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1.
Rev. biol. trop ; 71(1)dic. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1449517

RESUMO

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.

2.
Biology (Basel) ; 12(5)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37237508

RESUMO

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.

3.
Ecol Evol ; 13(3): e9880, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36911311

RESUMO

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.

4.
Pol J Vet Sci ; 26(1): 47-55, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36961268

RESUMO

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.


Assuntos
Infecções por Escherichia coli , Salmonella enterica , Animais , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/microbiologia , beta-Lactamases/genética , Columbidae , Incidência , Paquistão/epidemiologia , Antibacterianos/farmacologia , Salmonella enterica/genética
5.
PeerJ ; 11: e14801, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36815977

RESUMO

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.


Assuntos
Biodiversidade , Ecossistema , Humanos , Animais , Aves , China , Chá
6.
Biodivers Data J ; 11: e95670, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327332

RESUMO

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.

7.
Braz. j. biol ; 83: e248842, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339343

RESUMO

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.


Assuntos
Animais , Praguicidas/toxicidade , Paquistão , Acetilcolinesterase , Aves , Inibidores da Colinesterase/toxicidade , Ecossistema , Produtos Agrícolas
8.
Braz. j. biol ; 83: 1-8, 2023. map, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468925

RESUMO

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.


Assuntos
Animais , Acetilcolinesterase/deficiência , Doenças das Aves/diagnóstico , Doenças das Aves/induzido quimicamente , Praguicidas/envenenamento
9.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469141

RESUMO

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.

10.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1537070

RESUMO

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

11.
Rev. biol. trop ; 70(1)dic. 2022.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1387703

RESUMO

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.


Assuntos
Animais , Aves/classificação , México
12.
Ecol Appl ; 32(8): e2716, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36178004

RESUMO

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.


Assuntos
Aves , Comportamento Predatório , Animais , Guam
13.
CienciaUAT ; 16(2): 6-25, ene.-jun. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1374897

RESUMO

Resumen Los sistemas agroforestales pueden representar importantes nichos ecológicos que coadyuven a la conservación de la diversidad avifaunística. El objetivo de este trabajo fue estimar y comparar la diversidad y uso de hábitat de aves insectívoras en sistemas agroforestales enclavados en un bosque mesófilo de montaña. Se efectuó el monitoreo de aves de agosto de 2018 a enero de 2019 en tres hábitats: café tradicional (CT), potrero (PT) y bosque mesófilo de montaña (BMM). Se determinaron índices de abundancia relativa (IAR), riqueza (Jacknife1), similitud (Jaccard) y diversidad (Shannon-Wiener). El IAR presentó valores bajos para los tres hábitats. El método Jacknife1 denotó una riqueza promedio considerable para las tres áreas (CT: 33.02, PT: 24.20, BMM: 9.98, CT-PT-BMM: 52.22). La técnica de Jaccard registró poca similitud en la riqueza, reafirmando el efecto del hábitat, composición y estructura florística como factores determinantes, al mismo tiempo que estableció promedios de diversidad alta obtenidos mediante el método de Shannon-Wiener (H´= 3.3; 3.1; 2.27; 3.78, respectivamente), revelando una diversidad relativamente estable en los tres hábitats. Por su parte, Kruskal-Wallis advirtió diferencias en la diversidad, pero no para la riqueza y la abundancia. Se evidenció la conformación declústeresy agrupaciones que encontraron mayor similitud entre la riqueza y la abundancia de especies por cada monitoreo aplicado. El análisis de componentes principales indicó mayor correlación del hábitat y la vegetación utilizados para la alimentación en el estrato herbáceo y arbóreo, en alturas que van de 5 m a 10 m, utilizando el estrato aéreo para vuelo. Los sistemas agroforestales estudiados constituyeron un nicho de oportunidad en donde la avifauna halló alimento, áreas de nidación y reproducción. Se recomienda la implementación de buenas prácticas de manejo agroforestal que coadyuven a la conservación de especies.


