Filters
No evidence for potential sexual information from a monochromatic carotenoid trait in a dichromatic woodpecker species
A survey targeting exotic Aedes mosquito species in Central Europe, summer 2023, reveals the extensive occurrence of Aedes japonicus in Poland
Abstract In the frame of the entomological VectorNet network and its capacity building activities, we collected original mosquito distribution data in southern Poland and bordering areas of the Czech Republic, Germany and Slovakia, in June and September–November 2023. Because of the suspected occurrence of Aedes japonicus or Ae. koreicus in Poland, provided by a photo posted early 2022 on iNaturalist, we targeted the exotic Aedes species in our sampling strategy, but also collected data on other mosquito species. Besides some adult catches, we mainly collected mosquito immature stages from artificial and natural water containers but occasionally from other aquatic habitats. In addition, we collated citizen data and modelled the distribution of Ae. japonicus in Europe incorporating the newly collected data. During this snapshot field study, a total of 162 samples, including 139 yielding mosquitoes, were taken from 111 locations across 47 administrative units, resulting on the detection of 22 mosquito taxa. Our study provides the first substantiated records of Ae. japonicus and Anopheles petragnani in Poland (the second confirmed by molecular identification). While Ae. japonicus is clearly established over a large part of the country, no other exotic mosquito species was detected. The presence of Ae. japonicus was also confirmed at one location by four citizen records submitted to MosquitoAlert in 2023. Regarding native mosquitoes, we identified their presence in 127 species/NUTS3 combinations (113 for Poland, including a single record for An. petragnani). An updated modelling of the distribution of Ae. japonicus suggests higher environment suitability in Central and Eastern Europe than has been previously estimated. Aedes japonicus is probably widespread in the Czech Republic and Slovakia, and might soon colonise the bordering region of Ukraine. Its establishment extends the putative mosquito vector list for West Nile and Rift Valley fever viruses in Central Europe.
Impact of bisphenol A and ethinyloestradiol on sex, body condition and digit ratio of the marsh frog Pelophylax ridibundus in the mesocosm exposure system
Investigating Sexual Characteristics in Two Frog Species Under Exposure to River Water Polluted with Endocrine Disruptors
Endocrine-disrupting compounds (EDCs) are emerging environmental pollutants that are known to the disrsupt hormonal system of many vertebrates. Amphibians, with their aquatic larval stages and high sensitivity to waterborne contaminants, are especially vulnerable to EDC exposure. Despite increasing concerns over EDC pollution, systematic monitoring of these compounds in surface waters remains limited in many regions, including the European Union. This study investigates the effects of water from the Warta River, one of the largest rivers in Central Europe, an urban waterway subjected to significant anthropogenic pressure and known to contain EDCs on body condition, digit ratio, and gonadal development in two brown frog species: the common frog Rana temporaria and the moor frog Rana arvalis. We propose DR as a potential biomarker of endocrine disruption, as it is linked to hormonal impact in the early development of vertebrates. In this study, tadpoles were reared in the semi-open experimental setup with tanks containing river or potable tap water as a control. Contrary to expectations, no significant differences were observed in body condition, digit ratio, or gonadal structure, suggesting that EDC concentrations in the river water may not have been high enough to induce detectable effects. However, a consistent relation between DR and sex was observed in both species, underscoring its potential as a biologically meaningful trait. Notably, the potable tap water used as a control exhibited contamination levels comparable to the river water, raising concerns about the efficacy of current water treatment methods and highlighting the challenges of establishing true reference conditions in environmental studies.
