Turdus Merula Research Articles

RECORDS OF IXODID TICKS ON WILD BIRDS IN BULGARIA

Background: Ixodid ticks are widely studied due to their epidemiological and epizootic importance. It is of great value to know vertebrate host preferences of ticks in order to understand their ecological relationships and distribution. Earlier studies report birds as important hosts of Ixodid tick and a total of 136 ticks species have been frequently found in birds worldwide. However, only few studies related to host preferences of ticks among wild birds in Bulgaria were conducted till now. Aim: To obtain new data on the host preferences of ixodid ticks among wild birds at three locations in Bulgaria. Material and methods: The study was conducted between 2010 – 2020 in three sites in Bulgaria – Biological Experimental Station Kalimok (Silistra region), near Brodilovo village (Burgas region), and the city of Sofia (city park). The birds were caught by mist nets and inspected for ticks. Ticks found were removed by fine tweezers or a special removal tool for ectoparasites. Tick identification was based on external morphological characteristics. Results: A total of 2419 individual birds belonging to 78 species were examined. Of these, 70 individuals (16 species) carried ticks, thus representing 2.9% infestation rate. A total of 262 ticks were collected and identified as: Ixodes ricinus, Hyalomma marginatum, Haemaphysalis punctata, Hae. concinna, Hae. sulcata and two specimens could only be identified to the genus Haemaphysalis. Ixodes ricinus was the most commonly encountered tick (224/262), predominantly nymphs, followed by Hyalomma marginatum (27/262). The highest prevalence of tick infestation was observed among the Eurasian Blackbird, Turdus merula (28.6%), followed by the common nightingale, Luscinia megarhynchos (12.9%) and the common chaffinch, Fringilla coelebs (11.3%). These three bird species harboured the majority of ticks on their heads – some single individuals were infested by 10 up to 25 ticks per bird. Conclusion: Ixodes ricinus was found as the predominant tick species in this study. Nymphs were the most frequently observed stage. Infesting both birds and humans, this tick species has the potential to spread local tick-borne infections.

Pathology and Pathogenesis of Eurasian Blackbirds (Turdus merula) Naturally Infected with Usutu Virus.

The Usutu virus (USUV) is a mosquito-borne zoonotic flavivirus. Despite its continuous circulation in Europe, knowledge on the pathology, cellular and tissue tropism and pathogenetic potential of different circulating viral lineages is still fragmentary. Here, macroscopic and microscopic evaluations are performed in association with the study of cell and tissue tropism and comparison of lesion severity of two circulating virus lineages (Europe 3; Africa 3) in 160 Eurasian blackbirds (Turdus merula) in the Netherlands. Results confirm hepatosplenomegaly, coagulative necrosis and lymphoplasmacytic inflammation as major patterns of lesions and, for the first time, vasculitis as a novel virus-associated lesion. A USUV and Plasmodium spp. co-infection was commonly identified. The virus was associated with lesions by immunohistochemistry and was reported most commonly in endothelial cells and blood circulating and tissue mononucleated cells, suggesting them as a major route of entry and spread. A tropism for mononuclear phagocytes cells was further supported by viral labeling in multinucleated giant cells. The involvement of ganglionic neurons and epithelial cells of the gastrointestinal tract suggests a possible role of oral transmission, while the involvement of feather follicle shafts and bulbs suggests their use as a diagnostic sample for live bird testing. Finally, results suggest similar pathogenicity for the two circulating lineages.

Emerging Trends in the West Nile Virus Epidemiology in Croatia in the 'One Health' Context, 2011-2020.