Abstract Agroforestry systems can represent important ecological niches that contribute to the conservation of bird diversity. The objective of this work was to estimate and compare the diversity and habitat use of insectivorous birds in agroforestry systems located in a montane cloud forest. Bird monitoring was carried out from August 2018 to January 2019 in three habitats: traditional coffee plantation (CT), paddock (PT) and montane cloud forest (BMM). Relative abundance (IAR), richness (Jacknife1), similarity (Jaccard) and diversity (Shannon-Wiener) indices were determined. The IAR presented low values for the three habitats. The Jacknife1 method denoted considerable average richness for the three areas (CT: 33.02, PT: 24.20, BMM: 9.98, CT-PT-BMM: 52.22). The Jaccard technique recorded little similarity in richness, reaffirming the effect of habitat, composition and floristic structure as determining factors, which at the same time established high diversity averages, obtained by the Shannon-Wiener method (H´= 3.3; 3.1 ; 2.27; 3.78, respectively), revealing a relatively stable diversity in the three habitats. For his part, Kruskal-Wallis noticed differences in diversity, but not for richness and abundance. The formation of clusters and groups that found greater similarity between the richness and abundance of species for each applied monitoring was evidenced. Principal component analysis indicated a higher correlation of habitat and vegetation used for feeding in the herbaceous and arboreal stratum, at heights ranging from 5 m to 10 m, using the aerial stratum for flight. The agroforestry systems studied constituted a niche of opportunity where the avifauna found food, nesting and reproduction areas. The implementation of good agroforestry management practices that contribute to the conservation of species is recommended.

14.
J Hum Evol ; 167: 103185, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35489251

RESUMO

Several large-bodied hominin and nonhuman primates have coexisted in the Cradle of Humankind in South Africa during the Early Pleistocene. Previous paleoenvironmental studies regarding the Plio-Pleistocene of South Africa have focused heavily on mammal assemblages. Here, we conducted a comprehensive taxonomic analysis of the fossil bird remains from Cooper's D, the most fossiliferous locality of the hominin-bearing Cooper's Cave complex in South Africa. Our taxonomic evaluation of 505 remains reveals the presence of 23 bird taxa, two of which are extinct and already reported from the nearby fossil locality of Kromdraai. The taxonomically diverse bird assemblage is dominated by Francolinus sp. and other species associated with open grassland habitats, followed by rock-dwelling species, including Tyto cf. alba and the extinct Corvus bragai, and by woodland species such as Agapornis sp., Accipiter melanoleucos, and the extinct Glaucidium ireneae. The occurrence of these taxa and their respective proportions in the assemblage, in terms of both numbers of bones and individuals, point to the presence of extensive open grassland and/or savannah with rocky outcrops and woodland. These findings corroborate previous analyses of mammals from Cooper's D, with the exception of aquatic species, which are rare in the bird assemblage. Comparison with older deposits from Kromdraai confirms the definitive establishment of open habitats in the Cradle of Humankind during the Early Pleistocene following a transition from woodier habitats during the Late Pliocene. This study constitutes a further step in investigating the fossil bird diversity in the Cradle of Humankind during the Plio-Pleistocene. Our results add to the larger body of work using avian fossils for paleoenvironmental reconstructions in Africa and support the utility of birds as paleoenvironmental proxies. Similar future studies will refine our understanding of the paleoenvironments and landscape transformation during the Plio-Pleistocene, a critical timeframe for hominin evolution in southern Africa.


Assuntos
Fósseis , Hominidae , Animais , Aves , Mamíferos , África do Sul
15.
J Hazard Mater ; 434: 128814, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427965

RESUMO

In recent years, there has been a growing number of studies on the impact of microplastics (MPs) on biota. However, its effects on birds' health are poorly understood. Thus, we aimed to evaluate the possible effects of ingestion of naturally-aged MPs by Coturnix Coturnix japonica (11 and 22 MP particles/day/bird, once a day, for 9 days), from different toxicity biomarkers. At the end of the experiment, it was found that the ingested MPs in birds showed a significant reduction in body biomass. Also, an increase in malondialdehyde production in the liver, brain, intestine, and gizzard of the birds, as well as a suppressive effect on hepatic nitric oxide production and superoxide dismutase activity in the liver and intestine were observed. Cerebral catalase activity was reduced in birds exposed to MPs and the cholinesterasic effect (marked by increased acetylcholinesterase activity) was observed in the muscle and brain of these animals. Despite these differences, through the main component analysis, hierarchical clustering analysis, and integrated biomarker response assessment, we observed similar toxicological effects in birds exposed to different amounts of MPs. In addition, the size of MPs was reduced, and their shape was altered as they transited through the gastrointestinal system, which probably explains their accumulation in the liver of birds. An expressive number of MPs are released through the feces of the birds throughout the experiment. As far as we know, this is the first report that associates MPs ingestion by small-sized terrestrial birds with biochemical alterations viz., predictive of oxidative stress, redox imbalance, and cholinesterasic effect, in addition to shedding light on the potential role of these birds as vectors for dispersal of MPs in natural environments.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Acetilcolinesterase , Animais , Coturnix , Ingestão de Alimentos , Poluentes Ambientais/análise , Microplásticos/toxicidade , Plásticos/toxicidade , Poliestirenos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
16.
Rev. peru. biol. (Impr.) ; 29(1): e20667, ene.-mar. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1377188

