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Studies on avian haemosporidians in Mexico and around the world reveal poor knowledge about the vectors that transmit avian haemosporidian parasites and their association with vertebrate hosts. Seasonal variations given by changes in temperature and precipitation have significant repercussions on the dynamics of vector-borne infections. The seasonal dynamics of major haemosporidian parasites and their main vectors are mostly unknown. This study aimed to determine the presence of avian haemosporidians in hematophagous mosquitoes and to characterize mosquito-vertebrate host interactions during a year in a peri-urban cloud forest in Xalapa City, Veracruz, Mexico. We analyzed 12 species and a total of 1170 hematophagous mosquitoes. We found the presence of Plasmodium and Haemoproteus genera in the blood meals of mosquitoes. The highest haemosporidian detection and mosquito richness were in June (dry-warm season), whereas the highest mosquito abundance was in October (humid-warm season). We recorded three new haemosporidian lineages in this study. Analysis of blood meals showed that mosquitoes fed on different vertebrate groups (amphibians, reptiles, birds, and humans). This study contributed to the knowledge about the distribution of hematophagous mosquito-haemosporidian-vertebrate host interactions., Competing Interests: Declarations Ethical approval Ethical Approval (applicable for both human and/ or animal studies). Ethical committees, Internal Review Boards and guidelines followed must be named. Consent to participate and Consent to publish Consent to participate and consent to publish in statements in accordance with ethical standards do not apply to this work. Competing interest The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this study we focused on urban bird diversity across Mexico, a megadiverse country, with a special focus on the relative role of urban greenspaces and heavily-built sites. We considered a country-wide approach, including 24 different sized Mexican cities. Our aims were to describe the urban bird diversity in focal cities and further assess the relationships between it and the biogeographic region where cities are located, their size, elevation, and annual rainfall. Additionally, we evaluated differences in the functional composition of bird communities in both studied urban scenarios (i.e., urban greenspaces, heavily-built sites). Our results confirm that urban greenspaces are home to a large proportion of species when contrasted with heavily-built sites. While total species richness and species richness of greenspaces were related with the cities' biogeographic region -with higher species richness in the Neotropical region and Transition Zone-, the relationship did not hold true in heavily-built sites. We found that annual rainfall was negatively related to bird richness in heavily-built sites, suggesting that species from arid systems can be more tolerant to urbanization. Regarding the bird functional group assessment, results show a clear differentiation between the functional groups of greenspaces and those of heavily-built sites, with granivores and omnivores associated with the latter and a highly diverse array of functional groups associated with urban greenspaces., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2020. Published by Elsevier B.V.)

This investigation was undertaken to determine the concentrations of lead in bird blood samples from a mining region in central Mexico and to compare concentrations among several different feeding guilds. The study took place in the Mexican state of San Luis Potosi in a region known as "Villa de la Paz." This is one of the most intensely exploited mining regions in central Mexico and has been actively mined for over four centuries. Lead concentrations from bird blood samples taken from four polluted sites were significantly higher than those from a control, unpolluted site (F = 6.3, P < 0.0002). Similarly, mean blood lead concentrations in birds from a highly polluted site were higher than those from a site that has intermediate pollution levels (P < 0.05). In addition, samples from insectivorous birds had significantly lower lead concentrations compared to granivores, frugivores-insectivores, and omnivores (F = 4.86, P = 0.004), and a large proportion of all individuals had blood lead concentrations indicative of low, sub-lethal toxic effects. Finally, in two polluted sites, remarkably small numbers of insectivore-frugivores, and granivores were trapped, and in one polluted site a large number of insectivores was trapped (X(2) = 29.9, P = 0.03), and no differences in proportions of migrants and non-migrants were found among sampling sites (X(2) = 0.6, P = 0.96). To date, it has not been determined to what extent constant exposure to these levels of pollution can influence health at the individual level, lifespan, and, therefore, population demography of birds from this region.