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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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BACKGROUND: Brazil has one of the planet's greatest biodiversity, with over 20% of the world's total species. The Brazilian Atlantic Forest (BAF) spans 17 Brazilian states, making it the third-largest biome in Brazil. The BAF is composed of a range of ecological formations, with climatic conditions and landscape diversity that directly contribute to the different structures of the forest. The fragmentation of the original habitats, mainly due to anthropogenic activities, is one of the main causes of biodiversity loss, causing the decline and habitat loss for several species, including birds and mammals. While there has been extensive research on species diversity in forest fragments or protected areas, there is a lack of basic research in agricultural ecosystems. Only 1.5% of the studies on bird occurrence data in the BAF were reported from pasture habitats and 1.4% from exotic tree plantations. To address this gap, the present systematic map protocol aims to carry out a bibliographic survey on the presence of birds and mammals in agricultural landscapes and its adjacent areas of natural vegetation to describe the prevalence of species across different (semi-)natural and anthropogenic habitat types. Collecting this data is important to support environmental management policies to preserve biodiversity in these areas. METHODS: We will conduct a systematic literature review on the biodiversity of birds and mammals in agricultural landscapes within the Brazilian Atlantic Forest as well as adjacent areas of natural vegetation. Our search will cover the following databases, without limiting the year of publication: Web of Knowledge, Scopus, and PubMed. We will also include grey literature such as dissertations and theses, performing the search at the "Biblioteca Digital Brasileira" database. The results will be screened for relevance based on predefined criteria. The screening process will take place in two stages: firstly, the articles will be screened by title and abstract, and then the eligible articles will be screened in full text. Only articles that meet the eligibility criteria will proceed to data extraction. The extracted data will provide the elements to build a systematic map.

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Citizen science data on biodiversity has experienced significant growth, largely driven by advancements in technology that facilitate data sharing. In recent years, mobile applications have provided a substantial boost to both the collection and sharing of this data. While this accessible information is undoubtedly valuable, we must consider the numerous biases present in this data when used for high-quality research. In this study, we analyse citizen science data for the birds of the Iberian Peninsula, comprising over 23 million unique records after filtering for duplicates (i.e., instances where the same observation was uploaded more than once). Using a 10 × 10 km square grid, we present information on well-surveyed cells (completeness) as well as temporal, taxonomic, geographical, and land use coverages. We found that the completeness of information is generally high, with better coverage around densely populated areas such as major cities and coastal regions, as well as popular birding destinations, which are frequently visited. The Mediterranean ecoregion and wetlands exhibit the highest levels of surveying. Furthermore, we observed an increase in temporal coverage since the 1980s and broad taxonomic coverage across all bird orders in the Iberian region. Our results underscore the utility of citizen science for many locations, as expressed in 10 × 10 km cells. However, they also highlight the inadequate data completeness across part of the territory, particularly in forested or sparsely inhabited areas. These findings not only identify cells suitable for bird diversity or conservation studies but also indicate areas where citizen-driven bird recording efforts should be encouraged.

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The Pedregal de San Ángel Ecological Reserve (REPSA) is located within the central campus of the National Autonomous University of Mexico (UNAM), in southwestern Mexico City. This area is known for its bird richness, which has been documented over time. However, this historical information has not been compiled, nor has it been assessed whether species composition has changed over time. In this study, we generated the historical checklist of avifauna in the REPSA by integrating data from systematic monitoring, bibliographic review and citizen science. Additionally, we calculated Jaccard's dissimilarity Index (nestedness and species turnover) among bird checklists from each year and evaluated whether this index and its components changed over time. In addition, we estimate whether the proportion of species arriving and becoming extinct in the REPSA is influenced by time (census interval) and by the migratory status of the species. Finally, we identified the core species of the REPSA. Our results indicate that from 1967 to 2023, 258 bird species have been recorded in the REPSA. The Jaccard's dissimilarity and turnover increased and reached an asymptotic trend over time while nestedness showed similar values throughout time. The time and species residency status did not have significant effect on the proportion of species that arrival and become extinct in the reserve. We identified 58 core species based on their persistence; 35 of these are residents, 22 have some migratory movement and one exotic species. Our results highlight the importance of the REPSA as a fundamental habitat for the avifauna of Mexico City, including a wide variety of migratory bird species.