RESUMO

Resumen La cordillera del Kutukú está ubicada al sureste de Ecuador y se encuentra parcialmente aislada de la cordillera de los Andes. Realizamos cinco expediciones a este macizo, donde obtuvimos de manera directa información referente a la riqueza de aves. Además, con el fin de generar un listado más completo, realizamos una recopilación de registros publicados y revisamos colecciones de museos ecuatorianos. En total registramos 501 especies de aves, en un rango entre 500 - 2300 m de altitud. Encontramos trece especies con nuevas ampliaciones de distribución altitudinal y/o latitudinal. Veintiséis especies de aves (5.2%) están en alguna categoría de amenaza a su conservación, a nivel mundial y nacional. Las escasas vías de acceso, sumadas a las políticas de ingreso al territorio, por parte de la etnia Shuar, han favorecido la preservación de los bosques, especialmente aquellos por encima de los 1800 m. Es así que, el conocimiento biológico de esta área queda aún por descubrir. Esta zona remota protege una importante diversidad, así como poblaciones de aves amenazadas, recursos hídricos, además del territorio y cultura de las comunidades que la habitan. Desafortunadamente la totalidad de la cordillera se encuentra concesionada para exploraciones de proyectos mineros. Por tanto, se requiere la atención de las autoridades regionales y nacionales para aunar esfuerzos que aseguren su conservación y exploración biológica.


Abstract The cordillera del Kutukú is located in the southeastern Ecuador and is partially isolated from the Andes mountain range. We conducted five field expeditions to the region, where we directly obtained information regarding the richness of birds. In addition, we compile bird richness data from published records and Ecuadorian museum's collections in order to provide an updated list. A total of 501 bird species were registered, in an elevation range from 500 to 2.300 m a.s.l. We found 13 species with new latitudinal and/or longitudinal distribution extensions. Twenty-six species (5.2%) are in an elevated risk category nationally or globally. The region's limited roads, added to the Shuar ethnic group policies for entering to their territory has aided in the conservation of forests, especially those over 1800 m a.s.l. Thus, the biological knowledge of this area remains to be discovered. This remote area protects an important diversity, as well as threatened bird populations, water resources, territory and culture of the indigenous groups that inhabit it. However, unfortunately the entire mountain range is under concession for exploration of mining projects. Therefore, the attention of regional and national authorities is required to join efforts to ensure their conservation and biological exploration.

17.
J Environ Manage ; 303: 114131, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838379

RESUMO

The management of agroecosystems affects biodiversity at all levels from genetic to food-web complexity. Low-input farming systems support higher levels of genetic, species and habitat diversity than high-input, industrial ones. In Greece, as in other Mediterranean countries, the role of traditional farming practices has been underlined in studies concerning conservation in agricultural landscapes. With this study, we aim to provide evidence for the potential of semi-extensive farming for biodiversity conservation at landscape-scale, focusing on Lemnos, a medium-sized island in the North Aegean. Evidence was gathered by species- and community-level local-scale surveys on various trophic levels (vascular plants, arthropods, birds). The surveys took place in 2018 and 2019 in 25 sampling areas comprising 106 plots of 100 m2 (vascular plants, arthropods) and 57 points where bird species were recorded. The plots were classified into three landscape types: mosaic agriculture, mixed rangelands and uniform rangelands. The relevés of Lemnos farmlands were assigned to plant communities of 18 phytosociological alliances, grouped into 12 classes. The most abundant arthropods were Coleoptera, Chilopoda, and Hymenoptera, followed by Opiliones and Isopoda, while 133 different bird species were recorded in total, including the recording for the first time on the island of five species. Farming on Lemnos is rather extensive compared to most agricultural landscapes of Europe. Our approach has demonstrated that, given the geographic characteristics of the area, the measured data reveal very high biodiversity. Our explorative findings suggest that moderate seasonal grazing, the mixed habitat mosaic with ecotones, fallow and stubble fields at the landscape scale, and the small size of fields, the kinds of crop, and farm-scale crop diversification, like mixed cultivation and crop rotation, are key practices supporting this diversity. These explorative findings are considered as a first step providing the baseline for future assessments. A wider effort, for systematic evaluation of the impacts of farming practices to biodiversity, is required, as part of a subsidized agri-environmental scheme and/or through a market-oriented product certification system for the area.


