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The study of biomarkers in free-living birds can help to indicate the degree of contamination in distinct environments. In addition, these environments can be characterized through the information provided by satellite images. The objectives of the present study were to analyze the types and quantity of cytogenetic biomarkers in Passer domesticus (House sparrow) from three different environments, wild, rural, and urban, and to analyze them in the context of land use and anthropogenic actions. Five thousand erythrocytes per bird were analyzed for the following nuclear alterations (NA): micronuclei (MN), nuclear buds, notched nuclei, binucleated cells, nucleoplasmic bridges, nuclear tails, peripheral nuclei, and anucleated cells. In the study, wild birds exhibited five types of NA, seven types were found in rural birds, and all types were encountered in urban birds. The only NA that exceeded a frequency of 2 NA/1000 erythrocytes were peripheral nuclei in birds from the rural and urban sites, the latter environment characterized by 87% urban soil and air pollution. The highest frequencies of MN, peripheral nuclei, and anucleated erythrocytes were recorded in sparrows from the rural site (p ≤ 0.05). This area had been sprayed with chlorpyrifos 48%, the most widely used organophosphate in the region. Sparrows from the wild site, made up of 100% native forest, had higher frequencies of notched nuclei (p ≤ 0.05). A precedent is set for the use of environmental remote sensing in a complementary manner with cytogenetic biomarker studies in birds for a joint analysis in environmental assessment.

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Espinilho savanna ("seasonal steppe savanna") is a unique vegetation formation of the Pampas biome that is found near the tri-border of Brazil, Uruguay, and Argentina. The Yellow Cardinal (Gubernatrix cristata) is a flagship species of this ecosystem, but it is classified as "critically endangered" in Brazil due to habitat loss and poaching for the illegal trade. Population supplementation through the release of individuals that were captive-bred or apprehended by authorities from the illegal trade has been considered as a conservation strategy for this species; however, the risk of pathogen introduction is a critical concern. We used microscopy and molecular methods to investigate the occurrence of blood parasites in wild passerines (n = 64, including three Yellow Cardinals) at Espinilho State Park, Rio Grande do Sul, Brazil, and in captive Yellow Cardinals (n = 30) at three facilities in Brazil. Haemosporidian parasites were detected in the blood smears of 10.9% of the wild passerines, comprising the morphospecies Haemoproteus erythrogravidus in Rufous-collared Sparrow (Zonotrichia capensis), H. quiscalus in Grayish Baywing (Agelaioides badius), and H. tyranni in Great Kiskadee (Pitangus sulphuratus); these are the southernmost records for these morphospecies and their first record for the Pampas biome. No haemosporidian parasites were detected in the blood smears of the Yellow Cardinals, wild or captive. Microfilariae were detected in the blood smears of 14.1% of the wild passerines, including all wild Yellow Cardinals, and in 43.3% of captive Yellow Cardinals. Trypanosoma sp. was detected in the blood smear of one captive Yellow Cardinal. Nested PCR and gene sequencing of the cyt-b gene of Haemoproteus/Plasmodium was used to test a subset of wild passerines and captive Yellow Cardinals, allowing for the molecular barcoding of H. quiscalus lineage AGEBAD04 and H. tyranni lineage PITSUL01; additionally, DNA identical to that of lineage PITSUL01 was detected in the blood of one captive Yellow Cardinal. This study provides valuable data to support the conservation management of the Yellow Cardinal and other threatened passerines from the Pampas and highlights the need for further studies on the epidemiology and pathology of filarioid worms and trypanosomes in passerines from this biome.

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The majority of the birds in different habitats are stressed due to alteration in multiple climate factors contributing to their loss. The present study has been planned to find the roosts composition of passerine birds in different major and sub-habitats of Punjab, Pakistan. In Faisalabad, of the four species, the higher number of exits was almost comparable, while Passer domesticus and Pastor roseus were more abundant than Tachycinet bicolor and Lanius cristatus. For the three remaining birds, total exits and returns were 180 for P. roseus, 181 for T. bicolor, and 179 for L. cristatus, respectively. Considering the exits in morning hours, a total of 314, 256, 246 and 210, were recorded from Sheikhupura. In Khanewal, of the four species, the highest exits and returns were that of P. domesticus (407; 451), followed by that of the P. roseus (273; 336), T. bicolor (242; 319) and L. cristatus (220; 397). The temperature imposed serious effects on roost exits for the four birds. The varied P-values which were higher (< 0.001***, < 0.001***, 0.002 **, <0.001***) appeared to limit the roost exits for them. Nonetheless, the impact of relative humidity exerted a strong influence on the T. bicolor (0.003**). In roosts return, it was seen that roost returns were even likely in warm temperatures and precipitation did not impose seriously on returns, and even in light rainfall. Nonetheless, relative humidity (RH) strongly impacted the sparrow. The T. bicolor and L. cristatus were adversely affected with the slopes (1.37) and (2.06), indicated with each percentage increase of relative humidity, and slope variations became least.

