and of sources solely documenting species-wind farm overlaps; (ii) limitations in grey literature availability and peer-reviewed publication accessibility; (iii) lack of standardized research and monitoring practices; and (iv) evidence of language, taxonomic, and geographic bias in literature sources. Overall, findings demonstrate that limited accessibility to wildlife-wind energy knowledge risks widening the research-implementation gap. Widespread implementation of open practices that allow researchers and practitioners to build on existing knowledge (e.g. national and international online repositories and databases, knowledge sharing and collaborative initiatives, open access publications) is crucial if ongoing wind energy development efforts are to be successfully aligned with conservation priorities.


Assuntos
Fontes Geradoras de Energia , Vento , Animais , Animais Selvagens , Aves , Ecossistema
16.
Sci Total Environ ; 737: 140250, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783849

RESUMO

Forest fragments in urban parks provide important habitat for birds. However, the guano deposited by large aggregations of birds in such fragments can dramatically change soil properties, which in turn, can alter soil microbial community composition, potentially affecting the forests' composition and survival. To investigate the effects of bird aggregations on the soil of fragmented urban forests, we compared the soil properties and microbial communities of two forested islands, one in Liuhuahu park and the other in Wanzuitou park, Guangzhou, where large numbers of birds aggregate yearly to nest. Comparison to sites without bird aggregations suggests that decades of guano deposition appears to have caused soil acidification and an increase in soil nutrients. The relative abundance of the soil bacterial phylum Actinobacteria and the soil fungal phylum Ascomycota were significantly lower in soil under bird aggregations. The aerobic nitrite oxidation, nitrate reduction and cellulolysis bacterial guilds were significantly less abundant under bird aggregations in Liuhuahu park. The wood saprotroph fungi guild was significantly less abundant under the bird aggregation in Liuhuahua park and the pathogenic fungi guild significantly more abundant in Wanzuitou park. Soil properties, including TN, NO3--N, TOC and pH, explained the variation in Ascomycota and Basidiomycota abundance, and the alpha-diversity of the fungal community. Microbial community variation could potentially slow the rate of decomposition and disease resistance of plant in these forests. We suggest that sufficient contiguous forest should be maintained in urban areas to reduce the density of bird aggregations in isolated forest fragments.


Assuntos
Microbiota , Solo , Animais , Aves , Florestas , Microbiologia do Solo
17.
Sci Total Environ ; 739: 140356, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758969

RESUMO

The role of wild birds in the carriage and transmission of human and food animal bacteria with resistant genotypes has repeatedly been highlighted. However, few studies have focussed on the specific exposure sources and places of acquisition and selection for antimicrobial-resistant bacteria in vultures relying on livestock carcasses across large areas and different continents. The occurrence of bacterial resistance to antimicrobial agents was assessed in the faecal microbiota of sedentary Griffon vultures (Gyps fulvus) and trans-Saharan migratory Egyptian vultures (Neophron percnopterus) in central Spain. High rates (generally >50%) of resistant Escherichia coli and other enterobacteria to amoxicillin, cotrimoxazole and tetracycline were found. About 25-30% of samples were colonised by extended-spectrum beta-lactamases (ESBL) producing bacteria, while 5-17% were positive for plasmid mediated quinolone resistance (PMQR) phenotypes, depending on vulture species and age. In total, nine ESBL types were recorded (7 in griffon vultures and 5 in Egyptian vultures), with CTX-M-1 the most prevalent in both species. The most prevalent PMQR was mediated by qnrS genes. We found no clear differences in the occurrence of antimicrobial resistance in adult vultures of each species, or between nestling and adult Egyptian vultures. This supports the hypothesis that antimicrobial resistance is acquired in the European breeding areas of both species. Bacterial resistance can directly be driven by the regular ingestion of multiple active antimicrobials found in medicated livestock carcasses from factory farms, which should be not neglected as a contributor to the emergence of novel resistance clones. The One Health framework should consider the potential transboundary carriage and spread of epidemic resistance from high-income European to low-income African countries via migratory birds.


