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Urban trees enhance biodiversity, provide ecosystem services, and improve quality of life in cities. Despite their benefits, trees are not distributed equitably, and many cities exhibit a "luxury effect". Given the importance of public green space for providing access to urban tree benefits, we investigated the relationship between socioeconomic level and tree diversity and structure in 60 green areas in Santiago de Chile. Species richness and total tree abundance did not significantly vary among socioeconomic levels; however, a differential effect was found according to species origin. Introduced tree species exhibited similar abundance and species richness across socioeconomic levels, but native tree species were more abundant and richer in higher socioeconomic level areas compared to lower ones. Tree cover was higher in the high and medium socioeconomic level areas than in the low socioeconomic level area. A higher average DBH was found in the medium socioeconomic level area, which may be explained by older neighborhoods and a legacy of the luxury effect. Our findings reveal that socioeconomic groups are associated with differences in tree cover, width, and the number of native species in public green areas. Consequently, urban residents have different provisions of ecosystem services and opportunities to interact with natural heritage. Increasing the amount of tree cover and native species available to vulnerable groups will reduce disparities.

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The World Health Organization categorizes air pollution as the presence of one or more contaminants in the atmosphere such as smoke, dust, and particulate matter like microplastics, which are considered a priority pollutant. However, only a few studies have been developed on atmospheric pollution, and knowledge about MPs in the atmosphere is still limited. Spider webs have been tested and used as a passive sampling approach to study anthropogenic pollution. Despite this, studies on microplastic contamination using spiderwebs as samplers are scarce. Thus, this study uses spider webs as passive indicators to investigate air quality regarding microplastic contamination in an urbanized area. Therefore, 30 sampling points were selected, and webs of Nephilingis cruentata were collected. The spider webs were dipped in KOH 10 %. After digestion, the solution was washed and sieved through a 90 µm geological sieve. The remaining material was transferred to a Petri dish with filter paper, quantified, and identified by type and color. The chemical composition of the polymers was determined using Raman spectroscopy. 3138 microplastics were identified (2973 filaments and 165 fragments). The most frequent colors were blue and black. Raman spectroscopy revealed five types of polymers: Isotactic Polypropylene, Polyethylene Terephthalate, Polyurethane, Polyamide, and Direct Polyethylene.

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Climate change will substantially increase extreme rainfall events, especially in the Tropics, enhancing flood risks. Such imminent risks require climate adaptation strategies to endure extreme rainfall and increase drainage systems. Here, we evaluate the potential of nature-based solutions by using an ecosystem service modeling approach, evaluating the impact of extreme rainfall events on flood risks in a large urban area and with a real-world land recovery plan. We evaluate the cost-effectiveness of four different land recovery scenarios and associated co-benefits, based on a gradient increase in area recovered and cost of implementation. Although the scenarios reveal increasing flood risk reduction and co-benefits along with greater proportion of land recovery, the most cost-effective scenario was the one with an intermediate land recovery where 30% of the study area would be reforested. We emphasize the striking benefits of nature-based solutions for flood risk reduction in cities, considering landscape scale and stakeholders' needs.

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The progressive growth of urban environments has increasingly forced populations of nonhuman primates to coexist with humans in many cities, which has resulted in problems such as behavioral alterations, conflicts with humans, and threats to the health of the monkeys, due to their consumption of anthropogenic foodstuffs. These anthropogenic foods, which are rich in calories, are the principal driver of the proximity between humans and primates, even though the acquisition of these foods tends to be risky for the monkeys and involve a variety of challenges derived from specific features of the urban environment. The present study evaluated the success/risk relationship of foraging for anthropogenic food by tufted capuchins (Sapajus libidinosus) in Brasília National Park. The data were analyzed using a binary logistic regression, with the backward-stepwise Wald method, to investigate the factors related to the foraging success of the capuchins, considering variables such as their sex and age, the type of approach and its context, and interactions with humans. The capuchins were influenced by the anthropogenic context, which affected their foraging strategies and diet. Interactions with humans reduced the success of foraging for anthropogenic foods. Conflicts between humans and the capuchins were common, especially in the context of access to food. The capuchins thus preferred to access feeding resources directly, probably due to the reduced human interference, which resulted in greater foraging success for unattended food brought by park visitors and the raiding of trash cans. Based on the observed behavior patterns, a number of measures can be proposed to mitigate these conflicts. These recommendations include not bringing food into areas frequented by the capuchins, not reacting to approaching animals, and removing all trash generated during a visit. A cleaning team dedicated to the maintenance of the visitation area free of anthropogenic waste is also be recommended.

