Global products of land use and land cover (LULC) provide maps with a consistent classification, thereby allowing for comparisons of resource and habitat use of species over large spatial scales. While global LULCs tend to be evaluated extensively, the distribution ranges of species can extend into remote areas that are hard to access for ground truthing. It is unclear how adequate global LULCs are for mapping habitat of long-distance migrants throughout their entire range. Here, we investigated whether different global LULCs could successfully capture the known preferences of a migratory wetland specialist, the Eurasian wigeon (Mareca penelope), along the East Atlantic flyway. We evaluated how well five different global LULC products captured known wigeon habitat preferences using remote tracking data, and tested whether a further classification based on wetland expert knowledge can improve on their performance. We found that average performance of global LULC products varied greatly, with ESA WorldCover performing best with a 94% correspondence to wigeon habitat. All products performed best in the Tundra biome, and worse in Boreal as well as Temperate forests. In the latter areas, our wetland expert LULC classification provided improved results by explicitly considering small and temporary wetlands, and wetlands underneath vegetation. Overall, habitat use of habitat specialists can inform us about habitat types that are currently not considered in large-scale LULC maps. We suggest LULC mapping methods integrate information from tracking of wetland specialists for a better detection of small and temporary wetlands on a global scale.

Sindbis virus (SINV) is a zoonotic arbovirus transmitted by mosquitoes and maintained by wild birds with an expanding distribution globally. Despite its importance, surveillance efforts are low or lacking in many areas, especially in Africa. Our study aimed to highlight the epidemiology of SINV in wild birds in a West African country - Nigeria - with implications for human health. Blood samples were collected from wild resident Afrotropical and migrant Palearctic birds over two years. RT-qPCR was used to detect SINV RNA positive samples, followed by confirmatory conventional PCR and Sanger sequencing targeting the non-structural protein gene. Three out of 504 samples (0.6%; 95% CI: 0.12-1.73%) were positive for SINV, all from individuals of a single species, the African Thrush (Turdus pelios). We successfully generated the whole genome sequence of one sample. Phylogenetic analysis revealed it was closely related to strains from Algeria, Spain and Kenya in the SINV-I genotype. The study suggests that SINV is enzootic in the region and that the African Thrush may be a putative reservoir species.

Migratory birds play a dual role as potential reservoirs of tick-borne pathogens, and potential dispersers of pathogen-containing ticks during their migratory journeys. Ixodes ricinus, a prevalent tick species in Northern and Western Europe, serves as a primary vector for Anaplasma phagocytophilum-a bacterium with implications for human and animal health. There is limited information available regarding A. phagocytophilum in birds. Our investigation focused on A. phagocytophilum prevalence in ticks collected from migratory birds in southeastern Sweden. The identification of ticks involved both molecular analyses for species determination and morphological classification to ascertain the developmental stage. The presence of A. phagocytophilum was determined using real-time PCR. Of the 1115 ticks analyzed from 4601 birds, 0.9% (n = 10), including I. ricinus and Ixodes frontalis, tested positive for A. phagocytophilum. Notably, common blackbirds (Turdus merula) yielded the highest number of A. phagocytophilum-infected ticks. The findings suggest that A. phagocytophilum is present in a small proportion of ticks infesting migratory birds in southeastern Sweden. Consequently, the role of birds as hosts for ticks infected with A. phagocytophilum appears to be low, suggesting that birds seem to play a minor indirect role in the geographic dispersal of A. phagocytophilum.

Wild passerine birds may serve as environmental reservoirs and as vectors for the long-distance dispersal of microorganisms and resistance determinants. However, there is no much knowledge on pathogenic bacteria in wild birds in Iran. The present study aimed to analyze antibiotic resistance in wild passerine birds collected from the northeast region of Iran as the rich breeding bird fauna with a special focus on Escherichia coli virulence, integron, and phylogenetic groups. A total of 326 isolates were collected and identified from the cloaca of wild birds using a swab. The results showed a high percentage of resistance to tetracycline (45.8%) and ampicillin (26.7%). The resistance genes, tet(A), tet(B), tet(M), and tet(L) were detected in tetracycline-resistant isolates, while the bla<inf>TEM</inf> gene was the most prevalent in ampicillin-resistant isolates (38.6%). Out of the 129 E. coli isolates examined, 99 isolates were found to have virulence gene, with the highest prevalence of the fimbriae (fimH) gene (22.4%). Additionally, the E. coli strains were most often classified into phylogenetic groups B1 (48.8%) followed by B2 (19.3%). Also, the highest average frequency of class 1 integron was detected among our isolates. Results indicated that wild birds are reservoirs of multidrug resistance and virulence genes that may have the potential to be transferred to other organisms, including humans. © 2024 Elsevier B.V., All rights reserved.