West Nile virus (WNV) is one of the most widely distributed (re-)emerging arboviruses. In Croatia, acute WNV infections as well as seropositivity were detected in humans, horses, birds and poultry. Although serologic evidence of WNV human infections dates back to the 1970s, no clinical cases were reported until 2012. WNV outbreaks, as well as sporadic infections, were continuously recorded in continental Croatian counties from 2012 to 2018. In addition, acute asymptomatic infections (IgM antibodies) in horses have been regularly notified in continental regions since 2012, while seropositive horses (seroprevalence rates 3.7–21.4%) were detected in both continental and coastal regions. Moreover, WNV seropositivity in poultry (1.8–22.9%) was reported from 2013 to 2020. During the largest WNV outbreak in 2018, WNV RNA was detected for the first time in two dead goshawks (Accipiter gentilis) from the same aviary in North-West Croatia, while WNV antibodies were found in one buzzard (Butteo butteo) from the same region. In addition, WNV RNA was detected in a dead blackbird (Turdus merula) at the Croatian littoral. The phylogenetic analysis of 11 strains detected in urine samples of patients with neuroinvasive disease and 1 strain detected in a goshawk showed circulation of WNV lineage 2. Thus far, WNV has not been detected in mosquitoes in Croatia.

Breeding Performances of the European Blackbird (Turdus merula) in Morocco: Habitat Selection, Breeding Phenology, and Breeding Success

The European Blackbird (Turdus merula) is a widespread species. In Morocco, available knowledge on this species is limited to a few descriptive pieces of information with no detailed data provided. With climate change and the intensification of agricultural activities, the study of the breeding performances of this species is indispensable for management purposes. This study investigates breeding biology, nesting habitats, breeding chronology, and reproductive success of the European Blackbird in both apple orchards and surrounding woody vegetation at Ait Ayach (Morocco) between March and August 2016. We monitored weekly nest status, nesting sites, breeding dates, and failure factors. Results showed that the European Blackbird nests mainly in apple orchards, on Golden Delicious and Starkrimson Delicious trees. Nest height above the ground was 214.15 ± 0.09 cm. Blackbird nests were cup-shaped with medium size dimensions and built from twigs, including dry leaves, stems, and roots walled by the mud. Breeding activities started firstly by nest construction during the last week of April, secondly by egg laying during the first week of May, and thirdly by hatching during the second week of May. Among the 74 surveyed nests, 100% were active during the nesting phase and 88.38% of eggs have succeeded during the incubation phase. In total, 69.03% of chicks have been emancipated. In short, 15.9% of clutches were attacked by predators, 14.35% of clutches were failed due to nest desertion, and 8.75% of chicks were dead. Our study provides the first and only detailed data on reproductive parameters of the European Blackbird in Moroccan ecosystems. Data collected from this study provide valuable information for long-term monitoring of the Moroccan Blackbird population. Additionally, our data offer a possibility of large-scale comparative studies of the reproductive ecology of the Blackbird species.

West Nile and Usutu Viruses' Surveillance in Birds of the Province of Ferrara, Italy, from 2015 to 2019.

West Nile (WNV) and Usutu (USUV) viruses are mosquito-borne flaviviruses. Thanks to their importance as zoonotic diseases, a regional plan for surveillance of Arboviruses was implemented in Emilia-Romagna in 2009. The province of Ferrara belongs to the Emilia-Romagna region, and it is an endemic territory for these viruses, with favorable ecological conditions for abundance of mosquitoes and wild birds. From 2015 to 2019, we collected 1842 dead-found birds at a wildlife rehabilitation center, which were analysed by three different PCRs for the detection of WNV and USUV genomes. August was characterized by the highest infection rate for both viruses. Columbiformes scored the highest USUV prevalence (8%), while Galliformes and Strigiformes reported the highest prevalence for WNV (13%). Among Passeriformes (the most populated Order), Turdus merula was the most abundant species and scored the highest prevalence for both viruses. To optimize passive surveillance plans, monitoring should be focused on the summer and towards the avian species more prone to infection by both viruses.

A songbird adjusts its heart rate and body temperature in response to season and fluctuating daily conditions.