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Many animal species depend on sound to communicate with conspecifics. However, human-generated (anthropogenic) noise may mask acoustic signals and so disrupt behavior. Animals may use various strategies to circumvent this, including shifts in the timing of vocal activity and changes to the acoustic parameters of their calls. We tested whether pied tamarins (Saguinus bicolor) adjust their vocal behavior in response to city noise. We predicted that both the probability of occurrence and the number of long calls would increase in response to anthropogenic noise and that pied tamarins would temporally shift their vocal activity to avoid noisier periods. At a finer scale, we anticipated that the temporal parameters of tamarin calls (e.g., call duration and syllable repetition rate) would increase with noise amplitude. We collected information on the acoustic environment and the emission of long calls in nine wild pied tamarin groups in Manaus, Brazil. We found that the probability of long-call occurrence increased with higher levels of anthropogenic noise, though the number of long calls did not. The number of long calls was related to the time of day and the distance from home range borders-a proxy for the distance to neighboring groups. Neither long-call occurrence nor call rate was related to noise levels at different times of day. We found that pied tamarins decreased their syllable repetition rate in response to anthropogenic noise. Long calls are important for group cohesion and intergroup communication. Thus, it is possible that the tamarins emit one long call with lower syllable repetition, which might facilitate signal reception. The occurrence and quantity of pied tamarin' long calls, as well as their acoustic proprieties, seem to be governed by anthropogenic noise, time of the day, and social mechanisms such as proximity to neighboring groups.

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Urbanization is one of the more important phenomena affecting biodiversity in the Anthropocene. Some organisms can cope with urban challenges, and changes in birds' acoustic communication have been widely studied. Although changes in the timing of the daily organization of acoustic communication have been previously reported, there is a significant gap regarding possible variations in song structure between dawn and dusk choruses. Considering that urbanization imposes different soundscapes for dawn and dusk choruses, we postulate two hypotheses: (i) there are variations in song parameters between dawn and dusk choruses, and (ii) such parameters within the city will vary in response to urban noise. We studied urban and extra-urban populations of Chiguanco Thrush in La Paz, Bolivia, measuring in dawn and dusk choruses: song length; song sound pressure level; minimum, maximum, range and dominant frequency; and the number of songs per individual. The results support our two hypotheses: there were more songs, and songs were louder and had larger band widths at dawn than at dusk in urban and extra-urban populations. Urban Chiguanco Thrushes sing less, the frequency of the entire song rises, and the amplitude increases as compared with extra-urban Chiguanco Thrushes. Understanding variations between dawn and dusk choruses could allow for a better interpretation of how some bird species cope with urban challenges.

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The mutualistic relationship between plants and arbuscular mycorrhizal (AM) fungi is essential for optimal plant nutrition, enabling plants to better withstand biotic and abiotic stressors and enhancing survival, reproduction, and colonization of new environments. Activities, such as soil enrichment or compaction, may decrease the benefits of AM fungi for plants, potentially reducing interactions in urban environments. Here, we examine this prediction by studying how urbanization alters AM interactions with the invasive herb Ruellia nudiflora (Acanthaceae). We collected soil and plants from deep urban sites (DUS; e.g., sidewalks), open urban sites (OUS; parks), and rural sites (RS) to analyse soil nutrient content, plant morphology, AM colonization rates, spore density, richness, and diversity. Contrary to predicted, DUS had the lowest soil nutrient concentration, except for phosphorus, reducing AM colonization. This supports the prediction of reduced AM interactions in urban environments. We also found that potassium affects the AM association. Urban plants had smaller and more compact root systems compared to their rural counterparts, but there were no discernible differences in AM fungi communities between urban and rural environments. Phosphorus enrichment in sidewalks is the main driver of reductionof R. nudiflora-AM fungi interactions in Mérida. More studies are needed to gain a better understanding of how AM fungi contribute to plant colonization in urban environments.