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Studying parasites in captive wild birds is vital for their health, well-being, biodiversity preservation, species conservation, and safeguarding of both individual birds and ecosystems. It holds significance for public health by identifying potential zoonotic risks. We aimed to describe the occurrence of gastrointestinal parasites in captive wild birds from a Conservation Institute in Brazilian Cerrado biome. Fresh fecal samples were collected from 17 captive wild birds (Anodorhynchus hyacinthinus, Ara ararauna, Ara chloropterus, Ara macao, Megascops choliba, Pteroglossus castanotis, Ramphastos dicolorus, Ramphastos tucanus and Strix huhula) at a Conservation Institution in Mineiros, state of Goiás. The samples were processed for Willis' simple flotation and Hoffman's spontaneous sedimentation examinations to identify parasitic forms of gastrointestinal endoparasites. Macaw aviary birds (Ar. ararauna, Ar. chloropterus and Ar. macao) showed higher positivity, with all six fecal samples positive for helminths or protozoa. In contrast, captive toucans showed only two positive results (P. castanotis and R. dicolorus). An. hyacinthinus showed Ascarididae, Capillarinae and Trematoda eggs; whereas S. huhula had Ascarididae eggs. Regular parasitological examinations are essential for the timely detection and treatment of gastrointestinal infections in captive birds, thereby enhancing overall bird management.

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Since 2019, the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) has actively developed pesticide environmental risk assessment (ERA) frameworks adapted to Brazil's specific ecological contexts. This initiative, supported by funding from the Brazilian Ministry of Justice and in partnership with academic institutions, has led to a concerted effort to establish ERA protocols for various taxa, including birds and mammals, soil organisms, aquatic organisms, and reptiles and amphibians. The outcomes of this initiative were disseminated in two distinct workshops held in February and November of 2023, where the agency showcased its research to the technical-regulatory community. This article synthesizes the proposals for birds and mammals and soil organisms. First, we summarize the agency's proposals for both focal and generic species to be incorporated into the ERA and the methodologies for calculating exposure of these taxa to pesticides through agricultural practices, encompassing seed treatment and foliar applications. On this occasion, IBAMA also disclosed the risk assessment tool that the agency is developing for birds and mammals. IBAMA highlighted the knowledge gaps that must be bridged to progress from preliminary (lower-tier) to more comprehensive (higher-tier) assessments. Regarding soil organisms, during the workshop, the presenters shared findings on the most prevalent species of earthworms and enchytraeids in Brazil. They emphasized the need for additional data collection on a regional scale. The agency has also proposed methods for estimating soil organism exposure to pesticides at a screening level and identified specific data gaps that could be addressed to refine assessments at higher tiers. In summary, the workshop communicated the progress in establishing ERA guidelines, which we encapsulate here to benefit the technical-regulatory community. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

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With the expansion of green energy, more and more data show that wind turbines can pose a significant threat to some endangered bird species. The birds of prey are more frequently exposed to collision risk with the wind turbine blades due to their unique flight path patterns. This paper shows how data from a stereovision system can be used for an efficient classification of detected objects. A method for distinguishing endangered birds from common birds and other flying objects has been developed and tested. The research focused on the selection of a suitable feature extraction methodology. Both motion and visual features are extracted from the Bioseco BPS system and retested using a correlation-based and a wrapper-type approach with genetic algorithms (GAs). With optimal features and fine-tuned classifiers, birds can be distinguished from aeroplanes with a 98.6% recall and 97% accuracy, whereas endangered birds are delimited from common ones with 93.5% recall and 77.2% accuracy.

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Abstract: In the city of Temuco, Chile, the importance of urban wetlands has been recognized with the legal declaration of two key ecosystems: Humedal Vegas de Chivilcán and Humedales de Antumalén. This paper presents an inventory of birds in these wetlands, following the Darwin Core standard, and compares the results with other selected inventories in Chile. Observations were made using point counts and 21-hour transects. A total of 50 species from 26 families and 15 orders were identified, with a predominance of native species. Fourteen species were found in both wetlands, 20 exclusively in Chivilcán and 15 in Antumalén. Comparison with other studies revealed significant differences in bird composition between urban and peri-urban habitats, illustrating that urban habitats maintain a unique diversity distinct from that of peri-urban areas. The diversity of habitats and the 'least concern' status of most species highlight the importance of these wetlands as refuges for avian biodiversity. The structure of the Darwin Core database facilitates their integration with other biodiversity systems, highlighting the need for continued conservation and study of these urban ecosystems.