In a seasonal world, organisms are continuously adjusting physiological processes relative to local environmental conditions. Owing to their limited heat and fat storage capacities, small animals, such as songbirds, must rapidly modulate their metabolism in response to weather extremes and changing seasons to ensure survival. As a consequence of previous technical limitations, most of our existing knowledge about how animals respond to changing environmental conditions comes from laboratory studies or field studies over short temporal scales. Here, we expanded beyond previous studies by outfitting 71 free-ranging Eurasian blackbirds (Turdus merula) with novel heart rate and body temperature loggers coupled with radio transmitters, and followed individuals in the wild from autumn to spring. Across seasons, blackbirds thermoconformed at night, i.e. their body temperature decreased with decreasing ambient temperature, but not so during daytime. By contrast, during all seasons blackbirds increased their heart rate when ambient temperatures became colder. However, the temperature setpoint at which heart rate was increased differed between seasons and between day and night. In our study, blackbirds showed an overall seasonal reduction in mean heart rate of 108 beats min-1 (21%) as well as a 1.2°C decrease in nighttime body temperature. Episodes of hypometabolism during cold periods likely allow the birds to save energy and, thus, help offset the increased energetic costs during the winter when also confronted with lower resource availability. Our data highlight that, similar to larger non-hibernating mammals and birds, small passerine birds such as Eurasian blackbirds not only adjust their heart rate and body temperature on daily timescales, but also exhibit pronounced seasonal changes in both that are modulated by local environmental conditions such as temperature. This article is part of the theme issue 'Measuring physiology in free-living animals (Part I)'.

Sex and age, but not blood parasite infection nor habitat, affect the composition of the uropygial gland secretions in European blackbirds

The uropygial gland of birds produces an oily secretion with different functions, mainly related to plumage protection. In addition, the volatile compounds of this secretion may act as chemical signals that provide information to conspecifics, but it is also possible that those compounds may further attract hematophagous insect vectors such as those responsible for avian malaria transmission. Individual characteristics such as sex and age are usually associated with variation in the composition of the uropygial secretion. Different studies have shown that mosquitoes are more attracted towards birds infected by avian malaria parasites. However, whether the individual infection status by these parasites may lead to differences in the composition of this secretion remains poorly known. We used gas chromatography–mass spectrometry (GC–MS) to characterise the chemical composition of the volatile lipophilic fraction of the uropygial gland secretions of wild European blackbirds and compare its composition in an urban and a forest locality according to their age, sex and infection status by blood parasites. We found differences in the composition of the secretion between age classes and also between sexes within adult birds. However, no differences were found in the chemical composition of the uropygial gland secretion of birds according to their infection status by blood‐parasites and habitat type. These results suggest that haemosporidian infection does not alter the composition of the volatile fraction of uropygial gland secretions in infected birds.

A Sentinel Serological Study in Selected Zoo Animals to Assess Early Detection of West Nile and Usutu Virus Circulation in Slovenia.

Monitoring infectious diseases is a crucial part of preventive veterinary medicine in zoological collections. This zoo environment contains a great variety of animal species that are in contact with wildlife species as a potential source of infectious diseases. Wild birds may be a source of West Nile virus (WNV) and Usutu (USUV) virus, which are both emerging pathogens of rising concern. The aim of this study was to use zoo animals as sentinels for the early detection of WNV and USUV in Slovenia. In total, 501 sera from 261 animals of 84 animal species (including birds, rodents, lagomorphs, carnivores, ungulates, reptiles, equids, and primates) collected for 17 years (2002–2018) were tested for antibodies to WNV and USUV. Antibodies to WNV were detected by indirect immunofluorescence tests in 16 (6.1%) of 261 animals representing 10 species, which were sampled prior to the first active cases of WNV described in 2018 in Slovenia in humans, a horse, and a hooded crow (Corvus cornix). Antibodies to USUV were detected in 14 out of 261 animals tested (5.4%) that were positive prior to the first positive cases of USUV infection in common blackbirds (Turdus merula) in Slovenia. The study illustrates the value of zoological collections as a predictor of future emerging diseases.