Assuntos
Antibacterianos , Aves , África , África do Norte , Agricultura , Animais , Fazendas , Humanos , Plasmídeos , Espanha , beta-Lactamases
18.
Oecologia ; 193(4): 913-924, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32772157

RESUMO

In semi-arid environments, the marked contrast in temperature and precipitation over the year strongly shapes ecological communities. The composition of species and their ecological interactions within a community may vary greatly over time. Although intra-annual variations are often studied, empirical information on how plant-bird relationships are structured within and among years, and how their drivers may change over time are still limited. In this study, we analyzed the temporal dynamics of the structure of plant-hummingbird interaction networks by evaluating changes in species richness, diversity of interactions, modularity, network specialization, nestedness, and ß-diversity of interactions throughout four years in a Mexican xeric shrubland landscape. We also evaluated if the relative importance of abundance, phenology, morphology, and nectar sugar content consistently explains the frequency of pairwise interactions between plants and hummingbirds across different years. We found that species richness, diversity of interactions, nestedness, and network specialization did vary within and among years. We also observed that the ß-diversity of interactions was high among years and was mostly associated with species turnover (i.e., changes in species composition), with a minor contribution of interaction rewiring (i.e., shifting partner species at different times). Finally, the temporal co-occurrence of hummingbird and plant species among months was the best predictor of the frequency of pairwise interactions, and this pattern was consistent within and among years. Our study underscores the importance of considering the temporal scale to understand how changes in species phenologies, and the resulting temporal co-occurrences influence the structure of interaction networks.


Assuntos
Aves , Polinização , Animais , México , Néctar de Plantas , Plantas
19.
Mar Pollut Bull ; 158: 111435, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32753218

RESUMO

Phthalates, plastic-derived contaminants, are of increasing global concern. This study quantified phthalates in seabirds collected across >1700 km of the Aleutian Islands, Alaska, and contributes to a body of knowledge on plastic contaminants in marine wildlife. We measured six phthalate congeners in seabirds representing ten species and four feeding guilds. Phthalates were detected in 100% of specimens (n = 115), but varied among individuals (3.64-539.64 ng/g). DEHP and DBP occurred at an order of magnitude higher than other congeners. Total phthalates did not vary geographically, but differed among feeding guilds, with significantly higher concentrations in diving plankton-feeders compared to others. Plastic particles were detected in 36.5% of randomly subsampled seabird stomachs (n = 74), suggesting plastic ingestion as a potential route of phthalate exposure. Our findings suggest feeding behavior could influence exposure risk for seabirds and lend further evidence to the ubiquity of plastic pollutants in marine ecosystems.


Assuntos
Plásticos , Poluentes Químicos da Água/análise , Alaska , Animais , Aves , Ecossistema , Monitoramento Ambiental
20.
Oecologia ; 193(4): 1021-1026, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32766935

RESUMO

Migration has evolved to tackle temporal changes in availability of resources. Climate change has been shown to affect the migration dates of species, which raises the question of whether the variation in the timing of migration is climate or resource dependent? The relative importance of temperature and availability of food as drivers of migration behaviour during both spring and autumn seasons has been poorly studied. Here, we investigated these patterns in frugivorous and granivorous birds (hereafter frugivorous) that are assumed to postpone their autumn migration when there is plenty of food available, which may also advance upcoming spring migration. On the other hand, especially spring migration dates have been negatively connected with increasing temperatures. We tested whether the autumn and spring migration dates of eleven common frugivorous birds depended on the crop size of trees or ambient temperatures using 29 years of data in Finland. The increased crop sizes of trees delayed autumn migration dates; whereas, autumn temperature did not show a significant connection. We also observed a temporal trend towards later departure. Increasing temperature and crop sizes advanced spring arrival dates. Our results support the hypothesis that the timing of autumn migration in the frugivorous birds depends on the availability of food and is weakly connected with the variation in temperature. Importantly, crop size can have carry-over effects and affect the timing of spring arrival possibly because birds have overwintered closer to the breeding grounds after an abundant crop year.


Assuntos
Migração Animal , Árvores , Animais , Aves , Finlândia , Estações do Ano , Temperatura
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