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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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Urbanization stands out as a significant anthropogenic factor, exerting selective pressures on ecosystems and biotic components. A notable outcome of urbanization is thermal heterogeneity where the emergence of Urban Heat Islands is characterized by elevated air and surface temperatures compared to adjacent rural areas. Investigating the influence of thermal heterogeneity on urban animals could offer insights into how temperature variations can lead to phenotypic shifts. Urban pigeons (Columba livia) serve as an excellent model for studying urban thermal effects, given the melanism variations, which are associated with the pleiotropy of the melanocortin system. To examine the development of physiological plasticity in response to urban thermal variations, we conducted a study on pigeons in Santiago, Chile, during the rainy season. We assessed the influence of habitat on physiological traits related to metabolism and antioxidant capacities, which are theoretically affected by feather coloration. Our findings reveal that variations in melanism significantly impact pigeon physiology, affecting both antioxidant capacities and the mitochondrial activity of red blood cells. It was found that higher urban temperatures, from both the current sampling month and the prior sampling month (from CRU TS dataset), were negatively and strongly associated with lower antioxidant and metabolic activities. This suggests that elevated urban temperatures likely benefit the energetic budgets of pigeon populations and mitigate the negative effects of oxidative metabolism, with differential effects depending on feather colorations.

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Zoonotic Cryptosporidium meleagridis was identified in invasive monk parakeets (Myiopsitta monachus) from Santiago metropolis in Chile. Oocysts were isolated from nestlings' faeces, and a fragment of 18S ribosomal RNA gene was amplified and sequenced. This finding emphasizes the importance of permanent pathogen monitoring in synanthropic species with wide global distribution.

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Free-roaming dogs are an important concern for public health, livestock production and the environment. Human behaviors-such as allowing pets to roam, abandoning dogs, or feeding stray animals-could influence free-roaming dog abundance and the frequency of occurrence of dog-caused problems. Here we aim to determine patterns of free-roaming dog abundance in urban and rural areas, to reveal spatial variation in human behaviors underlying the free-roaming dog problem, and to test for associations between free-roaming dog abundance and related problems. We conducted our study in Chile, where dogs are a major environmental issue. In Chile, as in many other Global South countries, many people leave their dogs to roam, partly due to norms and to lax enforcement of dog control laws. To address our objectives, we counted dogs in 213 transects in urban and rural areas to model dog abundance using N-mixture models. Then we conducted interviews in 553 properties around the transects to determine people's dog management, their behavior towards free-roaming dogs and the prevalence of dog-caused problems. Dog abundance was higher in transects where a higher number of owned dogs was allowed to roam, as well as in lower-income neighborhoods (based on property tax valuation). Meanwhile, rural citizens were more likely to let their dogs' roam. Dog abandonment was reported more frequently in lower-income urban neighborhoods and rural areas. Not surprisingly, we found that several problems-such as dog bites-were more frequent where we detected more free-roaming dogs. Our results highlight that the owned dog population is a central component of the free-roaming dog problem, and that human behavior is the key driver underlying the problem. Dog management programs should promote responsible dog-ownership, with a strong message focused on keeping dogs inside properties and preventing abandonment.

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Although drosophilids have been extensively studied in laboratories worldwide, their ecology is still relatively poorly understood. This is unfortunate because some species are currently expanding their geographic distribution and infesting fruit crops. Here, we investigated the relationship between drosophilids and potential plant hosts in a commercial fruit and vegetable distribution center in the Neotropical region. We collected discarded fruits and vegetables from this commercial center during two time periods (2007-2008 and 2017-2018). Resources were weighted and individually monitored in the laboratory. The drosophilids that emerged were identified, and the relationship between them and their resources was explored. From the 99,478 kg of potential hosts collected, we identified 48 plant taxa, from which 48,894 drosophilids of 16 species emerged. On both collecting occasions, drosophilid assemblages were strongly dominated by basically the same exotic species, which explore a broader range of resources, especially those of exotic origin, when compared to neotropical drosophilids. These results are concerning because the studied site, Along with other urban markets around the world, might be acting as sources of generalist widespread species that disperse to surrounding natural vegetation and contribute to biotic homogenization.

