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The Zygocotylidae Ward, 1917 is a compact family of amphistome digeneans that until now comprised 2 genera, each represented by a single species: Zygocotyle lunata (Diesing, 1836) Stunkard, 1916 and Wardius zibethicus Barker and East, 1915 in Barker 1915. Despite highly similar morphology, these genera are separated based on the presence (Zygocotyle) or absence (Wardius) of posterolateral projections (=lappets) on the ventral sucker and esophageal bulb. In the present study, we generated partial large ribosomal subunit (28S), internal transcribed spacer 2 (ITS2) rDNA, and cytochrome c oxidase subunit 1 (COI) sequences of Z. lunata from several hosts (12 avian and 1 rodent species) throughout North and South America as well as 28S and COI sequences of W. zibethicus from muskrat in North America. The newly generated 28S sequences were used for sequence comparison and phylogenetic analysis. The COI sequences were used for species-level comparisons. Our analysis revealed a close relationship and high sequence similarity between Z. lunata and W. zibethicus. Considering the low morphological and genetic differences, we synonymize ZygocotyleStunkard, 1916 with Wardius Barker and East, 1915 in Barker 1915 and transfer Z. lunata to Wardius as Wardius lunatus (Diesing, 1836) n. comb.

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The Great Shearwater, Ardenna gravis, is the largest and most abundant species of procellarid seabirds in the South Atlantic. A specimen of this shearwater was found dead and parasitized by a hard tick on Cima Beach, Santa Catarina State, southern Brazil. Morphological and molecular analyses confirmed the tick's identity as Ixodes uriae. Molecular screening for Rickettsiales and Piroplasmida was conducted, and all results were negative, suggesting no immediate health threats. This study reports the first occurrence of this hard tick species parasitizing A. gravis in southern Brazil, highlighting the ecological and epidemiological implications of this finding. This record contributes to the understanding of tick-host interactions in migratory seabirds and emphasizes the need for further research on the ecological roles and health implications of ectoparasites in these avian populations.

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Acoustic communities are acoustically active species aggregations within a habitat, where vocal interactions between species can interfere their communication. The acoustic adaptation hypothesis (AAH) explains how the habitat favors the transmission of acoustic signals. To understand how bird acoustic communities are structured, we tested the effect of habitat structure on the phylogenetic structure, and on the phylogenetic and vocal diversity of acoustic communities in a semi-arid zone of Mexico. From autonomous recordings in three types of vegetation (crop fields, tetecheras, and mesquiteras), which differ in terms of complexity and canopy openness, we evaluated sound attenuation, and estimated metrics of phylogenetic structure and diversity as well as acoustic diversity with the use of two indices. Mesquiteras showed greater vegetation density, more attenuation, more vocal diversity, as well as a phylogenetic structure that tended towards overdispersion, in contrast to crop fields that showed less vegetation density, less attenuation, less vocal diversity and more phylogenetic relatedness, while tetecheras showed intermediate patterns. Phylogenetic structure was explained by vegetation density and excess attenuation. The higher vocal diversity, phylogenetic structure tended towards overdispersion. These results suggest a role for environmental filters in the crop fields, where more closely related species with similar vocal characteristics coexist (supporting AAH), and probably competitive exclusion in the mesquiteras, where more distantly related species coexist, promoting vocal diversity. This study offers information about the influence of habitat on the acoustic community structure, which could inform our understanding of the distribution of species from acoustic perspective.

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Environmental characteristics drastically shape the host-parasite associations under natural conditions. This is the case of parasites such as avian haemosporidians which naturally infect birds and are transmitted by insect vectors. Landscape characteristics are known to determine the epidemiology of transmission of these parasites in the wild, but the strength of these factors may differ at different spatial scales. We studied the effects of the landscape structure and environmental variables on the prevalence and richness of lineages of avian haemosporidian parasites (genera Plasmodium, Haemoproteus and Leucocytozoon) infecting birds in a highly diverse area of Antioquia, Colombia. We screened blood samples from 678 individuals across 90 bird species for number of infections, prevalence and richness of haemosporidian lineages in sites surrounding three hydroelectric dams. We obtained environmental and landscape structure variables around the bird sampling points at different spatial scales (from 50 to 500 m radii, every 50 m) and selected the most important ones. We modelled the relationships between parasite infection variables and landscape structural and environmental characteristics. Effects of landscape structure on variables reflecting haemosporidian infections varied according to the selected scale of analyses. The scale of the effect of landscape structure was larger for the number of infections and prevalence (Average = 350 and 425 m radius) than for lineage richness (Average = Plasmodium 219 m, Haemoproteus 244 m). Agricultural patch density notably increased number of infection rates (pseudo-R2 = 0.68). The number of infections and the richness of Haemoproteus lineages correlated with agricultural connectivity at larger scales (500 m). Haemosporidian prevalence was primarily linked with proportion forest and agricultural covers. Haemoproteus richness was influenced by connectivity and NDVI - Normalized Difference Vegetation Index (pseudo-R2 = 0.83), while Plasmodium richness was affected by anthropogenic density, edge density, forest proportion, and temperature (pseudo-R2 = 0.79). Changes in parasite infection and prevalence remain difficult to predict, as each parasite-host system is susceptible to many unaccounted variables. This study found that transformed landscapes, particularly density of anthropogenic and agricultural patches nearby increases haemosporidian parasites at different scales. These findings underscore the complex interplay between landscape structure and haemosporidian infections in avian hosts in tropical ecosystems.