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Gene flow in birds can be affected by urbanization depending on natural history traits and adaptability to habitat change. Contrasting results can be expected when comparing species with opposite resilience to urbanization. In this study, we assessed genetic diversity and structure for two bird species, the urban avoider white-eared ground-sparrow, Melozone leucotis, and the urban dweller house wren Troglodytes aedon. We used seven microsatellite loci and sampled five locations with differing levels of urbanization in Costa Rica. We found considerably higher genetic structure in white-eared ground-sparrows than in house wrens. Circuit theory analyses proved a higher isolation from urban resistance for the white-eared ground-sparrow than for house wrens. These results support that urbanization is a significant barrier for gene flow in urban avoiders, in contrast to urban dweller species that showed little to no impact. Differences could be attributed to a higher plasticity in habitat and nesting site preferences in the house wren, and significant dispersal limitation for the white-eared ground-sparrow. These results emphasize the need for conservation strategies towards white-eared ground-sparrows and other urban avoider species whose habitat and connectivity have been reduced by the recent urban expansion.

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The majority of the birds in different habitats are stressed due to alteration in multiple climate factors contributing to their loss. The present study has been planned to find the roosts composition of passerine birds in different major and sub-habitats of Punjab, Pakistan. In Faisalabad, of the four species, the higher number of exits was almost comparable, while Passer domesticus and Pastor roseus were more abundant than Tachycinet bicolor and Lanius cristatus. For the three remaining birds, total exits and returns were 180 for P. roseus, 181 for T. bicolor, and 179 for L. cristatus, respectively. Considering the exits in morning hours, a total of 314, 256, 246 and 210, were recorded from Sheikhupura. In Khanewal, of the four species, the highest exits and returns were that of P. domesticus (407; 451), followed by that of the P. roseus (273; 336), T. bicolor (242; 319) and L. cristatus (220; 397). The temperature imposed serious effects on roost exits for the four birds. The varied P-values which were higher (< 0.001***, < 0.001***, 0.002 **, <0.001***) appeared to limit the roost exits for them. Nonetheless, the impact of relative humidity exerted a strong influence on the T. bicolor (0.003**). In roosts return, it was seen that roost returns were even likely in warm temperatures and precipitation did not impose seriously on returns, and even in light rainfall. Nonetheless, relative humidity (RH) strongly impacted the sparrow. The T. bicolor and L. cristatus were adversely affected with the slopes (1.37) and (2.06), indicated with each percentage increase of relative humidity, and slope variations became least.

A maioria das aves em diferentes habitats está estressada devido à alteração em vários fatores climáticos que contribuem para sua perda. O presente estudo foi planejado para encontrar a composição dos poleiros de aves passeriformes em diferentes, grandes e sub-habitats de Punjab, no Paquistão. Em Faisalabad, das quatro espécies, tem-se que o maior número de saídas foi quase comparável, enquanto que as espécies Passer domesticus e Pastor roseus foram mais abundantes que Tachycinet bicolor e Lanius cristatus. Para as três aves restantes, o total de saídas e retornos foi de 180 para P. roseus, 181 para T. bicolor e 179 para L. cristatus, respectivamente. Considerando as saídas nas horas da manhã, um total de 314, 256, 246 e 210 foi registrado de Sheikhupura. Em Khanewal, das quatro espécies, as maiores saídas e retornos foram de P. domesticus (407; 451), seguidas de P. roseus (273; 336), T. bicolor (242; 319) e L. cristatus (220; 397). A temperatura impôs sérios efeitos nas saídas dos poleiros para as quatro aves. Os maiores valores de p variados (< 0,001***, < 0,001***, 0,002 **, <0,001***) pareceram limitar as saídas de poleiro para os pássaros. No entanto, o impacto da Umidade Relativa (UR) exerceu forte influência sobre o T. bicolor (0,003**). Com relação ao retorno dos poleiros, verificou-se que esses retornos eram até prováveis ​​em temperaturas quentes, visto que a precipitação não foi um fator extremamente determinante para os retornos, mesmo em chuvas fracas. No entanto, a UR impactou fortemente o pardal. O T. bicolor e L. cristatus foram prejudicados com as declividades (1,37) e (2,06), que foram indicadas a cada percentual de aumento de UR, ao passo que as variações de declividade tornaram-se menores.

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Chlorospingus flavopectus, a widely distributed member of the New World sparrows and finches (Passerellidae), is among the most variable and complex Neotropical bird species. With up to 28 subspecies that inhabit montane forest from Mexico south to Argentina, it presents a recurring leapfrog pattern, with many genetically differentiated lineages, but even more morphologically distinguishable taxa. Chlorospingus flavopectus phaeocephalus is distributed along the eastern Andean slope (from southern Colombia to northern Peru) and in localized patches along the central and southwestern slopes of the Ecuadorian Andes, in the forest remnants of Chimborazo, El Oro, and adjacent Loja provinces. This allopatric distribution was based on plumage similarities, but no genetic or vocal analysis has tested if these populations share a common ancestry. Here, we compared data for populations of C. f. phaeocephalus, C. semifuscus semifuscus from northwest Ecuador, and C. s. livingstoni from west Colombia, and analyzed them in the context of other Chlorospingus. Our phylogenetic analyses revealed that the putative west Ecuadorian populations of C. f. phaeocephalus are nested within C. semifuscus. They also present diagnostic characters when compared to other populations of C. semifuscus and C. f. phaeocephalus. Based on these results, we recognize the population from El Oro and adjacent Loja Provinces as a new subspecies of C. semifuscus, and the population from Chimborazo Province as a morphological variation of C. s. semifuscus.