Assuntos
Agricultura , Biodiversidade , Animais , Ecossistema , Fazendas , Grécia
18.
Environ Sci Pollut Res Int ; 29(10): 14279-14287, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34606051

RESUMO

Free-living birds play an important role as bioindicators in natural environments. In this study, we used the micronucleus test and nuclear erythrocyte abnormalities to investigate the difference in the genotoxic damage frequency between animals in agricultural areas (soybean planting) in relation to the conserved area. It was also discussed the bird's eating habits, which are important for ecotoxicological analysis. The results point to a difference between the insectivorous, granivorous, and omnivorous guilds. The omnivore Gnorimopsar chopi was the species that most exhibited micronucleus frequency in the protected area. In the agricultural area, the animals did not differ in the genotoxic damage frequency. In the comparison between common species in both environments, G. chopi from the agricultural area showed a micronuclei frequency almost three times higher in relation to specimens collected in the conserved area. Based on these results, this study adds to the efforts of using the micronucleus test as a simple and accessible tool for biomonitoring the wild fauna. It can be concluded that the passerine, G. chopi, due to its higher genotoxic damage frequency may be a strong candidate to indicate environmental health.


Assuntos
Animais Selvagens , Aves/genética , Dano ao DNA , Testes para Micronúcleos , Agricultura , Animais , Animais Selvagens/genética , Brasil , Ecotoxicologia , Monitoramento Ambiental , Passeriformes/genética
19.
Biodivers Data J ; 9: e72075, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34776734

RESUMO

BACKGROUND: Birds are the most numerous and widespread group of higher vertebrates. Due to the peculiarities of their biology, birds play an important role in nature and in human life.Ornithological studies described in this publication were conducted in seven regions of the Middle Volga Region (Chuvashia, Mordovia, Tatarstan, Samara, Nizhny Novgorod, Ulyanovsk and Penza Regions) from 1978 to 2021. Visual and acoustic methods were used to study the species composition during field studies. In total, 5065 birdoccurrences belonging to 157 species, 48 families and 19 orders were registered. All occurrences have a geographical reference. The large volume of data collected, the wide geographical coverage and the long-term nature of the observations determined the value of their inclusion in the GBIF and the need for publication in the Biodiversity Data Journal. NEW INFORMATION: We are publishing our original data on the coordinates of bird occurrences in the Middle Volga Region for the first time. Most of the original information about bird occurrences was contained in field diaries and was not available to a wide range of researchers. All 5065 occurrences are new to GBIF.

20.
Curr Zool ; 67(4): 431-440, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34616940

RESUMO

Strong correlations between species diversity and climate have been widely observed, but the mechanism underlying this relationship is unclear. Here, we explored the causes of the richness-climate relationships among passerine birds in China by integrating tropical conservatism and diversification rate hypotheses using path models. We found that assemblages with higher species richness southwest of the Salween-Mekong-Pearl River Divide are phylogenetically overdispersed and have shorter mean root distances (MRDs), while species-rich regions northeast of this divide (e.g., north Hengduan Mountains-south Qinling Mountains) are phylogenetically clustered and have longer MRDs. The results of the path analyses showed that the direct effect of climatic factors on species richness was stronger than their indirect effects on species richness via phylogenetic relatedness, indicating that neither tropical conservatism nor diversification rate hypotheses can well explain the richness-climate relationship among passerines in China. However, when path analyses were conducted within subregions separately, we found that the tropical conservatism hypothesis was well supported in the southwestern Salween-Mekong-Pearl River Divide, while the diversification rate hypothesis could explain the richness-climate relationship well in the northeastern divide. We conclude that the diversity patterns of passerines in different subregions of the Eastern Himalayas-Mountains of Southwest China may be shaped by different evolutionary processes related to geological and climatic histories, which explains why the tropical conservatism or diversification rate hypothesis alone cannot fully explain the richness-climate relationships.

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