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Land use change from wildlands to urban and productive environments can dramatically transform ecosystem structure and processes. Despite their structural and functional differences from wildlands, human-modified environments offer unique habitat elements for wildlife. In this study, we examined how migratory birds use urban, productive, and wildland environments of a highly anthropized region of Western Mexico known as "El Bajío". We used Generalized Linear Models to compare species richness, abundance, and the functional traits of migratory bird assemblages among these three environments. Results revealed differences in species richness, composition, and the functional traits of migratory birds among environments. Regardless of wildlands showing medium to high levels of human disturbance, they presented the highest species richness and abundance of migratory birds, with urban environments presenting the lowest values. Insectivorous and granivorous birds were dominant in the migratory bird assemblages of the three environments. The migratory bird assemblages of productive environments had more grassland granivorous birds. In contrast, insectivorous birds with dense habitat preferences and short culmen lengths dominated the urban bird assemblage. Migratory bird assemblages in productive and urban environments showed similar species richness and abundance of insectivorous birds, but they differ in their composition. Our results reveal that urban trees allowed cities to function as simplified forests, showing that the urban environment has the untapped potential to support complex assemblages of migratory birds. To promote migratory birds in human-modified landscapes, we must maintain complex vegetation areas that allow birds with diverse functional traits to overwinter in urban and productive environments.

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ardeids are wild birds well adapted to urban and periurban environments. However, the association of wildlife with humans and livestock increases the chances of transmission of microorganisms between wild animals, domestic animals and humans. The present study aimed to investigate the occurrence of Salmonella spp., Escherichia coli and Staphylococcus aureus in Ardeids living in a nest located on the Campus of the Universidade Federal de Lavras (UFLA), in Lavras, Minas Gerais, Southeast Region of Brazil. Ten great egrets (Ardea alba) and five cattle egrets (Bubulcus ibis) found dead or dying were collected for the study, examined, and cloacal swabs were collected from each bird. Most of these birds (92.85 %) were chicks. Necropsy was carried out, after euthanasia of the dying animals. Organs/tissues samples from all birds were collected for histopathologic exam and for microbiologic analysis when macroscopic lesions were present. Salmonella spp. were detected in 42.85 % of the collected egrets and E. coli in 64.28 %. Staphylococcus aureus was not detected in any of them. The vast majority of PCR positive colonies was obtained by cloacal swab, which means that the agents were being eliminated by the birds' excreta and may represent a significant public health concern.

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BACKGROUND: The proximity between people and their domestic animals with wild animal populations can result in the spread of diseases with a significant impact on public health. Infection by parasites in wildlife is considered an important bioindicator of the current state of ecosystems, and studying the epidemiology of these infections is essential for a better understanding of natural foci. However, research on parasites in southern Brazil, especially in Rio Grande do Sul (RS), is considered incipient. Therefore, in this study, we aimed to identify the parasitic fauna of wild animals in the southern region of RS through fecal parasitological diagnosis. We processed 82 fecal samples from wild animals - including birds, mammals, and reptiles - from cities within the microregion of Pelotas, using the Zinc Sulfate Centrifugal Flotation, Spontaneous Sedimentation and Oocyst Sporulation techniques. RESULTS: In 69.5% of the samples (93.1% of mammals, 47% of birds and 50% of reptiles), we found helminth eggs and/or protozoan cysts/oocysts, with strongylid-type eggs being the most frequent parasites (44.11%). Additionally, 64.9% of the positive samples were parasitized by at least one morphogroup with zoonotic agents (Taeniidae, Capillaria, Strongyloides, Spirometra, Lagochilascaris, Sarcocystis, Trichuris, Giardia, Ancilostomid, Physaloptera, Toxocara, Fasciola). We also recorded the first finding of Monocystis spp. in a Southern tamandua (Tamandua tetradactyla). CONCLUSIONS: Thus, it was observed that the majority of the animals were parasitized and, consequently, susceptible to a wide range of pathogens of medical and veterinary interest, highlighting the importance of these hosts in the spread of parasites, especially those with zoonotic potential. However, the ecology of transmission and the role of these hosts in the life cycles of parasites should be further explored in other studies.