Effects of mammal exclusion on invertebrate communities in New Zealand

AbstractIn the absence of mammals, the fauna of islands is characterised by high endemism levels and a tendency towards gigantism, flightlessness and longevity. These characteristics have resulted in a high vulnerability to introduced animals, either directly via predation or indirectly through an alteration of food web interactions. Because invertebrates are important components of food webs and essential for many ecosystem processes, we investigated how different mammal and bird communities, present inside and outside a fenced reserve, influenced ground‐dwelling invertebrates on the mainland of New Zealand. Some significant differences in invertebrate community composition were apparent inside versus outside the fenced reserve, predominantly Ctenognathus adamsi (Carabidae) being twenty times more abundant inside the reserve, and rove beetles (Staphylinidae) being eight times more abundant outside the reserve. The introduced blackbird (Turdus merula) was observed more regularly than other predators of invertebrates outside the reserve, while native robins (Petroica longipes) were more highly detected inside the reserve. Despite differences in the vertebrate insectivore community outside the reserve (multiple mammals and introduced birds) compared to inside (mainly native birds), the resulting similarity in net predation pressure may explain the apparent similarity in abundance for most of the other 24 invertebrate taxa examined. Removal of most mammals from within fenced reserves in New Zealand may enable introduced and native birds to flourish, with flow‐on effects on the invertebrate community. We conclude that further study of trophic interactions and additional intervention, may need to be considered if invertebrate conservation is a desired outcome from fenced reserves.

Effects of stress exposure in captivity on physiology and infection in avian hosts: no evidence of increased Borrelia burgdorferi s.l. infectivity to vector ticks.

Exposure to environmental stressors, an increasingly recurring event in natural communities due to anthropogenic-induced environmental change, profoundly impacts disease emergence and spread. One mechanism through which this occurs is through stress-induced immunosuppression increasing disease susceptibility, prevalence, intensity and reactivation in hosts. We experimentally evaluated how exposure to stressors affected both the physiology of avian hosts and the prevalence of the zoonotic bacteria Borrelia burgdorferi sensu lato (s.l.), in two model species-the blackbird Turdus merula and the robin Erithacus rubecula captured in the wild, using xenodiagnoses and analysis of skin biopsies and blood. Although exposure to stressors in captivity induced physiological stress in birds (increased the number of circulating heterophils), there was no evidence of increased infectivity to xenodiagnostic ticks. However, Borrelia detection in the blood for both experimental groups of blackbirds was higher by the end of the captivity period. The infectivity and efficiency of transmission were higher for blackbirds than robins. When comparing different methodologies to determine infection status, xenodiagnosis was a more sensitive method than skin biopsies and blood samples, which could be attributed to mild levels of infection in these avian hosts and/or dynamics and timing of Borrelia infection relapses and redistribution in tissues.

The effects of parental age difference on the offspring sex and fitness of European blackbirds.

BackgroundMany studies of birds have indicated that offspring sex ratios can vary with environmental and parental traits. On the basis of long-term research, we first evaluated the possible influence of parental age difference and brood characteristics on offspring sex and fitness in multi-brooded Blackbirds Turdus merula.MethodologyThe study was conducted in the city-centre Stefan Żeromski Park in Szczecin, NW Poland, where the local population of Blackbirds has been studied since 1996. Data on the offspring sex and fitness were collected in five years, 2005–2007 and 2016–2017. During the breeding season we inspected the study area to locate the pairs’ territories and to track their nests and clutches.ResultsWe found that the overall sex ratio did not differ statistically from 50:50, but that younger females bonded with older mates did tend to produce more sons, probably because of the greater fitness of male descendants. Accordingly, the sons’ breeding success increased with the father’s age, but this relationship was close to non-linear, which may indicate that the transgenerational effect of paternal senescence could negatively affect progeny fitness despite the high-quality of older fathers. Older females mated with younger males produced more daughters, which could have been due to the lesser attractiveness of the males and the mothers’ poorer condition caused by accelerated senescence. We found that neither offspring hatching sequence nor hatching date or clutch sequence were significant for sex determination.ConclusionsWe consider that in our Blackbird population, parental age could make a more significant contribution to shaping offspring sex and reproductive success.