Resumen: En la ciudad de Temuco, Chile, se ha reconocido la importancia de los humedales urbanos con la declaración de dos ecosistemas clave: Humedal Vegas de Chivilcán y Humedales de Antumalén. Este trabajo presenta un inventario de aves en estos humedales, siguiendo la norma Darwin Core, y compara los hallazgos con otros inventarios seleccionados en Chile. Las observaciones se realizaron mediante conteos puntuales y transectos durante 21 horas. Se identificaron un total de 50 especies de 26 familias y 15 órdenes, predominando las especies nativas. Catorce especies se encontraron en ambos humedales, 20 eran exclusivas de Chivilcán y 15 de Antumalén. La comparación con otros estudios reveló diferencias significativas en la composición de aves entre hábitats urbanos y periurbanos, mostrando que los hábitats asociados a ciudades mantienen una diversidad singular que difiere de los hábitats periurbanos. La diversidad de hábitats y el estatus de "preocupación menor" de la mayoría de las especies resaltan la importancia de estos humedales como refugios para la biodiversidad aviar. La estructura de la base de datos Darwin Core facilita su integración con otros sistemas de biodiversidad, subrayando la necesidad de continuar con la conservación y el estudio de estos ecosistemas urbanos.

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Introducción: La presencia y estructura de la vegetación en áreas urbanas tiene un impacto en la composición de las comunidades de aves. Las áreas verdes con una mayor proporción de vegetación introducida tienden a presentar una homogeneización de avifauna, mientras que las áreas verdes con alta proporción de vegetación nativa presentan mayor diversidad de aves. En varios trabajos realizados en áreas urbanas de México, estos factores no son tomados en cuenta. Por lo tanto, se desconocen las respuestas de las especies en términos de riqueza y diversidad. Objetivo: Analizar la composición de especies de aves en las áreas verdes de Ciudad Victoria, Tamaulipas y evaluar la respuesta de las comunidades de aves en tres áreas verdes con diferente composición de vegetación. Así como analizar la relación entre los gremios tróficos de aves con los elementos de la vegetación en las áreas urbanas. Métodos: El estudio se llevó a cabo en tres sitios de muestreo de Ciudad Victoria, Tamaulipas, México, con base en dos criterios: área similar de muestreo (ha) y diferencias en las características de la vegetación. Los monitoreos se realizaron de enero a diciembre de 2020, con tres visitas mensuales en cada sitio para un total de 108 visitas, utilizando el método visual directo. Resultados: Identificamos 98 especies (11 órdenes, 28 familias). Las especies más abundantes fueron Quiscalus mexicanus y Molothrus aeneus. Hubo diferencias en la riqueza de especies para cada sitio. Las insectívoras y granívoras fueron las dominantes. Se determinó una asociación entre los gremios y los sitios de estudio, donde la mayoría están relacionados con la vegetación mixta, comparado con la vegetación homogénea o introducida. Conclusiones: Las áreas urbanas estudiadas mantuvieron un número notable de aves, y varias de ellas presentaron alguna categoría de riesgo o endemismo. Esto demuestra la importancia de estas áreas verdes como refugio de aves y resalta la necesidad de conservar y proteger dichas áreas dentro de Ciudad Victoria y ciudades similares.

Introduction: The presence and structure of vegetation in urban areas have an impact on the composition of bird communities. Green areas with a higher ratio of introduced vegetation tend to have a greater homogenization of avifauna, whereas green areas with a high ratio of native vegetation have a greater diversity of birds. In several studies carried out in urban areas of Mexico, the factors of vegetation are not considered. Therefore, the responses of the species to vegetation types in terms of richness and diversity are unknown. Objective: To analyze the composition of bird species in the green areas of Ciudad Victoria, Tamaulipas, and evaluate the response of bird communities in areas with differences in vegetation composition. As well as to analyze the relationship between the trophic guilds in birds and vegetation in urban areas. Methods: Three sampling sites were established in Ciudad Victoria, Tamaulipas, Mexico, based on two criteria: similar sampling area (ha) and differences in vegetation characteristics. Monitoring took place between January and December 2020, with three monthly visits in each site for a total of 108 visits, using the direct visual method. Results: We identified 98 species (11 orders, 28 families). The most abundant species were Quiscalus mexicanus and Molothrus aeneus. Differences in species richness were found for each site. The insectivorous and granivorous were the dominant guilds. An association between the guilds and the study sites was determined, where most were linked to mixed native vegetation, compared to homogeneous or introduced vegetation. Conclusions: The urban areas studied maintained a notable number of birds, and several of them presented some category of risk or endemism. This demonstrates the importance of these green areas composed of native vegetation as a refuge for birds and highlights the need to conserve and protect these areas within Ciudad Victoria and similar cities.