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Among the many changes associated with the urbanization process, changes in resource availability can directly impact local wildlife populations. Urban areas suppress native vegetation and convert natural environments into impervious surfaces, modifying the composition and quantity of available food resources. Understanding the food requirements of species is crucial, mainly because it is one of the main elements that characterize their ecological niche and structure local communities. Our aim in this study was to assess the impact of urbanization intensity on the isotopic niche space of birds commonly found in urban areas of Brasília, the capital of Brazil, a big city in central Brazil with approximately 3 million inhabitants. By analyzing the δ13C and δ15N isotopic metrics of feathers from bird species found along a gradient of urbanization intensity, we evidenced a simplification but not a displacement of the bird assembly isotopic space due to urban intensification. Bird assemblage access similar food resources in the higher urban intensification areas, although less diversified than in lower urban intensification areas. In most cases, the response to urban intensification is more specific than convergent among guild members. The studied species maintain themselves in highly intensified urban areas by restricting, changing, and expanding their access to resources. The trophic dimension is one of the key components of the species' ecological niche, and understanding the urban intensification impacts on this dimension is essential for maintaining biodiversity and ecosystem services in cities.

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In this case study, we describe an outbreak of highly pathogenic avian influenza (HPAI) virus subtype H7N3 in an ecological reserve in Chiapas, Mexico, affecting captive and wild birds. The virus was detected mainly in plain chachalacas displaying respiratory and gastrointestinal clinical signs and death within 24 hours. Mortality in white-fronted parrots and a clay-colored thrush was also recorded. We describe control strategies implemented to prevent virus dissemination and active surveillance within the risk area. Phylogenetic analysis revealed that the HPAI H7N3 virus detected in affected birds shared a close genetic relationship with Mexican H7N3 isolates from 2012.

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The Gould's Toucanet Selenidera gouldii (Natterer, 1837) occurs mainly in eastern Amazonia, with a geographically isolated population in the northeast Brazilian state of Ceará. Based on two male specimens from the latter population that appeared to have a smaller body and bill with a relatively large black patch, Pinto & Camargo (1961) described the subspecies S. g. baturitensis. This taxon has long been known in museum collections only by the two male specimens mentioned in its description, but recently obtained specimens have now permitted a test of its validity with larger sample sizes. Here, I examined the largest sample of S. g. baturitensis studied to date to show that S. g. gouldii and S. g. baturitensis are just the east and west ends of a broad geographic pattern of smoothly clinal differences in morphometrics that were categorized as subspecies taxa.

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The Rio Doce Hydrographic Basin (RDB) lies almost completely in the Brazilian Atlantic Forest, a highly threatened tropical rainforest. The RDB has suffered dramatic anthropogenic impacts during the last two centuries and is currently one of the most degraded regions in southeastern Brazil. In this paper, we gathered 140,742 bird records collected since the early 19th by more than two thousand naturalists, professional scientists, and citizen scientists. This vast database was compiled from several sources, including published literature, unpublished technical reports, natural history museums, and citizen science platforms. After checking and standardizing the database, we found high species richness in the RDB, with 689 species recorded to date, from which 675 (98%) were documented by specimens or digital vouchers. This database is presented as a detailed catalogue, including maps containing all localities in which each species has been recorded. We present text accounts for 40 noteworthy species recorded in the RDB, and a complete gazetteer for the 636 localities sampled. Preliminary analyses reveal that the RDB avifauna suffered a dramatic change in its species composition during the last two centuries, mostly due to human activity. Highly sensitive species associated to pristine forests vanished, while species associated to dry and open habitat expanded their ranges in the RDB. Finally, in addition to thoroughly characterization of the RDB avifauna, this paper provides the basis for a series of studies about the avifauna of one of the hottest hotspots of biodiversity in the entire Neotropical region.