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Earth observation environmental features measured through remote sensing and models of vector mosquitoes species Aedes aegypti and Ae. albopictus provide an advancement with regards to dengue risk in urban environments of subtropical areas of Argentina. The authors aim to estimate the effect of landscape coverage and spectral indices (Normalized Difference Vegetation Index [NDVI], Normalized Difference Water Index [NDWI] and Normalized Difference Built-up Index [NDBI]) on the larvae abundance of Ae. aegypti and Ae. albopictus in Eldorado, Misiones, Argentina using remote satellite sensors. Larvae of these species were collected monthly (June 2016 to April 2018), in four environments: tire repair shops, cemeteries, dwellings and an urban natural park. The proportion of landscape coverage (water, urban areas, bare soil, low vegetation and high vegetation) was determined from the supervised classification of Sentinel-2 images and spectral indices, calculated. The authors developed spatial models of both vector species by generalized linear mixed models. The model's results showed that Ae. aegypti larvae abundance was better modelled by NDVI minimum values, NDBI maximum values and the interaction between them. For Ae. albopictus proportion of bare soil, low vegetation and the interaction between both variables explained better the abundance.

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Abstract Low biodiversity in urban areas is associated with habitat loss. However, the effects of urbanization on biodiversity should also consider the historical background of land-use, explored herein. Our goal was to evaluate changes in the assemblage of reptiles in an urban habitat over 100 years, aiming to identify which ecological attributes allowed the persistence of species that can be found in the area today. We accessed historical records in scientific collections and carried out fieldwork to access reptile assemblage in an urban green area, in São Paulo, Brazil. Considering land-use changes in the area, we defined three-time intervals between 1901 and 2020. We established species richness for each time interval, categorizing them into three ecological attributes: habitat preference, substrate use, and food habits. We recorded 27 reptile species from 1901 until 2020, 14 resulting from historical data, eight from both historical and fieldwork, and five species exclusively in fieldwork. Amphibians were also sampled during fieldwork, but not used in historical comparison. Reptile's species richness decreased 59% regardless of ecological attributes, and snakes were the group with most species' loss. Fossorial reptiles were the least affected group. We concluded that habitat loss culminated in a species richness decline, and the reptiles that remain until today were likely present since the fragment isolation. Ecological attributes of the remaining taxa include species that use terrestrial substrates and feed on prey commonly found in urban environments.

Resumo A baixa biodiversidade em áreas urbanas está associada à perda de habitat. No entanto, os efeitos da urbanização sobre a biodiversidade também devem considerar o histórico de uso da terra, explorado aqui. Nosso objetivo foi avaliar as mudanças na comunidade de répteis em um habitat urbano ao longo de 100 anos, visando identificar quais atributos ecológicos permitiram a persistência de espécies que podem ser encontradas na área hoje. Acessamos registros históricos em coleções científicas e realizamos trabalho de campo para levantar as espécies de répteis em uma área verde urbana, em São Paulo, Brasil. Considerando as mudanças de uso da terra na área amostrada, definimos três intervalos de tempo entre 1901 e 2020. Estabelecemos a riqueza de espécies para cada intervalo de tempo, categorizando-as em três atributos ecológicos: preferência de habitat, uso de substrato e hábitos alimentares. Registramos 27 espécies de répteis de 1901 até 2020, sendo 14 resultantes de dados históricos, oito de dados históricos e de campo e cinco espécies amostradas exclusivamente de campo. Anfíbios também foram amostrados durante o trabalho de campo, mas não foram usados na comparação histórica. A riqueza de espécies de répteis diminuiu 59% independentemente dos atributos ecológicos, e serpente foi o grupo com maior perda de espécies. Os répteis fossoriais foram o grupo menos afetado. Concluímos que a perda de habitat culminou em um declínio da riqueza de espécies, e os répteis que permanecem até hoje provavelmente estavam presentes desde o isolamento do fragmento. Os atributos ecológicos dos táxons remanescentes incluem espécies que utilizam substratos terrestres e se alimentam de presas comumente encontradas em ambientes urbanos.