Wild bee larval food composition in five European cities
AbstractUrbanization poses threats and opportunities for the biodiversity of wild bees. At the same time, cities can harbor diverse wild bee assemblages, partly due to the unique plant assemblages that provide resources. While bee dietary preferences have been investigated in various studies, bee dietary studies have been conducted mostly in nonurban ecosystems and data based on plant visitation observations or palynological techniques. This data set describes the larval food preferences of four wild bee species (i.e., Chelostoma florisomne, Hylaeus communis, Osmia bicornis, and O. cornuta) common in urban areas in five different European cities (i.e., Antwerp, Belgium; Paris, France; Poznan, Poland; Tartu, Estonia; and Zurich, Switzerland). In addition, the data set describes the larval food preferences of individuals from three wild bee genera (i.e., Chelostoma sp., Hylaeus sp., and Osmia sp.) that could not be identified to the species level. These data were obtained from a Europe‐level study aimed at understanding the effects of urbanization on biodiversity across different cities and cityscapes and a Swiss project aimed at understanding the effects of urban ecosystems in wild bee feeding behavior. Wild bees were sampled using standardized trap nests at 80 sites (32 in Zurich and 12 in each of the remaining cities), selected following a double gradient of available habitat at local and landscape scales. Larval pollen was obtained from the bee nests and identified using DNA metabarcoding. The data provide the plant composition at the species or genus level preferred by each bee. These unique data can be used for a wide array of research questions, including urban ecology (e.g., diversity of food sources along urban gradients), bee ecology (characterization of bee feeding preferences), or comparative studies on the urban evolution of behavioral traits between urban and nonurban sites. In addition, the data can be used to inform urban planning and conservation strategies, particularly concerning flower resources (e.g., importance of exotic species and, thus, management activities). This data set can be freely used for noncommercial purposes, and this data paper should be cited if the data is used; we request that collaboration with the data set contact person to be considered if this data set represents an important part of the data analyzed in a study.
White stork Ciconia ciconia nests as an attractant to birds and bats
AbstractWhite storks (Ciconia ciconia), an emblematic bird of high conservation interest, build massive nests which are also important breeding sites for other birds. However, their role as a potential source of food for foraging birds and bats is unexplored. In this study, we counted insectivorous aerially foraging birds (swallows, martins, and swifts), sparrows, and bats foraging around 51 pairs of white storks’ nest and control sites in Poland. The number of birds was significantly higher near active white stork nests than control sites, but this effect was invisible for bats. White storks provide important benefits to the conservation of co-occurring species.
Overwintering Culex torrentium in abandoned animal burrows as a reservoir for arboviruses in Central Europe
Opportunities and Limitations of Molecular Methods for Studying Bat-Associated Pathogens
Bats have been identified as reservoirs of zoonotic and potentially zoonotic pathogens. Significant progress was made in the field of molecular biology with regard to infectious diseases, especially those that infect more than one species. Molecular methods, sequencing and bioinformatics have recently become irreplaceable tools in emerging infectious diseases research and even outbreak prediction. Modern methods in the molecular biology field have shed more light on the unique relationship between bats and viruses. Here we provide readers with a concise summary of the potential and limitations of molecular methods for studying the ecology of bats and bat-related pathogens and microorganisms.
Urban intensity gradients shape community structure, life‐history traits and performance in a multitrophic system
Abstract Urban ecosystems are formed by pronounced socio‐ecological gradients, which are distinct from other ecosystems and can simultaneously filter and promote taxa, ultimately affecting their interactions. However, the strength of the effect of filtering and facilitation across the different trophic levels could vary among biotic and abiotic factors. Here, we investigate the effects of habitat amount, temperature and host‐enemy biotic interactions in shaping communities of cavity‐nesting bees and wasps and their natural enemies. We installed trap‐nests in 80 sites distributed along urban intensity gradients in five European cities (Antwerp, Paris, Poznan, Tartu and Zurich). We quantified the species richness and abundance of hosts and their natural enemies, as well as two performance traits (survival and parasitism) and two life‐history traits (sex ratio and number of offspring per nest for the hosts). We analysed the importance of the abiotic and biotic variables using generalised linear models and multi‐model inference. We found that habitat amount was the main driver of multiple host responses, with larger habitat amounts resulting in higher species richness and abundance for hosts and natural enemies, as well as a larger probability of survival and a larger number of brood cells for hosts. Local resources proxies shaped both bees and wasps and indicate different uses of existing vegetation between bees and wasps. Temperature proxies had a minor role in shaping host and natural enemies. Biotic interactions were a main driver of host and enemy community structure, with natural enemies being strongly affected by host availability, that is, with direct density‐dependence between hosts and their natural enemies. Overall, our study highlights the importance of habitat amount and temperature in shaping urban food webs, as well as on biotic interactions through direct effects on hosts responses and the subsequent consequences for their natural enemies. As cities prepare to tackle the consequences of global change, strategies that make it possible to maintain habitat and mitigate urban overheating emerge as a key urban adaptation for biodiversity conservation.