Wind energy development is a key component of climate change mitigation. However, birds collide with wind turbines, and this additional mortality may negatively impact populations. Collision risk could be reduced by informed selection of turbine dimensions, but the effects of turbine dimensions are still unknown for many species. As analyses of mortality data have several limitations, we applied a simulation approach based on flight height distributions of six European raptor species. To obtain accurate flight height data, we used high-frequency GPS tracking (GPS tags deployed on 275 individuals). The effects of ground clearance and rotor diameter of wind turbines on collision risk were studied using the Band collision risk model. Five species had a unimodal flight height distribution, with a mode below 25 m above ground level, while Short-toed Eagle showed a more uniform distribution with a weak mode between 120 and 260 m. The proportion of positions within 32–200 m ranged from 11 % in Marsh Harrier to 54 % in Red Kite. With increasing ground clearance (from 20 to 100 m), collision risk decreased in the species with low mode (−56 to −66 %), but increased in Short-toed Eagle (+38 %). With increasing rotor diameter (from 50 to 160 m) at fixed ground clearance, the collision risk per turbine increased in all species (+151 to +558 %), while the collision risk per MW decreased in the species with low mode (−50 % to −57 %). These results underpin that wind turbine dimensions can have substantial effects on the collision risk of raptors. As the effects varied between species, wind energy planning should consider the composition of the local bird community to optimise wind turbine dimensions. For species with a low mode of flight height, the collision risk for a given total power capacity could be reduced by increasing ground clearance, and using fewer turbines with larger diameter.

Objectives: The recent detection and expansion of West Nile virus (WNV) and Usutu virus (USUV) in the Netherlands, Germany, and Austria point to the likelihood of the viruses spreading to Northern Europe. Migratory birds and ornithophilic mosquitoes may spread these viruses to new areas. We sampled birds during the spring and autumn bird migration of 2021 in Southern Sweden to investigate the risk of the introduction of mosquito-borne zoonotic avian viruses like WNV and USUV.

Methods: We collected blood samples from 1775 birds comprising 59 species and determined the seroprevalence of WNV using a competitive enzyme-linked immunosorbent assay (ELISA). WNV and USUV belong to the Japanese encephalitis serocomplex, and antibodies against both viruses are detected in the WNV ELISA. Focus-forming assays or fluorescence-based neutralization assays were performed to verify ELISA results and to differentiate between antibodies against WNV and USUV.

Results: We found nine (0.51%) samples to be WNV-antibody-positive. Cross-neutralization experiments with WNV and USUV confirmed that seven (0.41%) had WNV-neutralizing antibodies and two (0.11%) had USUV-neutralizing antibodies. Interestingly, the two samples had neutralizing antibodies of both viruses. All samples but one with anti-flavivirus antibodies came from long-distance migrants wintering in sub-Saharan Africa. Antibodies were detected in samples taken during spring and autumn and only in adult birds.

Conclusion: The findings show that migratory birds in Sweden have been exposed to WNV and USUV. © 2025 Elsevier B.V., All rights reserved.

In recent decades, interest has grown in how increasing populations of herbivorous geese and swans (Anseriformes: Anatidae: Anserinae) affect macrophyte communities in wetlands, especially because many water-bodies are simultaneously subjected to stressors like eutrophication and biodiversity declines. Here, we review the literature on methods applied in grazing experiments that have been conducted in aquatic ecosystems. We also investigate and how different macrophyte characteristics may respond to waterfowl herbivory. Results indicate that both research methodology and responses of macrophytes differ widely among studies. While most experimental studies on grazing pressure employ a ‘paired plot design’ with exclosures and open control plots, the structure, size, and placement of plots vary among studies. Commonly sampled macrophyte variables are biomass (of either above- or below-ground plant parts), density, height, plant cover, and community composition. The literature provides support that geese and swans significantly affect several of these variables, but the outcome depends on additional factors, e.g. waterfowl density, water depth, and timing (within or between seasons/years). Because of the persisting conservation threats to aquatic ecosystems, more knowledge is needed about potential direct and indirect consequences of waterfowl herbivory in these environments.

