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Understanding habitat selection patterns in congeneric species has raised special interest due to its importance when designing conservation strategies for the species. We analysed reproductive habitat selection of three coexisting warbler species in the eastern Iberian Peninsula. We detected the individuals by their vocalizations at 40 listening points in two study areas (Carcaixent and Alcoy). We used satellite images to identify different vegetation types and their availability. Reproductive habitat selection was analysed by the Ivlev selectivity index and a compositional analysis. In addition, we determined the effect of different habitat variables (dominant vegetation, vegetation height, cover and site) on the presence of the species fitting a binomial GLM with logistic linking function. We found that the Sardinian Warbler (Curruca Melanocephala) selected scrub-dominated areas; while the Dartford Warbler (C. undata) preferred areas with low (<50%) vegetation cover; and the Subalpine Warbler (C. cantillans) was present in areas with scrubs and low (<50%) vegetation cover, avoiding crops. The compositional analysis showed that the species used different vegetation types, in relation to their availability and that the selection differed between species. The Sardinian Warbler was the only species which showed spatial variation in reproductive habitat selection. Our results evidence that the studied warbler species select and avoid different types of vegetation in relation to their specific requirements and the present habitat structure. This represents valuable information to understand the composition of local communities and the reproductive habitat selection of the studied species. [ABSTRACT FROM AUTHOR]

For a long time, it was considered that entomogamy was the only pollination mechanism in the Mediterranean area. However, data recorded in this review prove that ornithogamy and saurogamy also take place. With the exception of the nectarivorous Cinnyris osea (Nectariniidae) which pollinates the mistletoe Picosepalus acaciae in Israel, all birds responsible for the pollination of several plant species in this area are primarily insectivorous, sedentary, or migrating passerine birds, particularly Sylvia atricapilla, S. melanocephala, Phylloscopus collibita and Parus caeruleus. They contribute, together with insects, to the pollination of Anagyris foetida, three species of Scrophularia with big flowers, Rhamnus alaternus, Brassica oleracea, and some other plants. The lacertid lizard Podarcis lilfordi acts as a pollinating agent on several W Mediterranean islands, where it effectively pollinates Euphorbia dendroides, Cneorum tricocum, and presumably Rosmarinus officinalis and Chrithmum maritimum. The flowers of some other plant species are visited by birds or by Podarcis species in the Mediterranean area, where they could also contribute to their pollination. [ABSTRACT FROM AUTHOR]

This study aimed to monitor the demographic changes of some closely related species based on bird ringing data from the CES (Constant Effort Sites) program in Hungary between 2007 and 2018, and to explore the reasons for these demographic changes. The CES program tracks breeding bird populations with standard methods. The studied species breeding in Hungary were from genera Sylvia, Curruca, and Phylloscopus. Among these species, the trends of some forest birds, like Eurasian Blackcap (Sylvia atricapilla), Lesser Whitethroat (Curruca curruca), Common Chiffchaff (Phylloscopus collybita) and Willow Warbler (Ph. trochilus) showed no substantial changes, and one of the open-habitat species, the Barred Warbler (Curruca nisoria) – a long distant migrant – showed decreasing trends. The Garden Warbler (Sylvia borin) – a trans-Saharan migrant but forest dweller – also experienced population declines. Short-distance migrants maintained stable populations. Common Whitethroat productivity displayed an increasing trend to compensate for population decline. Upon examining the Eurasian Blackcap, this study detected a strong relationship between the number of adult birds, productivity, and the number of adults captured the following year. [ABSTRACT FROM AUTHOR]

Leucocytozoon parasites remain poorly investigated in comparison to other haemosporidians. The host cell inhabited by their blood stages (gametocytes) remains insufficiently known. This study aimed to determine the blood cells inhabited by Leucocytozoon gametocytes in different species of Passeriformes and to test if this feature has a phylogenetic importance. We microscopically analyzed blood films stained with Giemsa from six different bird species and individuals and used PCR-based methods for parasite lineage identification. The DNA sequences obtained were applied for phylogenetic analysis. Leucocytozoon parasite from the song thrush Turdus philomelos (cytochrome b lineage STUR1), the blackbird Turdus merula (undetermined lineage), the garden warbler Sylvia borin (unknown lineage) inhabited erythrocytes, a parasite from the blue tit Cyanistes caeruleus (PARUS4) infects lymphocytes, while in the wood warbler Phylloscopus sibilatrix (WW6) and the common chiffchaff Phylloscopus collybita (AFR205) they were found inhabiting thrombocytes. Parasites infecting thrombocytes were closely related, while the parasites infecting erythrocytes were placed in three different clades, and the one found in lymphocytes was placed in a separate clade. This shows that the determination of host cells inhabited by Leucocytozoon parasites can be phylogenetically important and should be considered in future species descriptions. Noteworthy, phylogenetic analysis might be used for the prediction of which host cells parasite lineages might inhabit. [ABSTRACT FROM AUTHOR]