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For the study on the relationships between the seed dispersal of exotic plants and bird population, flora, avifauna, vegetation patches, and the dynamics of seed banks were investigated in and around the exposed floodplains of the large rivers, and the causes of exotic vegetation development were determined with respect to plant life form, bird population characteristics, and landscape using multivariate analysis. The number of dominant exotic plant species observed in exposed areas was higher than that observed in an abandoned field and paddy field undergoing secondary succession. Additionally, the area occupied by exotic vegetation in exposed areas increased with the increase in number of vine plants and small terrestrial birds, whereas the relationship between vine and runner plants was inversely proportional. Therefore, to control exotic plants in exposed floodplains surrounding large rivers, it is necessary to remove vines and shrubs along the waterfront where small resident birds carrying plant seeds live and to maintain and manage runner plant populations. Furthermore, implementing an ecological landscape management strategy, such as afforestation through the planting of trees, may also be effective.

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Habitat heterogeneity is a key driver of the diversity and distribution of species. African savannas are experiencing changes in their vegetation structure causing shifts towards increased woody plant cover, which results in vegetation structure homogenization. Given the impact that increasing woody plant cover has on patterns of animal use, resource managers across Africa are implementing habitat management practices that are intended to reduce woody plant cover. To understand the ecological implications of various habitat management practices on arthropod and bird communities, we leveraged large-scale tree clearing and subsequent mowing in an African savanna to understand how changes in both the herbaceous layer and woody plant cover (i.e., structural heterogeneity) may shape arthropod and bird communities at the local scale. We focused on four replicated treatments: (1) annual summer mow, (2) annual winter mow, (3) >5 years since last mow (rest), and (4) an adjacent unmanipulated savanna to act as a control. We found that the mowing treatments significantly influenced vegetation structure both with respect to tree density and herbaceous layer. Both arthropod and bird community composition varied across treatments. Grass biomass was the best predictor of arthropod richness and abundance, with arthropods selecting for areas with high biomass. Insectivorous bird richness and abundance was driven by tree density (i.e., perching locations) and not arthropod abundance. Our results suggest that vegetation management practices contribute to habitat heterogeneity at the landscape scale and increase bird species richness through species turnover. However, we caution that if a single vegetation management practice dominates the landscape, it is plausible that it could lead to the simplification of the avian community.

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Members of Enterobacteriaceae are known to produce extended-spectrum beta-lactamases (ESBL) which hydrolyze the beta-lactam group of antibiotics. The existence of ESBL-producing Salmonella enterica (S. enterica) and Escherichia coli (E. coli) harbored by urban avifauna was investigated in this study. Dropping samples (n= 180) were collected from six different bird species in the district Jhang, Punjab province, Pakistan. Isolation and identification of ESBL isolates were made by using cefotaxime- (4 mg/L) supplemented MacConkey agar and double disc synergy test (DDST). Polymerase chain reaction (PCR) was performed for the detection of four different ESBL genes including blaCTX-M, blaTEM, blaSHV and blaOXA. A total of 42.69% isolates were confirmed as ESBL via DDST including 30.64% S. enterica and 49.54% E. coli. The incidence of ESBL S. enterica and ESBL E. coli was found highest in egret (Ardea alba) and pigeon (Columba livia) as 64.28% and 78.95%, respectively. The blaCTX-M gene was detected in 57.89% and 64.81% of isolates of S. enterica and E. coli, respectively. Among other genes in S. enterica and E. coli, blaTEM (21.05%, 20.4%); blaSHV (15.78%, 9.26%), and blaOXA (5.26%, 5.56%) were detected, respectively. All of the tested isolates were found resistant to at least one of the thirteen antimicrobial agents except meropenem. To the best of our knowledge, this is the first study reporting the incidence and genetic diversity of ESBL bacteria associated with urban avifauna in Pakistan. The urban avifauna can serve as a potential subject of bio-surveillance to monitor the emergence of antimicrobial-resistant bacteria.