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Low biodiversity in urban areas is associated with habitat loss. However, the effects of urbanization on biodiversity should also consider the historical background of land-use, explored herein. Our goal was to evaluate changes in the assemblage of reptiles in an urban habitat over 100 years, aiming to identify which ecological attributes allowed the persistence of species that can be found in the area today. We accessed historical records in scientific collections and carried out fieldwork to access reptile assemblage in an urban green area, in São Paulo, Brazil. Considering land-use changes in the area, we defined three-time intervals between 1901 and 2020. We established species richness for each time interval, categorizing them into three ecological attributes: habitat preference, substrate use, and food habits. We recorded 27 reptile species from 1901 until 2020, 14 resulting from historical data, eight from both historical and fieldwork, and five species exclusively in fieldwork. Amphibians were also sampled during fieldwork, but not used in historical comparison. Reptile’s species richness decreased 59% regardless of ecological attributes, and snakes were the group with most species’ loss. Fossorial reptiles were the least affected group. We concluded that habitat loss culminated in a species richness decline, and the reptiles that remain until today were likely present since the fragment isolation. Ecological attributes of the remaining taxa include species that use terrestrial substrates and feed on prey commonly found in urban environments.

A baixa biodiversidade em áreas urbanas está associada à perda de habitat. No entanto, os efeitos da urbanização sobre a biodiversidade também devem considerar o histórico de uso da terra, explorado aqui. Nosso objetivo foi avaliar as mudanças na comunidade de répteis em um habitat urbano ao longo de 100 anos, visando identificar quais atributos ecológicos permitiram a persistência de espécies que podem ser encontradas na área hoje. Acessamos registros históricos em coleções científicas e realizamos trabalho de campo para levantar as espécies de répteis em uma área verde urbana, em São Paulo, Brasil. Considerando as mudanças de uso da terra na área amostrada, definimos três intervalos de tempo entre 1901 e 2020. Estabelecemos a riqueza de espécies para cada intervalo de tempo, categorizando-as em três atributos ecológicos: preferência de habitat, uso de substrato e hábitos alimentares. Registramos 27 espécies de répteis de 1901 até 2020, sendo 14 resultantes de dados históricos, oito de dados históricos e de campo e cinco espécies amostradas exclusivamente de campo. Anfíbios também foram amostrados durante o trabalho de campo, mas não foram usados na comparação histórica. A riqueza de espécies de répteis diminuiu 59% independentemente dos atributos ecológicos, e serpente foi o grupo com maior perda de espécies. Os répteis fossoriais foram o grupo menos afetado. Concluímos que a perda de habitat culminou em um declínio da riqueza de espécies, e os répteis que permanecem até hoje provavelmente estavam presentes desde o isolamento do fragmento. Os atributos ecológicos dos táxons remanescentes incluem espécies que utilizam substratos terrestres e se alimentam de presas comumente encontradas em ambientes urbanos.

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Urban areas are expected to grow in the next decades, filtering bird species from the regional pool based on their life history traits. Although the impact of urbanization on traits such as diet, habitat and migratory behavior has been analyzed, their joint role with other traits related to plumage color has not yet been analyzed. Urban characteristics such as impervious surfaces, human presence and pollutants may be related to dark and uniform plumages. The objective of this study is to determine different bird species responses to urbanization using ordination analysis, and to characterize their life history traits combining information about diet, habitat and plumage color. Birds were surveyed along urban-rural gradients located in three cities of central Argentina. Species associations with urban characteristics were assessed through principal component analysis. Two axes were obtained: the first related positively to urban exploiters and negatively to urban avoiders, and a second axis related negatively to urban adapters. The scores of each axis were related to species traits through phylogenetic generalized least squares models. Species identified as 'urban exploiters' tended to nest in buildings and have uniform plumage, whereas those identified as 'urban avoiders' tended to be ground-nesting species with variable plumage. A third type, 'urban adapters', tended to be tree-nesting species with a low diet breadth, intermediate plumage lightness, low presence of plumage sexual dimorphism and high presence of iridescence. The results suggest that nest predation and habitat loss may exclude ground nesting birds from urban areas. The high density of pedestrians and domestic animals, such as cats and dogs, in urban centers may favor uniform plumages in birds that enhance camouflage.