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Flamingos in managed care are vulnerable to inflammatory states, including pododermatitis, trauma, and capture myopathy. Fatty acids are an important component of well-balanced nutrition and crucial to endogenous immune responses associated with these conditions, yet fatty acids have not been assessed in flamingos. This study reported complete whole blood circulating fatty acid profiles in two flamingo species in managed care receiving different diets. Whole blood from Chilean flamingos (Phoenicopterus chilensis) (n=16) and Caribbean flamingos (Phoenicopterus ruber) (n=17) was collected during routine exams and prepared on blood spot cards for complete fatty acid profile analysis in which 24 individual fatty acids, nine fatty acids groups, and four calculated parameters were quantifiable. Non-parametric statistical analysis compared profiles between species, and between sex of Chilean flamingos. The median ratio of omega-6/omega-3 fatty acids was 5.64. Chilean flamingos had significantly (P<0.05) higher percentages of 11 individual fatty acids, total polyunsaturated and highly unsaturated fatty acids, total omega-3 and omega-6 fatty acids, arachidonic acid (AA; 20:4w6)/eicosapentaenoic acid (EPA; 20:5w3) ratio, and total EPA + DHA, whereas Caribbean flamingos had significantly (P<0.05) higher percentages of eight individual fatty acids, and total saturated fatty acids. Male Chilean flamingos had significantly (P<0.05) higher percentages of AA, EPA, and total polyunsaturated fatty acids, whereas females had significantly (P<0.05) higher oleic acid (18:1w9), total monounsaturated fatty acids, and total omega-9 fatty acids. Differences reported are highly attributable to variability in diet, although differences in fatty acid synthesizing pathways and hormonal influences may also play a role. This novel fatty acid data set in healthy flamingos is a valuable reference for complete health evaluations in managed care settings. Further comparisons with controlled diets and inclusion of free-ranging animals may enhance clinical utility.

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The magnificent frigatebird (Fregata magnificens; MFB) is a widely distributed seabird. It has breeding areas in the tropical Atlantic Ocean and the Pacific Ocean (extending along Central America up to Baja California) (Schreiber & Burger, 2001). The Fregata magnificens magnificens (MFB-Gal) subspecies is native to the Galápagos Islands. This is the first-time hematology and blood chemistry parameters have been published for the F. m. magnificens (MFB-Gal) from the Galápagos Islands. Analysis was run on blood samples drawn from n = 16 adult MFB-Gal captured by hand at their nests at North Seymour and Daphne Major Islands in the Galápagos Islands (n = 10 MFB-Gal in June 2017 and n = 6 MFB-Gal in July 2022). There were ten female birds and six male birds in total. A portable blood analyzer (iSTAT) was used to obtain near immediate field results for total carbon dioxide (TCO2), hematocrit (Hct), hemoglobin (Hb), sodium (Na), potassium (K), chloride (Cl), ionized calcium (iCa), total protein (TP), anion gap and glucose. Blood lactate was measured using a portable Lactate Plus™ analyzer. Average heart rate, respiratory rate, body weight, body temperature, biochemistry and hematology parameters were comparable to healthy individuals of other Fregatidae of the same species (magnificent frigatebird subspecies from Brazil, Fregata magnificens, likely F. m. rothschildi) or similar species (great frigatebird, Fregata minor, from the Galápagos Islands). There were some statistically significant differences between the males and females F. m. magnificens (MFB-Gal) in the Galápagos, including bill depth, bill width, wing length, weight, and chloride blood value. The reported results provide baseline data that can be used for comparisons among populations and in detecting changes in health status among Galápagos magnificent frigatebirds and other populations of magnificent frigatebirds.

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Abstract Introduction: Aquatic birds (AB) are usually associated with wetlands, which provide refuge, food, and/or nesting sites for resident and migratory species. Despite their ecological importance, there is little knowledge on AB in some tropical environments, such as those found on the Colima coast. Objective: To investigate the spatial and temporal composition of the AB community in Juluapan Lagoon, Colima, Central Mexican Pacific. Methods: Monthly counts were conducted between June 2017 and May 2018 during low-tide conditions to record habitat use by AB. Species richness and bird counts were obtained to compare sampling areas; mean richness and number of individuals were compared between seasons. Results: We detected 53 species and 5 750 individuals. The highest species richness and relative abundance values were obtained in winter at the lagoon area farthest from the connection with the marine system, where anthropogenic activity is lower. Diversity was greater in zones 2 and 3 in spring, summer, and fall. Muddy flats were the most used environment, and the most frequent activity was resting. Nesting activity was only recorded in the middle of the lagoon at the mangrove during spring. "Shorebirds" and "waders" were the most dominant groups in the bird community of the Juluapan lagoon. Conclusions: This coastal wetland is a site of great biological importance for aquatic birds; thus, conservation measures should be implemented, and there should be a continuous study of the effects of anthropogenic pressure.