De senaste årtiondena har intresset ökat för hur svanar och gäss påverkar växtligheten i våtmarker. För detta finns flera skäl. Ett är att flera arter av dessa fåglar har ökat kraftigt i antal, vissa också i utbredning. Många våtmarker hyser därför avsevärt fler av dessa stora växtätare än förut, i vissa fall fler än någonsin tidigare. Därtill är våtmarker föremål för andra förändringar, såsom eutrofiering, klimatförändringar, brunifiering och negativ utveckling hos delar av deras biologiska mångfald.I denna artikel ger vi en översikt av den vetenskapliga litteraturen om svanars och gäss bete på vattenvegetation. Dels har vi undersökt vilka undersökningsmetoder som vanligen används i experimentella studier, dels hur olika vegetationsvariabler svarar på bete. Vi finner att både undersökningsmetoder och växternas svar skiljer sig avsevärt mellan olika studier. Många experimentella studier av beteseffekter bygger på en kombination av uthägnade provytor och öppna kontrollytor i samma våtmark, alltså likartade ytor utan respektive med bete. Likväl är det ofta svårt att dra generella slutsatser av dessa studier eftersom provytornas antal, storlek och placering skiljer sig mycket åt. Än mer problematiskt är att användningen av olika mät- och provtagningsmetoder skiljer sig åt, vilket också försvårar jämförbarheten mellan studier. Vanliga vegetationsvariabler i jämförande studier är biomassa (ovan eller under markytan/bot-ten), täthet, höjd, täckningsgrad och artsammansättning hos växtsamhället. Tidigare forskning stöder uppfattningen att svanar och gäss på ett signifikant sätt kan påverka alla dessa variabler negativt. Graden av påverkan beror dock på olika andra faktorer, såsom vattendjup, tid på året och tätheten av växtätande fåglar. Med tanke på den tidigare och pågående kraftiga antropogena på-verkan på våtmarker är det viktigt att ytterligare studera direkta och indirekta effekter av svanars och gäss bete i våtmarksekosystem. 

Wild birds as source of pathogenic microorganisms infecting livestock and humans are an interesting topic that has received increased attention in recent years. Here we study occurrence of pathogenic bacteria in birds in north-east Iran with focus on to identifying virulence gene in wild and domestic birds. Wild birds were trapped and sampled in different localities in northeast Iran from April to September in 2018 and 2019. From 184 birds representing 32 species of wild passerine birds, potentially pathogenic bacteria were isolated from 171 samples (92.9). Escherichia coli was the most frequently isolated bacterium with a prevalence of 70.1%, followed by Enterobacter spp. (53.8%) and Salmonella spp (3.2%) isolated from 129, 99 and 6 wild birds, respectively. In total 79.6% of the isolates carried virulence factors. A higher frequency of virulence genes was detected in domestic birds (88.6%) than in wild birds (76%). The results showed that birds in north-east Iran can serve as a potential source of bacterial pathogens and virulence factors that may cause disease in both humans and birds. Furthermore, our results introduce new host birds as source of pathogenic microorganisms that can carry and disseminate them in the environment. © 2024 Elsevier B.V., All rights reserved.

Humans are radically altering global ecology, and one of the most apparent human-induced effects is urbanization, where high-density human habitats disrupt long-established ecotones. Changes to these transitional areas between organisms, especially enhanced contact among humans and wild animals, provide new opportunities for the spread of zoonotic pathogens. This poses a serious threat to global public health, but little is known about how habitat disruption impacts cross-species pathogen spread. Here, we investigated variation in the zoonotic enteric pathogen Campylobacter jejuni. The ubiquity of C. jejuni in wild bird gut micro- biomes makes it an ideal organism for understanding how host behavior and ecology influence pathogen transition and spread. We analyzed 700 C. jejuni isolate genomes from 30 bird species in eight countries using a scalable generalized linear model approach. Comparing multiple behavioral and ecological traits showed that proximity to human habitation promotes lineage diversity and is associated with antimicrobial-resistant (AMR) strains in natural populations. Specifically, wild birds from urban areas harbored up to three times more C. jejuni genotypes and AMR genes. This study provides novel methodology and much-needed quantitative evidence linking urbanization to gene pool spread and zoonoses.