In migratory birds, constraints due to breeding are relaxed during the non-breeding season and thus, social behaviours and spatial associations are potentially more directly coupled to food resources and habitats. Use of space and territorial behaviour has rarely been studied in Afro-Palearctic migrants. Variation in strategies could exist among species within the same habitat because of differences in foraging, diet and microhabitat. We compare use of space and association with conspecifics in Common Chiffchaffs Phylloscopus collybita and Subalpine Warblers Sylvia cantillans at a non-breeding site in northern Senegal using radio telemetry and playback experiments. Home ranges of Chiffchaffs were larger and overlapped more than those of Subalpine Warblers. Though Chiffchaffs were often close together, we found no signs of spatial association among individuals in either species. Chiffchaffs showed no clear pattern of territorial response to conspecific song; whereas, playback elicited a territorial response in most Subalpine Warblers. Our results suggest species-specific differences in use of space that might reflect differences in foraging ecology and microhabitat. [ABSTRACT FROM AUTHOR]

The complete mitogenome of the Lesser Whitethroat, Sylvia curruca blythi Ticehurst & Whistler, 1933 was determined, which belongs to Sylviidae, Passeriformes. The mitogenome had a length of 17,959 bp and consisted of 37 genes including 13 PCGs, 2 ribosomal RNAs (rRNA) genes, and 22 transfer RNAs (tRNA) genes. In addition, two control regions (CRs) were also existed in the mitogenome, with Sylvioidea typcial gene arrangement of cytb-trnT-CR1-trnP-nad6-trnE-CR2-trnF-rrnS. Phylogenetic analysis using 37 mitochondrial genes of 17 related species revealed that S. c. blythi had a closer relationship with S. crassirostris, and the monophyly of Sylvia was also recovered. The mitogenome data of S. c. blythi would provide useful resources for further studying the evolution of Sylvia and the subspecies taxonomic revision of S. curruca intraspecific.

Summary: Electrical cable trays are used in large quantities in nuclear power plants (NPPs) and are one of the main potential sources of fire. A malfunction of electrical equipment due to thermal stress for instance may lead to the loss of important safety functions of the NPPs. The investigation of such fires in a confined and mechanically ventilated enclosure has been scarce up to now and limited to nuclear industry. In the scope of the OECD PRISME‐2 project, the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) conducted more than a dozen fire tests involving horizontal electrical cable trays burning either in open atmosphere or inside mechanically ventilated compartments to investigate this topic. A semi‐empirical model of horizontal cable tray fires in a well‐confined and mechanically ventilated enclosure was developed. This model is partly based on the approach used in FLASH‐CAT and on experimental findings from IRSN cables fire tests. It was implemented in the two‐zone model SYLVIA. The major features of the compartment fire experiments could then be reproduced with acceptable error, except for combustion of unburned gases. The development of such a semi‐empirical model is a common practice in fire safety engineering concerned with complex solid fuels. [ABSTRACT FROM AUTHOR]

Small area ecological studies are commonly used in epidemiology to assess the impact of area level risk factors on health outcomes when data are only available in an aggregated form. However, the resulting estimates are often biased due to unmeasured confounders, which typically are not available from the standard administrative registries used for these studies. Extra information on confounders can be provided through external data sets such as surveys or cohorts, where the data are available at the individual level rather than at the area level; however, such data typically lack the geographical coverage of administrative registries. We develop a framework of analysis which combines ecological and individual level data from different sources to provide an adjusted estimate of area level risk factors which is less biased. Our method (i) summarizes all available individual level confounders into an area level scalar variable, which we call ecological propensity score (EPS), (ii) implements a hierarchical structured approach to impute the values of EPS whenever they are missing, and (iii) includes the estimated and imputed EPS into the ecological regression linking the risk factors to the health outcome. Through a simulation study, we show that integrating individual level data into small area analyses via EPS is a promising method to reduce the bias intrinsic in ecological studies due to unmeasured confounders; we also apply the method to a real case study to evaluate the effect of air pollution on coronary heart disease hospital admissions in Greater London. [ABSTRACT FROM AUTHOR]

As Bronwyn Polaschek mentions in The Postfeminist Biopic, the film Sylvia (Christine Jeffs, 2003) is based on biographies of Sylvia Plath that focus on her relationship with husband Ted Hughes—such as Janet Malcolm’s The Silent Woman. In this paper, grounded in the works of Linda Hutcheon, Mary E. Hawkesworth, and Tracy Brain, I argue that this biography works as a palimpsest of Sylvia and that the film constructs Plath as the Ariel persona, neglecting her “Juvenilia”—her early poetry, as it has been defined by Hughes. Sylvia actually leaves Plath’s early life—before she met Hughes—aside and it thus ends up portraying her more as a wife than as a writer. Finally, by bringing information on Plath’s life before she met Hughes from a more recent biography (by Andrew Wilson), I analyze how a different image of Plath might have been created if this part of her life were not missing in the film.