Resumen Introducción: Las aves acuáticas (AA) son usualmente relacionadas a los humedales debido a que éstos funcionan como sitios de refugio, alimentación y anidación de diferentes especies residentes y migratorias. Sin embargo, el conocimiento sobre las aves acuáticas en algunos humedales es nulo. Objetivo: Investigar la composición espacio-temporal de la comunidad de AA en la laguna Juluapan, Colima, en el Pacífico Central Mexicano. Métodos: Entre junio de 2017 y mayo de 2018 se llevaron a cabo conteos mensuales en condiciones de marea baja para registrar el uso de hábitat de las AA. Se obtuvieron valores de riqueza de especies y número de individuos para realizar comparaciones entre zonas de muestreo, así como el promedio del número de especies y número de individuos para comparaciones entre temporadas. Resultados: Se registraron un total de 53 especies y 5 750 individuos. Los valores de riqueza de especies y densidad de individuos fueron más altos durante invierno, en la zona más alejada al ambiente marino, donde la actividad antropogénica es menor. La diversidad tuvo valores más altos en la zona 2 y 3, durante primavera, verano y otoño. El ambiente más explotado por las aves fueron las planicies lodosas; y el descanso fue la actividad más frecuente. Asimismo, la actividad de anidación sólo se registró en el manglar de la zona media durante primavera. Las "aves playeras" y "aves zancudas" fueron los grupos más predominantes en la comunidad de aves de la laguna Juluapan. Conclusiones: Este humedal costero es un sitio de gran importancia biológica para aves acuáticas, por lo que resulta necesario la implementación de medidas de conservación, así como el estudio de los efectos por la presión antropogénica.

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Abstract Introduction: A recent revision of the generic classification of the Trochilidae based on DNA sequences revealed many inconsistencies with the current generic classification, largely based on plumage characters subject to homoplasy, especially in the Trochilini, the largest tribe. A thorough generic reorganization brought the classification into accord with the phylogeny, but due to lack of genetic data, two species remained unclassified. One of these was the Mangrove Hummingbird, "Amazilia" boucardi, endemic to Costa Rica and included in the IUCN red list of threatened species. Objective: To obtain molecular evidence to clarify the generic relationships of "A." boucardi. Methods: We isolated DNA from tissues of this species and amplified 4 nuclear and 4 mitochondrial fragments and compared these with homologous fragments from 56 species in the Trochilini, constructing phylogenetic trees with maximum likelihood and Bayesian methods. Results: Our phylogenetic analyses confirmed the placement of boucardi in the Trochilini and definitely excluded it from Amazilia but placed it with high confidence in the genus Chrysuronia Bonaparte, 1850, within which its closest relative is C. coeruleogularis, which also inhabits mangroves. Conclusions: Our genetic data based on nuclear and mitochondrial regions clearly indicate the relationship of A. boucardi and L. coeruleogularis. Moreover, it is also supported by their habitat distribution in the mangroves of the Pacific coast of Costa Rica and Western Panama. Therefore, we suggested to exclude A. boucardi as "incertae sedis".

Resumen Introducción: Una revisión reciente de la clasificación de la familia Trochilidae con base en secuencias de ADN demostró muchas incongruencias con la clasificación genérica previa, que había sido hecho con base en caracteres del plumaje muy sujetos a homoplasia, especialmente en la tribu más grande, Trochillini. Una reorganización de los géneros logró llevar su clasificación genérica a la concordancia con la filogenia, pero debido a la ausencia de datos genéticos, dos especies permanecieron sin clasificar. Una de estas fue el colibrí de manglar Amazilia boucardi, una especie endémica de Costa Rica, considerada como amenazada en la lista roja de la UICN. Objetivo: Obtener evidencia molecular para esclarecer las relaciones genéricas de A. boucardi. Métodos: Se aisló ADN de tejidos de esta especie y se amplificaron 4 fragmentos de ADN del núcleo y 5 de la mitocondria, y se compararon con fragmentos homólogos de 56 especies en la tribu Trochillini, generando árboles filogenéticos con métodos de máxima verosimilitud y bayesiano. Resultados: Los análisis filogénticos obtenidos confirmaron la ubicación de boucardi en Trochilini y definitivamente la excluyó del género Amazilia, pero la ubicó con un alto grado de confianza en el género Chrysuronia Bonaparte, 1850, dentro los cuales su pariente más cercano es C. coeruleogularis, que también habita manglares. Conclusiones: Nuestros datos genéticos basados en regiones nucleares y mitocondriales indican claramente la relación entre A. boucardi and L. coeruleogularis. Es más, lo anterior se sustenta por su distribución en los manglares de la costa Pacífica de Costa Rica y oeste de Panamá. Por lo tanto, sugerimos excluir a A. boucardi como "incertae sedis".