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Background: Tea plantations support regional sustainable development and have the potential to support more biodiversity than urban open spaces. Numerous studies have shown the value of low-intensity agroecosystems for preserving biodiversity, however tea plantations have received less attention. The relationship between tea plantations and the diversity of macro-organisms, such as birds, is still not fully understood. Methods: We investigated the bird diversity and vegetation conditions and calculated landscape metrics in 30 tea plantations in Anji County, Zhejiang Province, China. At these 30 sampling sites, we recorded 262 individuals belonging to 37 species, which were classified into two guilds: nature- and urban-dependent birds. We used cluster analysis to group the sampling sites based on the abundance of the birds. Then we evaluated the effects of associated plant diversity in tea plantations and the surrounding landscape composition on these bird guilds using species association computation and a generalized linear model. Results: The results show that the maintenance of bird diversity by tea plantations benefits both nature- and urban-dependent birds. We found that landscape-scale factors surrounding the tea plantations mainly affected the bird richness due to their habitat selection. Landscape agglomeration and habitat quality were the dominant landscape-scale metrics. Patch-scale factors of tea plantations, especially the vegetation structure, had a strong influence on the abundance of the birds. Nature-dependent birds preferred to occur in tea plantations with perennial herbs, while urban-dependent birds were attracted by the general distributed plants, as annual herbs. Therefore, we concluded that tea plantations play an important role as a transitional zone between natural habitats and urban areas, thus reducing the impact of urbanization and maintaining bird diversity in low-quality habitats.

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Environmentally Sensitive Areas (ESA) refer to areas that are of critical importance in terms of ecosystem services such as goods, services and life-support systems, such as water purification, pest control and erosion regulation. In addition, they also refer to areas that harbour the wealth of the nation's biodiversity. However, the classification of ESA in Malaysia is incomprehensible and lacks weightage on biological elements as the current classification is more centred on physical attributes. In order to enhance the existing classification of ESA by introducing biological elements, biological data are urgently required, especially for forest reserves and protected habitat. Hence, we conducted understorey birds surveys in three ESA rank II permanent forest reserves, located in northern Selangor as baseline information to strengthen the ESA classification. The surveys were carried out using mist-netting in three 400 m × 200 m plots. Alpha diversity indices were calculated and showed a significant difference in terms of diversity, composition and biomass of understorey birds between investigated sites. Analysis of similarity (ANOSIM) showed that bird assemblages from forest reserves designated as ESA rank II in Selangor, based on disturbances levels, have weakly diverged and SIMPER analysis has identified six species that contributed to 60% of the differences amongst the bird assemblages. The finding provides the first insight into understorey birds of the study sites and the importance of conserving and preserving ESA of permanent forest reserves, especially the small and fragmented forests.

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Acetylcholinesterase (AChE) activity levels can be used as an indicator for AChE inhibition due to pesticide poisoning in bird species. We assessed the comparative brain cholinesterase (AChE) activity level of five bird species inhabiting pesticide exposed croplands and Protected Area i.e. Deva Vatala National Park (DVNP), Bhimber by using a spectrophotometric method. AChE activity levels ranged from 56.3 to 85.9 µmol/min/g of brain tissue of birds representing DVNP. However, AChE activity levels ranged from 27.6 to 79.9 µmol/min/g of brain tissue of birds representing croplands. AChE activity levels observed in Jungle babbler, Common babbler, and Red-vented bulbul showed significant differences (P 0.05). Maximum inhibition was recorded in Jungle babbler (53%) followed by Common babbler (35%), Red-vented bulbul (18%), White wagtail (15%), and Black drongo (7%). The brain cholinesterase inhibition levels under-protected ecosystems (DVNP, Bhimber) and agricultural landscape suggest insecticidal contamination and its impact on avifauna diversity. The study also emphasizes on the importance of pesticide-free zones to protect the biodiversity of birds.