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Anthropogenic noise and artificial light at night (ALAN) can disrupt the morning singing routines of urban birds, however, its influence on tropical species remains poorly explored. Here, I assessed the association between light and noise pollution with the dawn chorus onset of the Saffron Finch (Sicalis flaveola) in a city in Colombia. I studied 32 sites comprised of different conditions of urban development based on built cover. I recorded the time of the first song of the Saffron Finch, the conspecific density and measured anthropogenic noise and ALAN using smartphone apps. The findings of this study show that Saffron Finches living in highly developed sites sang earlier at dawn than those occupying less urbanized sites. Unexpectedly, this timing difference was related to ALAN instead of anthropogenic noise, suggesting that light pollution could drive earlier dawn chorus in a tropical urban bird. Saffron Finches could take advantage of earlier singing for signaling territorial ownership among neighbors. Future studies need to assess the influence of ALAN on the dawn chorus timing of Neotropical urban birds.

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Resumen En el presente trabajo se estudia la diversidad de escarabajos coprófagos en tres zonas urbanizadas del departamento de Sucre, Colombia, cada una con características ecológicas distintas. Los individuos fueron capturados con trampas de caída cebadas. Se analizaron el esfuerzo de muestreo, las curvas de rango-abundancia y los índices de diversidad alfa y beta. Se capturaron 710 individuos, agrupados en nueve géneros y 13 especies. El análisis de completitud arrojó valores por encima del 97%. El ensamble más diverso en cualquiera de los tres órdenes de "q" se encontró en la zona que alberga edificaciones, jardines y un parche de bosque de vegetación secundaria, seguido por una zona de pastizales, con pocas edificaciones; el ensamble de menor diversidad correspondió a la zona rodeada de edificaciones y con escasa cobertura vegetal. El índice de Sorensen-Dice arrojó una similitud total entre las tres zonas del 38%. Las curvas de rango-abundancia mostraron mayor equidad de especies en la zona más diversa. Los resultados indicaron que la composición del ensamble de escarabajos depende de las condiciones ambientales y el grado de urbanización. Así mismo, se evidenció que algunas especies pueden tener alta adaptabilidad y que algunas de ellas corren el riesgo potencial de presentar eventos de extinción local.

Abstract In this paper, diversity and composition of dung beetles assemblage was study in three urbanized areas with different ecological characteristics from Sucre department , Colombia. Individuals were captured with baited pitfall traps. Sampling effort, range-abundance curves, alpha and beta diversity indices were estimated and compared among the sites. Seven hundred ten individuals grouped into nine genera and 13 species were recorded. The completeness analysis yielded values above 97%. The most diverse assemblage in any of the three orders of "q" was found in the site with a mixture of buildings, gardens, and a patch of secondary vegetation forest, followed by the site with few facilities and open green spaces, and the least diverse site corresponded to the area surrounded by buildings with little vegetation cover. Sorensen-Dice index similarity among the three sites was 38%. The range-abundance curves showed higher species equitability in the most diverse site. The results show that the beetle assemblage composition depends on environmental conditions and the degree of urbanization. It was also evident that some species have high adaptability to urban spaces and others are potentially at risk of local extinction events.

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Big cities of Argentina are characterized by a strong social and economic fragmentation. This context enables the presence of urban rodents in close contact to the human population, mostly in the peripheral areas of the cities. Urban rodents can harbor a large variety of zoonotic pathogens. The aim of this study was to molecularly characterize Leptospira spp. and Bartonella spp. in urban rodents from the area of Gran La Plata, Buenos Aires province, Argentina. The species of urban rodents captured and tested were Rattus norvegicus, Rattus rattus, and Mus musculus. Leptospira interrogans and L. borgpetersenii were detected in R. norvegicus and M. musculus respectively. Bartonella spp. DNA was not detected in any of the kidney samples tested. No significant differences were observed between the prevalence of bacteria and rodent and environmental variables such as host sex, presence of stream and season by Generalized Linear Model analysis. These results confirm the role of urban rodents as infection sources of Leptospira spp., suggesting the need to implement public health measures to prevent the transmission of Leptospira spp. and other zoonotic pathogens from rodents to humans. Bartonella was not detected in this set of samples.

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