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Resumen Introducción: Cada vez son más los estudios que incluyen la diversidad funcional para comprender los patrones de la biodiversidad. Sin embargo, en el departamento del Tolima, se ha investigado poco este aspecto en las comunidades de aves, lo que crea un vacío de conocimiento acerca de esta faceta de la diversidad biológica. Objetivo: Determinar cambios o patrones en la diversidad taxonómica y funcional de la avifauna del Centro Universitario Regional del Norte del Tolima (CURDN) durante un periodo de ocho años. Métodos: Los datos fueron organizados de manera que permitieran determinar cambios en la comunidad de aves a lo largo del tiempo y en diferentes épocas climáticas (alta y baja precipitación). Se emplearon diferentes índices de diversidad taxonómica y funcional (alfa y beta). Para evaluar el efecto de las temporadas climáticas y establecer diferencias entre los años, se utilizó el Escalamiento Multidimensional No Métrico (NMDS) y el Análisis de Similitud no paramétrico (ANOSIM). Resultados: Durante el periodo de estudio, se registraron 2 691 individuos. No se encontraron diferencias en la diversidad alfa, tanto taxonómica como funcional. Sin embargo, los resultados de estas dos facetas de la biodiversidad revelaron patrones opuestos que están estructurando la comunidad de aves. El análisis de partición de la diversidad taxonómica beta reveló un proceso de recambio de especies, mientras que la diversidad beta funcional determinó un anidamiento funcional. Conclusión: La diversidad funcional señaló la posibilidad de que las actividades antropogénicas llevadas a cabo en el CURDN actúan como filtros que estructuran la comunidad de aves. Estos hallazgos resaltan la importancia de considerar estas dos facetas de la biodiversidad para determinar cambios o patrones de las comunidades de aves durante un amplio periodo de estudio.

Abstract Introduction: More and more studies include functional diversity to understand biodiversity patterns. However, in Tolima department, little research has been conducted on this aspect in bird communities, creating a knowledge gap to this important facet of biodiversity. Objective: To determine changes or patterns in the taxonomic and functional diversity of bird communities at the Centro Universitario Regional del Norte (CURDN) for eight years. Methods: The data were organized to identify changes in the bird community over time and during different climatic periods (high and low precipitation). Several indices of taxonomic and functional diversity (alpha and beta) were used. Non-Metric Multidimensional Scaling (NMDS) and Non-Parametric Analysis of Similarity (ANOSIM) were applied to evaluate the impact of climatic periods and temporal variation. Results: During the sampling, 2 691 individuals were recorded. We found that there was no difference in the taxonomic and functional alpha diversity. However, the results of these two facets of biodiversity revealed opposing patterns that are structuring bird communities. The partitioning analysis of taxonomic beta diversity revealed a process of species turnover, while functional beta diversity revealed functional nestedness. Conclusions: Functional diversity suggested that anthropogenic activities in the CURDN act as filters that structure bird communities. These findings highlight the importance of considering these two facets of biodiversity to determine changes or patterns in bird communities over a long period.