Os níveis de atividade da acetilcolinesterase (AChE) podem ser usados como um indicador para a inibição da AChE devido ao envenenamento por pesticidas em espécies de aves. Avaliamos o nível de atividade comparativa da colinesterase cerebral (AChE) de cinco espécies de aves que habitam áreas cultivadas expostas a pesticidas e Área Protegida, ou seja, Deva Vatala National Park (DVNP), Bhimber, usando um método espectrofotométrico. Os níveis de atividade da AChE variaram de 56,3 a 85,9 µmol / min / g de tecido cerebral de aves representando DVNP. No entanto, os níveis de atividade da AChE variaram de 27,6 a 79,9 µmol / min / g de tecido cerebral de aves representando áreas de cultivo. Os níveis de atividade de AChE observados no tagarela da selva, tagarela comum e bulbul vermelho exalado mostraram diferenças significativas (P 0,05). A inibição máxima foi registrada no tagarela da selva (53%), seguido pelo tagarela comum (35%), bulbul vermelho (18%), alvéola branca (15%) e drongo preto (7%). Os níveis de inibição da colinesterase cerebral nos ecossistemas subprotegidos (DVNP, Bhimber) e na paisagem agrícola sugerem contaminação por inseticida e seu impacto na diversidade da avifauna. O estudo também enfatiza a importância das zonas livres de pesticidas para proteger a biodiversidade das aves.

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Abstract Acetylcholinesterase (AChE) activity levels can be used as an indicator for AChE inhibition due to pesticide poisoning in bird species. We assessed the comparative brain cholinesterase (AChE) activity level of five bird species inhabiting pesticide exposed croplands and Protected Area i.e. Deva Vatala National Park (DVNP), Bhimber by using a spectrophotometric method. AChE activity levels ranged from 56.3 to 85.9 µmol/min/g of brain tissue of birds representing DVNP. However, AChE activity levels ranged from 27.6 to 79.9 µmol/min/g of brain tissue of birds representing croplands. AChE activity levels observed in Jungle babbler, Common babbler, and Red-vented bulbul showed significant differences (P 0.05) at two sites. However, White wagtail and Black drongo demonstrated non-significant differences (P > 0.05). Maximum inhibition was recorded in Jungle babbler (53%) followed by Common babbler (35%), Red-vented bulbul (18%), White wagtail (15%), and Black drongo (7%). The brain cholinesterase inhibition levels under-protected ecosystems (DVNP, Bhimber) and agricultural landscape suggest insecticidal contamination and its impact on avifauna diversity. The study also emphasizes on the importance of pesticide-free zones to protect the biodiversity of birds.

Resumo Os níveis de atividade da acetilcolinesterase (AChE) podem ser usados como um indicador para a inibição da AChE devido ao envenenamento por pesticidas em espécies de aves. Avaliamos o nível de atividade comparativa da colinesterase cerebral (AChE) de cinco espécies de aves que habitam áreas cultivadas expostas a pesticidas e Área Protegida, ou seja, Deva Vatala National Park (DVNP), Bhimber, usando um método espectrofotométrico. Os níveis de atividade da AChE variaram de 56,3 a 85,9 µmol / min / g de tecido cerebral de aves representando DVNP. No entanto, os níveis de atividade da AChE variaram de 27,6 a 79,9 µmol / min / g de tecido cerebral de aves representando áreas de cultivo. Os níveis de atividade de AChE observados no tagarela da selva, tagarela comum e bulbul vermelho exalado mostraram diferenças significativas (P 0,05) em dois locais. No entanto, alvéola branca e drongo preto demonstraram diferenças não significativas (P > 0,05). A inibição máxima foi registrada no tagarela da selva (53%), seguido pelo tagarela comum (35%), bulbul vermelho (18%), alvéola branca (15%) e drongo preto (7%). Os níveis de inibição da colinesterase cerebral nos ecossistemas subprotegidos (DVNP, Bhimber) e na paisagem agrícola sugerem contaminação por inseticida e seu impacto na diversidade da avifauna. O estudo também enfatiza a importância das zonas livres de pesticidas para proteger a biodiversidade das aves.

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Abstract Acetylcholinesterase (AChE) activity levels can be used as an indicator for AChE inhibition due to pesticide poisoning in bird species. We assessed the comparative brain cholinesterase (AChE) activity level of five bird species inhabiting pesticide exposed croplands and Protected Area i.e. Deva Vatala National Park (DVNP), Bhimber by using a spectrophotometric method. AChE activity levels ranged from 56.3 to 85.9 µmol/min/g of brain tissue of birds representing DVNP. However, AChE activity levels ranged from 27.6 to 79.9 µmol/min/g of brain tissue of birds representing croplands. AChE activity levels observed in Jungle babbler, Common babbler, and Red-vented bulbul showed significant differences (P < 0.05) at two sites. However, White wagtail and Black drongo demonstrated non-significant differences (P > 0.05). Maximum inhibition was recorded in Jungle babbler (53%) followed by Common babbler (35%), Red-vented bulbul (18%), White wagtail (15%), and Black drongo (7%). The brain cholinesterase inhibition levels under-protected ecosystems (DVNP, Bhimber) and agricultural landscape suggest insecticidal contamination and its impact on avifauna diversity. The study also emphasizes on the importance of pesticide-free zones to protect the biodiversity of birds.