DETECTION OF HERPESVIRUSES IN PASSERINE BIRDS CAPTURED DURING AUTUMN MIGRATION IN SLOVENIA.

Herpesviruses (HVs) were detected by PCR in the cloacal swabs of 0.76% (4/525) clinically healthy free-living passerine birds from 32 different species captured in mist nets in Slovenia during the 2014 and 2017 autumn migrations. Herpesviruses were detected in the Eurasian Blackcap (Sylvia atricapilla), the Common Blackbird (Turdus merula), and the Eurasian Blue Tit (Cyanistes caeruleus). Phylogenetic analysis of partial DNA polymerase gene nucleotide sequences of the HV strains showed a distant relationship with other alphaherpesviruses of birds. In the phylogenetic tree, the HVs detected were clustered together with HV detected in Sulphur-crested Cockatoo and Neotropic Cormorants, as well as with known HVs such as gallid HV1, psittacid HV1 and HV2, and passerine HV1. Different sequences of HVs with relatively low identity were detected in our study, suggesting that different HVs were circulating in passerines sampled during the autumn migration in Slovenia.

A Bacterially-Expressed Recombinant Envelope Protein from Usutu Virus Induces Neutralizing Antibodies in Rabbits.

Background: Recently, an emerging flavivirus, Usutu virus (USUV), has caused an epidemic among birds in Europe, resulting in a massive die-off in Eurasian blackbirds. Currently found only in Europe and Africa, it can be envisioned that Usutu virus will follow the path of other flaviviruses, like West Nile virus and Zika virus, and will spread via its mosquito vectors and bird hosts to other parts of the world. Several cases of human infections by Usutu virus have already been published. Anticipating this spread, development of an efficacious vaccine would be highly desirable. Method: This study describes the production in E. coli, purification, and refolding of a partial USUV envelope protein. Prior to immunization, the protein was characterized using size exclusion chromatography, transmission electron microscopy and dynamic light scattering, showing the limited presence of virus-like structures, indicating that the protein solution is probably a mixture of mono and multimeric envelope proteins. Results: Immunizations of two rabbits with the refolded E-protein fraction, mixed with a strong adjuvant, resulted in the generation of neutralizing antibodies, as evidenced in an in vitro assay. Discussion: The way forward towards a subunit vaccine against Usutu virus infection is discussed.

Comparative Mapping of the Macrochromosomes of Eight Avian Species Provides Further Insight into Their Phylogenetic Relationships and Avian Karyotype Evolution

Avian genomes typically consist of ~10 pairs of macro- and ~30 pairs of microchromosomes. While inter-chromosomally, a pattern emerges of very little change (with notable exceptions) throughout evolution, intrachromosomal changes remain relatively poorly studied. To rectify this, here we use a pan-avian universally hybridising set of 74 chicken bacterial artificial chromosome (BAC) probes on the macrochromosomes of eight bird species: common blackbird, Atlantic canary, Eurasian woodcock, helmeted guinea fowl, houbara bustard, mallard duck, and rock dove. A combination of molecular cytogenetic, bioinformatics, and mathematical analyses allowed the building of comparative cytogenetic maps, reconstruction of a putative Neognathae ancestor, and assessment of chromosome rearrangement patterns and phylogenetic relationships in the studied neognath lineages. We observe that, as with our previous studies, chicken appears to have the karyotype most similar to the ancestor; however, previous reports of an increased rate of intrachromosomal change in Passeriformes (songbirds) appear not to be the case in our dataset. The use of this universally hybridizing probe set is applicable not only for the re-tracing of avian karyotype evolution but, potentially, for reconstructing genome assemblies.