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Abstract Introduction: Levee forests exhibit a vertical stratification that may contribute to structural complexity allowing a great diversity of birds to thrive on the islands. In deltaic ecosystems there is scarce or no data to prove it. Objectives: To assess variations in the composition of the bird community within levee forests. Methods: Two areas of protected wetlands belonging to the Paraná River Delta in Argentina were sampled for three years. A comparative analysis of richness, abundance, and diversity was performed in different levee forests using the point count method. Results: Three distinct types of levee forests -open, intermediate, and closed- were identified based on the structure of their vegetation, hosting a total of 85 bird species. Variation in avian community structure among forest types revealed greater diversity in open forests during winter (3.26 ± 0.13, P < 0.01) and spring (3.58 ± 0.05, P < 0.01), and greater richness in autumn (35.33 ± 3.01, P < 0.01). The closed forests exhibited increased diversity during autumn (3.16 ± 0.13, P < 0.05) and summer (3.24 ± 0.06, P < 0.05), along with elevated abundance in autumn (114 ± 13.70, P < 0.05) and richness in spring (39.17 ± 4.71, P = 0.01). Due to the evolutionary history between sites, significant variation was observed in the most recently created national park, influencing abundance in winter (141 ± 22.06, P < 0.01) and spring (176 ± 12.83, P < 0.01), as well as diversity in winter (3.25 ± 0.10, P < 0.01) and spring (3.50 ± 0.10, P < 0.01). Conclusions: The microhabitat in the different levee forests allows the birds to organize differently. Focusing on microspatial dynamics is key to a deep understanding of the biological processes within subtropical islands and to plan conservation strategies and demonstrate the transition of a recovering riparian forest towards its natural state, where the pulse of the river and the effect of seasonality do not stop operating.

Resumen Introducción: Los bosques de albardón exhiben una estratificación vertical que puede contribuir en la complejidad estructural, permitiendo que una gran diversidad de aves prospere en las islas. En ecosistemas deltaicos hay escasos datos que lo demuestren. Objetivos: Evaluar las variaciones en la composición de la comunidad de aves dentro de los bosques de albardón. Método: Se muestrearon durante tres años, dos áreas protegidas de humedales pertenecientes al Delta del Río Paraná, Argentina. Se realizó un análisis comparativo de riqueza, abundancia y diversidad de aves en tres diferentes bosques de albardón, utilizando el método de conteo por puntos. Resultados: Tres distintos tipos de bosque de albardón -abiertos, intermedios y cerrados- fueron identificados con base en la estructura de su vegetación, hospedando un total de 85 especies de aves. La variación en la estructura de la comunidad de aves entre tipos de bosque revela mayor diversidad en bosques abiertos durante el invierno (3.26 ± 0.13, P < 0.01) y la primavera (3.58 ± 0.05, P < 0.01), y mayor riqueza en otoño (35.33 ± 3.01, P < 0.01). Los bosques cerrados exhibieron mayor diversidad en el otoño (3.16 ± 0.13, P < 0.05) y en verano (3.24 ± 0.06, P < 0.05), junto con elevada abundancia en otoño (114 ± 13.70, P < 0.05) y elevada riqueza en primavera (39.17 ± 4.71, P=0.01). Debido a la historia evolutiva entre sitios, se observó variación significativa en el parque nacional de más reciente creación, influyendo en la abundancia del invierno (141 ± 22.06, P < 0.01) y de la primavera (176 ± 12.83, P < 0.01), así como en la diversidad en el invierno (3.25 ± 0.10, P < 0.01) y en la primavera (3.50 ± 0.10, P < 0.01). Conclusiones: El microhábitat en los diferentes bosques de albardón permite a las aves organizarse diferencialmente. Enfocarse en la dinámica microespacial es clave para una comprensión profunda de los procesos biológicos dentro de las islas subtropicales, planificar estrategias de conservación y evidenciar la transición de un bosque ripario en recuperación hacia su estado natural, donde el pulso del río y el efecto de la estacionalidad no dejan de operar.

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Ocean pollution by plastics is a growing concern for marine wildlife conservation, and seabirds are particularly prone to ingest plastics. We report baseline information on plastic ingestion in 17 procellariiform species along the coast of Brazil and Argentina. Through a collaborative regional effort we found plastic items in 30.2 % of seabird carcasses examined (n = 192), comprised predominantly by mesoplastics (5-25 mm), user plastics, polypropylene, polystyrene and polyethylene. Considering the most representative source-site cohorts, the frequency of occurrence of plastic items varied significantly between sampling site and source of carcasses. Ingestion was highest in petrels and shearwaters. Immature birds ingested the largest number (and total mass) of plastic items followed by chicks and adults. Long-term programs applying standardized sampling protocols are needed to detect spatiotemporal patterns of plastic ingestion across species, and assess the potential effectiveness of remediation actions. Further studies are necessary to assess currently unrecognized health effects of plastic ingestion.