Resumo Os níveis de atividade da acetilcolinesterase (AChE) podem ser usados ​​como um indicador para a inibição da AChE devido ao envenenamento por pesticidas em espécies de aves. Avaliamos o nível de atividade comparativa da colinesterase cerebral (AChE) de cinco espécies de aves que habitam áreas cultivadas expostas a pesticidas e Área Protegida, ou seja, Deva Vatala National Park (DVNP), Bhimber, usando um método espectrofotométrico. Os níveis de atividade da AChE variaram de 56,3 a 85,9 µmol / min / g de tecido cerebral de aves representando DVNP. No entanto, os níveis de atividade da AChE variaram de 27,6 a 79,9 µmol / min / g de tecido cerebral de aves representando áreas de cultivo. Os níveis de atividade de AChE observados no tagarela da selva, tagarela comum e bulbul vermelho exalado mostraram diferenças significativas (P < 0,05) em dois locais. No entanto, alvéola branca e drongo preto demonstraram diferenças não significativas (P > 0,05). A inibição máxima foi registrada no tagarela da selva (53%), seguido pelo tagarela comum (35%), bulbul vermelho (18%), alvéola branca (15%) e drongo preto (7%). Os níveis de inibição da colinesterase cerebral nos ecossistemas subprotegidos (DVNP, Bhimber) e na paisagem agrícola sugerem contaminação por inseticida e seu impacto na diversidade da avifauna. O estudo também enfatiza a importância das zonas livres de pesticidas para proteger a biodiversidade das aves.

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Resumen Introducción: México concentra alrededor del 11 % de las especies de aves del mundo, de las cuales el 20 % son endémicas del país, concentrándose el mayor número en la región occidental. Objetivo: Analizar la composición, diversidad y distribución de la avifauna a lo largo de un gradiente altitudinal en el occidente de México. Métodos: La investigación se realizó en la Reserva de la Biosfera Sierra de Manantlán. Registramos especies de aves vistas o escuchadas en 28 puntos de conteo fijos a lo largo de un gradiente de elevación de 1 000 m. La comparación de la riqueza y la completitud del muestreo se determinaron con curvas de interpolación y extrapolación. Las franjas se compararon con un Procedimiento no Paramétrico de Permutación Multirespuesta. Se usaron correlaciones y ordenaciones indirectas para analizar cambios en la riqueza y abundancia. Resultados: Registramos 129 especies (estimado: 96 % de completitud): 19 endémicas de México, 13 en alguna categoría de riesgo y 21 consideradas indicadoras. La elevación determinó la distribución y abundancia de las especies, y las franjas altitudinales más bajas, tuvieron los valores más altos de riqueza y abundancia. Conclusión: La mayor riqueza y abundancia de especies se registró a menor altitud, con un cambio significativo en la composición y tipo de especies indicadoras por franja.

Abstract Introduction: Mexico concentrates around 11 % of the world's bird species, of which 20 % are endemic to the country, with the highest number concentrated in the Western region. Objective: To analyze composition, diversity and avifaunal distribution along an elevation gradient in Western Mexico. Methods: The research was done in the Sierra de Manantlán Biosphere Reserve. We recorded seen or heard bird species in 28 fixed count points along a 1 000 m elevation gradient. Comparative richness and sampling completeness were determined with interpolation and extrapolation curves. Belts were compared with Non-Parametric Multi-Response Permutation. Correlations and indirect ordinations were used to analyze changes in richness and abundance. Results: We recorded 129 species (estimate: 96 % completeness): 19 endemics to Mexico, 13 in some risk category, and 21 considered indicators. Elevation determined the distribution and abundance of species, and the lower elevational bands, had the highest richness and abundance values. Conclusion: The highest species richness and abundance were recorded at lower elevations, with a significant change in composition and type of indicator species by belt. The numbers of endemic and at-risk species remained constant with elevation.