The Role of Peridomestic Animals in the Eco-Epidemiology of Anaplasma phagocytophilum.

Anaplasma phagocytophilum is an important tick-borne zoonotic agent of human granulocytic anaplasmosis (HGA). In Europe, the Ixodes ticks are the main vector responsible for A. phagocytophilum transmission. A wide range of wild animals is involved in the circulation of this pathogen in the environment. Changes in populations of vertebrates living in different ecosystems impact the ecology of ticks and the epidemiology of tick-borne diseases. In this study, we investigated four species, Western European hedgehog (Erinaceus europaeus), northern white-breasted hedgehog (Erinaceus roumanicus), Eurasian red squirrel (Sciurus vulgaris), and the common blackbird (Turdus merula), to describe their role in the circulation of A. phagocytophilum in urban and periurban ecosystems. Ten different tissues were collected from cadavers of the four species, and blood and ear/skin samples from live blackbirds and hedgehogs. Using qPCR, we detected a high rate of A. phagocytophilum: Western European hedgehogs (96.4%), northern white-breasted hedgehogs (92.9%), Eurasian red squirrels (60%), and common blackbirds (33.8%). In the groEL gene, we found nine genotypes belonging to three ecotypes; seven of the genotypes are associated with HGA symptoms. Our findings underline the role of peridomestic animals in the ecology of A. phagocytophilum and indicate that cadavers are an important source of material for monitoring zoonotic pathogens. Concerning the high prevalence rate, all investigated species play an important role in the circulation of A. phagocytophilum in municipal areas; however, hedgehogs present the greatest anaplasmosis risk for humans. Common blackbirds and squirrels carry different A. phagocytophilum variants some of which are responsible for HGA.

Sex and age differences in the diet of the Eurasian Sparrowhawk (Accipiter nisus) using web‐sourced photographs: exploring the feasibility of a new citizen science approach

Diet differences between the sexes and ages have often been recorded for bird species. Many raptor species show extreme sexual size dimorphism, with females often considerably larger than the males and these differences may be reflected in their diets. Diet studies in raptors most frequently focus on analysing prey remains or pellets collected at nest‐sites. These methods are subsequently limited to breeding birds in the breeding season and are also restricted by their inability to distinguish prey items between the sexes. The use of web‐sourced photographs to examine raptor diet has the potential to overcome some limitations of more traditional methods used to assess diet. We used this approach for the Eurasian Sparrowhawk Accipiter nisus in the United Kingdom, exploring diet between the sexes and ages throughout the entire year. In total, we obtained 843 web‐sourced photographs of Sparrowhawks with their prey items. There were 12 key prey items that had a frequency ≥ 10 in the Sparrowhawk diet: Common Wood Pigeon Columba palumbus, Common Starling Sturnus vulgaris, Eurasian Collared Dove Streptopelia decaocto, Rock Dove Columba livia, Common Blackbird Turdus merula, House Sparrow Passer domesticus, unidentified ‘small’ and ‘medium’ birds, European Goldfinch Carduelis carduelis, European Greenfinch Chloris chloris, Eurasian Blue Tit Cyanistes caeruleus and Stock Dove Columba oenas. Several prey species were more often seen in the diet of one sex or age group. Overall, average prey weights of adult females were two and a half times heavier than for adult males and one and a half times heavier for juvenile females. However, this method may be slightly biased towards larger prey items, which should be considered in future studies. Despite this limitation, our method enabled dietary differences between the sexes and ages of this highly sexual size dimorphic raptor species to be explored throughout the year.