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Tropical biodiversity is undergoing unprecedented changes due to the hydrological cycle intensification, characterized by more intense droughts and wet seasons. This raises concerns about the resilience of animal and plant communities to such extremes and the existence of potential refugia-areas theorized to safeguard biological communities from adverse climate impacts. Over 20 years of monitoring in Central Amazonia, we investigated the short-term and long-term effects of hydrological cycle intensification on bird, fish, ant, and palm communities. We explored whether the 'insurance effect' of climate trends (droughts buffered by preceded wet seasons) or 'environmental refugia' (droughts or floods buffered by topographic features) could lessen the impact of climate events on community composition, richness, evenness, and species rank. Pronounced abundance changes were observed among animal species, whereas palm species showed relative temporal stability. Birds and fish were more affected by the immediate and long-term severity of droughts and wet periods, while ants responded primarily to short-term drought impacts. Conversely, palm communities exhibited delayed responses to climate extremes, primarily in long-term comparisons. As expected, the proposed 'insurance effect' mitigates the long-term impacts of extreme climate events on animal and plant community trends. However, less extreme hydrological conditions linked to topographic features did not provide effective 'environmental refugia' for animals or plants during adverse climate conditions. These outcomes underscore the complex and varied biological responses to ongoing climate change, challenging the prevailing assumptions about the efficacy of environmental refugia and highlighting the nuanced resilience of biodiversity in Central Amazonia.

A biodiversidade tropical está passando por mudanças sem precedentes devido à intensificação do ciclo hidrológico, caracterizada por secas mais intensas e estações chuvosas mais severas. Isso gera preocupações sobre a resiliência das comunidades de animais e plantas a esses extremos e a existência de potenciais refúgios ­ áreas teoricamente capazes de proteger as comunidades biológicas dos impactos climáticos adversos. Em mais de 20 anos de monitoramento na Amazônia Central, investigamos os efeitos de curto e longo prazo da intensificação do ciclo hidrológico sobre as comunidades de aves, peixes, formigas e palmeiras. Exploramos se o 'efeito seguro' das tendências climáticas (secas amortecidas por estações chuvosas precedentes) ou 'refúgios ambientais' (secas ou cheias amortecidas por características topográficas) poderiam atenuar o impacto dos eventos climáticos na composição das comunidades, riqueza, equidade e mudança na abundância das espécies. Mudanças pronunciadas na abundância foram observadas entre as espécies animais, enquanto as palmeiras apresentaram relativa estabilidade temporal. Aves e peixes foram mais afetados pela severidade imediata e de longo prazo das secas e períodos chuvosos, enquanto as formigas responderam principalmente aos impactos de secas de curto prazo. Em contrapartida, as palmeiras mostraram respostas atrasadas aos extremos climáticos, principalmente em comparações de longo prazo. Como esperado, o 'efeito seguro' proposto atenua os impactos de longo prazo de eventos climáticos extremos nas tendências das comunidades de animais e plantas. No entanto, condições hidrológicas menos extremas associadas a características topográficas não forneceram refúgios ambientais efetivos para animais ou plantas durante condições climáticas adversas. Esses resultados destacam as respostas biológicas complexas e variadas às mudanças climáticas em curso, desafiando as suposições predominantes sobre a eficácia dos refúgios ambientais e ressaltando a resiliência sutil da biodiversidade na Amazônia Central.

RESUMO

Ascaridoidea (Nematoda) is a widespread superfamily of nematodes that comprises gastrointestinal parasites from all major groups of vertebrates. Although this taxon probably emerged in the Carboniferous, its Brazilian fossil record includes mostly eggs, found in ancient remains, collected in paleontological and archeological sites from the Mesozoic and Cenozoic Eras. The Tremembé Formation (Oligocene of the Taubaté Basin) has become an important source for paleoparasitological studies in avian coprolites during the third decade of the 21st century, with reports of eggs only at only a single cell stage, of embryonic development. Here we present the first egg of Ascaridoidea preserved containing morula, from a bird coprolite recovered from the shales of the Tremembé Formation. Three coprolites, from the outcrop of Aligra Comércio de Argila S/A, Taubaté municipality (State of São Paulo), were rehydrated and subjected to spontaneous sedimentation. Based on morphological and morphometric features and diet and zoopaleontological context, the trace fossils were assigned to piscivorous birds. The egg found showed morphological characteristics typical of Ascaridoidea: namely spherical form, ornamented, and somewhat thick shell. Moreover, this superfamily includes several taxa that infect piscivorous birds and fish in heteroxenous life cycles and produce eggs with similar features as the egg found in the present study. The paleoparasitological information associated with the paleofaunistic diversity of birds and fish from the Tremembé Formation, reveal that the ancient Brazilian paleoenvironments provided subsidies for the rise and success of nematodes infecting these animals during the Paleogene.