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Invasive species impact native wildlife in several ways, as they compete for resources and may transmit their specific pathogens. However, the potential consequences of co-introduced parasites are not fully understood. While the house sparrow (Passer domesticus) was introduced in Chile about a century ago, no data are available regarding its parasites. Thus, the aim of the present study was to determine the parasitic fauna of this avian invader and to determine whether there are co-introduced/co-invasive parasites shared with native birds. One hundred and eight birds were collected from three different localities in the Ñuble region of Chile, and a complete parasitic necropsy was performed in the laboratory. Twenty-three (21.3%) were parasitized by six arthropod species and four (3.7%) were parasitized by two helminth species. Four out of eight taxa are reported for the first time in Chile; among them, three arthropod parasites and the tapeworm, Anonchotaenia globate, are considered as co-introduced parasites. Only A. globata is a potential co-invasive parasite given its low degree specificity in terms of its definitive hosts. Future research should examine whether additional co-introduced/co-invasive parasites have been brought by the house sparrow, and what their potential consequences might be on the health of native birds in Chile.

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Noise affects the recognition of acoustic signals by masking information. To compensate for increased noise, individuals often increase the minimum frequency of their vocalization to reduce noise interference. Our goal was to analyze the effect of noise on the characteristics of different bird vocalizations, through a comparative study of vocalizations on the same bird species. We analyzed the effects of noise variation on the fine spectrotemporal characteristics of calls, songs, and duets of White-eared Ground-sparrows (Melozone leucotis) across three populations over a three-year period. We recorded vocalizations and noise levels simultaneously from 41 territories between 2012 and 2014. We measured the duration, minimum, maximum, and maximum amplitude frequency, and counted the number of songs elements for each vocalization recorded. As we predicted, noise influences the minimum frequency of song, but did not have an effect on the fine spectrotemporal characteristics for calls and duets. We did, however, find that low and high frequency of calls and duets increased with noise-population-year interaction. Our results suggest that differences in noise values at each population were inadequate to observe changes in vocalization characteristics. In conclusion, evaluating responses to different noise levels on different vocalization types for the same species expands our understanding of the flexibility of birds to adjust vocalizations in response to anthropogenic noise.

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Abstract Invasive species impact native wildlife in several ways, as they compete for resources and may transmit their specific pathogens. However, the potential consequences of co-introduced parasites are not fully understood. While the house sparrow (Passer domesticus) was introduced in Chile about a century ago, no data are available regarding its parasites. Thus, the aim of the present study was to determine the parasitic fauna of this avian invader and to determine whether there are co-introduced/co-invasive parasites shared with native birds. One hundred and eight birds were collected from three different localities in the Ñuble region of Chile, and a complete parasitic necropsy was performed in the laboratory. Twenty-three (21.3%) were parasitized by six arthropod species and four (3.7%) were parasitized by two helminth species. Four out of eight taxa are reported for the first time in Chile; among them, three arthropod parasites and the tapeworm, Anonchotaenia globate, are considered as co-introduced parasites. Only A. globata is a potential co-invasive parasite given its low degree specificity in terms of its definitive hosts. Future research should examine whether additional co-introduced/co-invasive parasites have been brought by the house sparrow, and what their potential consequences might be on the health of native birds in Chile.

Resumo As espécies invasoras de vertebrados competem com espécies nativas no uso de recursos e transmitem patógenos. Contudo as consequências da co-introdução de parasitos permanecem pouco estudadas. O pardal (Passer domesticus) foi introduzido há um século no Chile, porém não existem dados sobre seus parasitos. O objetivo do estudo foi investigar a fauna parasitária e avaliar se existem espécies co-introduzidas/co-invasivas compartilhadas com as espécies de aves nativas do Chile. Um total de 108 aves foram coletadas em diferentes localidades da região de Ñuble. Seis espécies de artrópodes parasitos foram coletadas de 23 (21,3%) aves. Quatro aves (3,7%) estavam parasitadas por duas espécies de helmintos. Quatro de um total de oito espécies de parasitos correspondem aos primeiros relatos para o Chile. Três artrópodes parasitos e o helminto Anonchotaenia globata são considerados parasitos co-introduzidos no país. Apenas A. globata possui potencial para ser considerada uma espécie co-invasiva, pois pode parasitar Passeriformes em geral. Pesquisas futuras devem investigar se os demais parasitos identificados neste estudo correspondem a espécies co-introduzidas ou co-invasoras e avaliar as possíveis consequências na saúde das aves nativas do país.

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