Urbanization shapes bird communities and nest survival, but not their food quantity

As urbanization accelerates, there is an increasing focus on understanding the ecological aspects of urbanization (both direct and indirect impacts on communities and biodiversity), monitoring qualitative and quantitative changes in the fauna of urbanized areas, and examining the underlying causes of these changes. To explore the effect of urban areas on avian communities, we examined differences in species richness and abundance of birds, and survival probabilities of artificial shrub nests along an urbanization gradient (rural – suburban - urban) in a medium-sized city in Hungary. Additionally, potential food sources (arthropods captured by sticky traps) and consumption rates by insectivorous birds (predation on dummy caterpillars) were compared along the gradient. Based on our observations, the diversity of species that form bird communities did not change significantly along the gradient. However, significantly more individuals were observed in urban areas than in suburban or rural ones, primarily due to the dominance of synanthropic species: the Domestic (Columba livia f. domestica) and Wood Pigeon (Columba palumbus), House Sparrow (Passer domesticus) and European Blackbird (Turdus merula). The daily survival rates of shrub nests were significantly higher in urban and suburban areas than in rural ones. Even so, we did not find any correlations between the species richness of shrub-nesters and urbanization, whilst, they were present with higher abundance in urban than rural habitats. Although the abundance of arthropods as potential food source was not related to the degree of urbanization, the caterpillar predation by birds was significantly higher in suburban than in urban areas. Nevertheless, there were no significant differences in richness of insectivores across urbanization gradients, but their abundance was significantly higher in urban and suburban habitats than in rural ones. In conclusion, no consistent negative or positive urbanization effect could be detected in the present study, but high-level urbanization seems to increase bird abundance. Our results also suggest that shrub-nesting in urban habitats may be safer, probably due to lower predation pressure and/or favourable nesting sites for shrub nesters in cities. Nevertheless, the food availability per se seemed to be not a key driver in habitat selection of birds along the studied urbanization gradient.

Vineyards, but not cities, are associated with lower presence of a generalist bird, the Common Blackbird (Turdus merula), in Western France

BackgroundLand-use change is one of the main drivers of the global erosion of biodiversity. In that context, it is crucial to understand how landscape characteristics drive the presence of rare endangered species. Nevertheless, it is also important to study common species in multiple habitats, because they represent a large proportion of biodiversity and are essential to maintain ecological functions. Interestingly, some habitats, as farmlands with permanent crops (e.g. vineyards), have been overlooked in the literature.MethodsIn this study, we investigated the distribution of a widespread and common bird species, the Common Blackbird (Turdus merula), within and between the three main habitats of our study area (rural Western France). We specifically focused on (1) woodlands, (2) farmlands with a high vineyard coverage, and (3) moderately urbanized areas. Specifically, we aimed to assess the beneficial and detrimental effects of these habitats and their fine-scale composition on the presence of a common bird species, relying on a survey by point counts (nearly 100 locations). We studied the effects of habitats and gradients of fine-scale habitat composition on blackbird presence using logistic regression analyses.ResultsBlackbirds were present in all studied habitats. However, their presence varied between habitats, being lower in vineyards than in woodlands and cities. In woodlands and cities, fine-scale analyses did not reveal any component driving the species’ presence. However, we found that shrub and tree vegetation cover had a significant positive effect on blackbird presence in vineyards.ConclusionsOur results are in agreement with the definition of a generalist species. Interestingly, species distribution varied between habitats. The high presence of blackbirds in urban areas suggests that medium-sized cities, despite their artificialization, do not constrain the settlement of this former forest specialist and that green spaces may allow blackbirds to thrive in medium-sized cities. On the contrary, we found an impoverished presence of blackbirds in vineyards and a positive effect of vegetation on their presence in these landscapes. This suggests that permanent crops, and more generally farmlands, may impose important constraints to common species. Future studies should examine how to enhance biodiversity through agricultural management policies, especially in vineyards.