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La supervivencia de un alto número de especies de aves que se encuentran en la sabana de Bogotá, algunas de ellas endémicas, dependen, en gran medida, de las estrategias incorporadas en las actividades económicas desarrolladas, por ejemplo, las del sector floricultor -cultivos intensivos de flores-, que provee parte del alimento de la avifauna. En las últimas décadas, se evidencia un sostenido incremento en la región de las fincas de floricultivos, generando, en algunos casos, conflictos por traslapes territoriales con la avifauna. En tal sentido, el presente artículo procura analizar la expansión del sector floricultor, en tres municipios de la Sabana de Bogotá: Madrid, El Rosal y Facatativá, relacionándolos con las percepciones sociales de los trabajadores de emprendimientos de floricultivos y su rol en la protección ecológica de las diversas especies de aves, tanto endémicas como migratorias, que llegan a esta parte del territorio colombiano. La metodología implementada correspondió a un diseño mixto, sustentado en la aplicación de tres fases principales: la detección del incremento de los cultivos de flores en los municipios en estudio, mediante el análisis multitemporal de imágenes satelitales; la implementación de encuestas sociales a los trabajadores de los emprendimientos relacionadas con la avifauna presente en las fincas y el análisis socioambiental de la situación en el área de estudio. El fin del trabajo es el de evidenciar la responsabilidad de los emprendimientos floricultores en la protección de la avifauna de la Sabana de Bogotá.

The survival of a high number of bird species found in the Bogota Savanna, some of them endemic, depend to a great extent on the strategies incorporated in the economic activities developed, such as, those of the floriculture sector -intensive crops of flowers-, which provides part of the food of the birdlife. In recent decades, there has been a sustained increase in the region of floriculture farms, generating, in some cases, conflicts due to territorial overlaps with birdlife. In this sense, this article attempts to analyze the expansion of the floriculture sector in three municipalities of the Bogota Savanna: Madrid, El Rosal and Facatativá, relating them to the social representations of the workers of floricultural enterprises and their role in the ecological protection of the various species of birds, both endemic and migratory, that arrive in this part of the Colombian territory. The implemented methodology has had a mixed design based on the application of three main phases: the detection of the increase in flower crops in the municipalities under study through the multitemporal analysis of satellite images, the implementation of social surveys to the workers of the enterprises related to the avifauna present on the farms and the socio-environmental analysis of the situation in the municipalities of Madrid, El Rosal and Facatativá in relation to the topic discussed. The purpose of the work is to demonstrate the responsibility of flower companies in the protection of the birdlife of the Sabana de Bogotá

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The brown treesnake (BTS) (Boiga irregularis) invasion on Guåhan (in English, Guam) led to the extirpation of nearly all native forest birds. In recent years, methods have been developed to reduce BTS abundance on a landscape scale. To help assess the prospects for the successful reintroduction of native birds to Guåhan following BTS suppression, we modeled bird population persistence based on their life history characteristics and relative sensitivity to BTS predation. We constructed individual-based models and simulated BTS predation in hypothetical founding populations for each of seven candidate bird species. We represented BTS predation risk in two steps: risk of being encountered and risk of mortality if encountered. We link encounter risk from the bird's perspective to snake contact rates at camera traps with live animal lures, the most direct practical means of estimating BTS predation risk. Our simulations support the well-documented fact that Guåhan's birds cannot persist with an uncontrolled population of BTS but do indicate that bird persistence in Guåhan's forests is possible with suppression short of total eradication. We estimate threshold BTS contact rates would need to be below 0.0002-0.0006 snake contacts per bird per night for these birds to persist on the landscape, which translates to an annual encounter probability of 0.07-0.20. We simulated the effects of snake-proof nest boxes for Sihek (Todiramphus cinnamominus) and Såli (Aplonis opaca), but the benefits were small relative to the overall variation in contact rate thresholds among species. This variation among focal bird species in sustainable predation levels can be used to prioritize species for reintroduction in a BTS-suppressed landscape, but variation among these species is narrow relative to the required reduction from current BTS levels, which may be four orders of magnitude higher (>0.18). Our modeling indicates that the required predation thresholds may need to be lower than have yet been demonstrated with current BTS management. Our predation threshold metric provides an important management tool to help estimate target BTS suppression levels that can be used to determine when bird reintroduction campaigns might begin and serves as a model for other systems to match predator control with reintroduction efforts.

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