The evolution of migration in birds and its causes are still subject of debate. Recent studies tracking current bird migration have identified peaks in net primary productivity (NPP) as a main driver of bird migratory behaviour. However, it is unclear which variables may have played a major role in the evolution of bird migration at deeper phylogenetic levels. Here, we used phylogenetic comparative methods to assess whether the evolutionary patterns of migratory distances, as a proxy for migratory behaviour, are correlated with several biometric, climatic and productivity variables in a phylogenetic context, using Sylvia warblers as a case study. Our results recover NPP in the breeding range and during the breeding season as the variable with stronger positive correlation with migratory distances, being always included in the best models considering all potential variables. Several climatic variables show a correlation with the evolution of migration, but those are also tightly correlated with NPP. Among morphological variables, migratory lineages tend to have longer wings than sedentary ones. Although NPP has been identified as a driver of migratory behaviour in current species, in a phylogenetic scale it is not possible to disentangle if it was a main driver in the evolution of bird migratory behaviour or a consequence of it, yet migration and NPP seem to be tightly related today and along the long evolutionary history of these passerines. The evolution of migration in birds and its causes are still subject to debate. It is unclear which variables may have played a major role in the evolution of bird migration at deeper phylogenetic levels. Here, we used phylogenetic comparative methods to assess whether the evolutionary patterns of migratory distances, as a proxy for migratory behaviour, are correlated with several biometric, climatic and productivity variables in a phylogenetic context, using Sylvia warblers as a case study. Our results recover Net Primary Productivity (NPP) in the breeding range and during the breeding season as the variable with stronger positive correlation with migratory distances. Migration and NPP seem to be tightly related today and along the long evolutionary history of these passerines. [ABSTRACT FROM AUTHOR]

By means of DNA barcoding and microsatellite analyses, we studied the species and individuals of legitimate seed dispersers of the Mediterranean shrub Pistacia lentiscus, a keystone species that represents the main source of food in winter for frugivorous birds. We collected dropping of birds containing seeds, and after DNA extraction we amplified and sequenced a fragment of the mitochondrial COI gene. Through BLASTN queries of the sequenced fragments against registered sequences in the GenBank database we identified the bird species that are currently dispersing P. lentiscus seeds. Further, through the amplification of specific nuclear microsatellite loci we calculated standard genetic diversity parameters of the population of birds from the genus Sylvia (the blackcap and Sardinian warbler), the most important dispersers of P. lentiscus. Five bird species were identified as seed dispersers through their barcode match. Further, we found that S. melanocephala displayed slightly lower levels of genetic diversity than S. atricapilla. In this study we show how the genetic analyses of environmental faecal samples can be a useful and convenient tool for the study of plant-frugivore interactions through the ascertainment of the identity of the species involved and through the analyses of genetic variability of their populations. [ABSTRACT FROM AUTHOR]

The water spray systems are widely used for fire safety area and is a well-established technique for providing safety and protection of nuclear installations and also industrial facilities. One major challenge is to be able to properly determine the technical features of the water spray system that are required for predictive simulations. For that, a Phase Doppler Interferometer (PDI) device, that is a complex and challenging laser technique, is often used to measure the water droplets size distributions and the water droplets velocities. However, some usual water spray models can require as input parameters only an overall water droplets size distribution and water droplets initial velocity and some statistical methods are needed to determine them from local accurate measurements. In this paper, it is addressed a new calibration approach for assessing the input parameters of this modeling by using large-scale and well-controlled fire tests. Then, by introducing some correlations to take into account different operating conditions of the pressure at the spray nozzle head, this technique is validated on other large-scale fire tests. After discussing thoroughly the results, this new method shows that it can be a valuable and efficient tool for determining the overall features of water spray systems linked with the modeling of water spray system used in this study. [ABSTRACT FROM AUTHOR]