Light and territoriality : A preliminary report on a capture-recapture study of common Blackbird (Turdus Merula)

The natural light conditions and the artificial lighting of the habitats affect the quality of bird territories and the territorial behaviour of birds. However, we know almost nothing about the evolutionary consequences of light on birds. In the biomonitoring part of the project entitled “ Development of international research environment for light pollution studies”, which is carried on in Bárdudvarnok in Somogy county, Hungary, we study the apparent survival probability, adaptive morphological characteristics and area fidelity in Common Blackbird populations living in territories under different light conditions. In this preliminary report, we also describe the methods of our studies - individual marking of birds, capture and recapture, measurement of body weight, wing length and other ecomorphological parameters - and the types of data collected. Based on the outcomes of the data collection planned to continue for several years, we can formulate proposals for the design and application of artificial lighting resulting in the reduction of the adverse effects of light pollution.

Зв’язки чужорідних видів птахів з адвентивними рослинами насаджень парків і ботанічних садів

Introduction. In urban conditions, alien species of biota have become an integral part of the cultural landscape. Today, an overall assessment of the influence of alien species on the functioning of ecosystems of their secondary range as is relevant. Such an assessment requires knowledge of the connections formed by alien species in the secondary habitat. The purpose of the study was to find the connections of alien bird species with alien plant species in the parks and botanical gardens of Kyiv. Methods. Assessment was carried out in 10 forest parks, 3 botanical gardens, and 14 urban parks. In parks and botanical gardens, there is a wide range of plants alien to Kyiv Region, in contrast to forest parks. The number and distribution of birds were determined using the method of transect counts. The total area under study was about 370 hectares. Principal Component Analysis of the characteristics of habitats on which the number of alien birds may depend has been carried out. In the research, α-diversity indices of bird communities; number of people (individuals/km); number of pets (individuals/km); park’s area (ha); part of the territory; under the trees (%); part of alien species on plants communities (%) were analyzed. Results. Parus major, Turdus merula, Erithacus rubecula, Fringilla сoelebs dominate in all communities. Columba palumbus, Ficedula albicollis, Turdus pilaris, Columba livia, Apus apus, Sturnus vulgaris, Passer domesticus sometimes dominate in bird communities in parks and botanical gardens. There are no alien species in forest parks. 4 alien species nest in parks and botanical gardens: Streptopelia decaocto, Dendrocopos syriacus, Phoenicurus ochruros, Serinus serinus (from the last century). Phylloscopus trochiloides was observed for the first time. Nesting of Ph. trochiloides was not confirmed. Alien birds are not evenly distributed (0–3 species). Nest density is low: S. decaocto 0.013±0.01–0.021±0.01, D. syriacus 0.031±0.01–0.043±0.04, Ph. ochruros 0–0.034±0.02, S. serinus 0.013±0.01–0.017±0.01. We assume that alien bird species is an element that replaces the species that were eliminated from the community. Their nesting in forest parks is an indicator of a disruption of the functioning of the forest ecosystem as a result of anthropogenic transformation of the forest. The presence of alien species of birds in modern parks and botanical gardens is normal. Their biotopes were created on the sites of destroyed landscapes and with using alien plant species. Conclusion. In parks and botanical gardens, a specific structure of the plant community has developed due to the introduction of alien plant species, with a tree height of 3–5 m. As a consequence, alien birds find nesting stations in communities of nesting birds, which were not occupied by native species due to the absence of many species of tree canopy nesters and ground nesters birds. Alien species of birds also get access to vacant food resources. Alien birds use vacant resources. It was found that the area of parks has the most profound positive impact on the number of species of alien birds (+0.517), as well as the ratio of alien birds (+0.227). Other important correlations observed were the following: the number of species of alien birds in the bird communities – a part of alien species in plant communities (+0.084), the ratio of alien birds – part of alien species in plant communities (+0.041). The strongest negative connection is as follows: the number of species of alien birds in the bird communities – the number of pets (-0.213), the ratio of alien birds – the number of pets (-0.384).