Aim The ecological niche of a species is dynamic at a variety of spatial and temporal scales; embracing this complexity is required for accurate assessment of species' niche requirements and to forecast how species will respond to novel and dynamic climates. In the context of recent advances in species distribution modelling, however, both the environment and the ecological niche of a species have often been treated and quantified as static entities. Here, our aim was to explore how species' realized niches and geographical ranges are dynamically shaped by the decoupled spatio-temporal availability of different environmental conditions, using the migration of Sylvia warblers as an example. Location Palaearctic, Afrotropical and Indo-Malay ecozones. Methods We used a species distribution modelling approach to evaluate the niche characteristics of Sylvia warblers under their actual migration strategies as well as null models assuming resident behaviour. We focused on climate and land cover as niche dimensions, taking into account the spatial availability of environmental conditions during the peak breeding and non-breeding season for each Sylvia species. Results Migration did not increase the overlap between breeding and non-breeding niches compared with breeding and non-breeding niche overlap in resident null models. Sylvia warblers did not compensate for the costs of a longer migratory journey by tracking their climatic niche or land-cover niche more closely. Instead, Sylvia warblers migrated further than the closest available area with suitable climate and land cover. Main conclusions Climatic niche tracking is unlikely to be the main driver of migration in Sylvia warblers. We suggest that taking dynamic environments into account and comparing actual niche characteristics to those resulting from alternative possible range dynamics enhances our understanding of the drivers behind organisms' movements and distributions. [ABSTRACT FROM AUTHOR]

Aim As global temperatures have increased, many species distributions have exhibited polewards shifts, a trend that is predicted to continue in future decades. However, the mechanisms underlying such shifts are not well understood. Here we quantify the impact of large-scale variation in temperature on reproductive output within a group of migratory birds to assess the potential for future range changes. Location Western Europe. Methods We use data from captures of 350,000 individual birds, collected under constant effort ringing protocols from 1994-2006, to estimate productivity (percentage of juveniles caught) for seven species of migrant warblers (family Sylviidae) breeding in Europe in relation to spring temperature and latitude by fitting generalized linear mixed models. Results Productivity was highest at mid-latitudes for six of our seven study species and did not change significantly over the study period. Only one species (reed warbler, Acrocephalus scirpaceus) showed increased productivity at northern sites as expected. Six of the seven species also showed evidence for local adaptation, with productivity decreasing as temperatures diverged from the local mean. However, for three of these species the 'optimum' temperature was greater than the local mean temperature at the majority of sites. Main conclusions These results indicate that latitudinal gradients in productivity are likely to influence large-scale abundance patterns, but that adaptation to local climate conditions has the potential to constrain the rate of northward range shifts in many species. [ABSTRACT FROM AUTHOR]

The complete mitogenome of the Lesser Whitethroat, Sylvia curruca blythi Ticehurst & Whistler, 1933 was determined, which belongs to Sylviidae, Passeriformes. The mitogenome had a length of 17,959 bp and consisted of 37 genes including 13 PCGs, 2 ribosomal RNAs (rRNA) genes, and 22 transfer RNAs (tRNA) genes. In addition, two control regions (CRs) were also existed in the mitogenome, with Sylvioidea typcial gene arrangement of cytb-trnT-CR1-trnP-nad6-trnE-CR2-trnF-rrnS. Phylogenetic analysis using 37 mitochondrial genes of 17 related species revealed that S. c. blythi had a closer relationship with S. crassirostris, and the monophyly of Sylvia was also recovered. The mitogenome data of S. c. blythi would provide useful resources for further studying the evolution of Sylvia and the subspecies taxonomic revision of S. curruca intraspecific. [ABSTRACT FROM AUTHOR]

Background and Aims It has traditionally been considered that the flowers of Scrophularia are mainly pollinated by wasps. We studied the pollination system of four species which stand out for their large and showy flowers: S. sambucifolia and S. grandiflora (endemics of the western Mediterranean region), S. trifoliata (an endemic of the Tyrrhenian islands) and S. calliantha (an endemic of the Canary Islands). Our principal aim was to test whether these species were pollinated by birds or showed a mixed pollination system between insects and birds. Methods Censuses and captures of insects and birds were performed to obtain pollen load transported and deposited on the stigmas. Also, a qualitative and quantitative analysis of the flowers and inflorescences was carried out. Key Results Flowers were visited by Hymenoptera and by passerine birds. The Canarian species was the most visited by birds, especially by Phylloscopus canariensis, and its flowers were also accessed by juveniles of the lizard Gallotia stehlini. The most important birds in the other three species were Sylvia melanocephala and S. atricapilla. The most important insect-functional groups in the mixed pollination system were: honey-bees and wasps in S. sambucifolia; bumble-bees and wasps in S. grandiflora; wasps in S. trifoliata; and a small bee in S. calliantha. Conclusions The species studied show a mixed pollination system between insects and passerine birds. In S. calliantha there is, in addition, a third agent (juveniles of Gallotia stehlini). The participation of birds in this mixed pollination system presents varying degrees of importance because, while in S. calliantha they are the main pollinators, in the other species they interact to complement the insects which are the main pollinators. A review of different florae showed that the large showy floral morphotypes of Scrophularia are concentrated in the western and central Mediterranean region, Macaronesia and USA (New Mexico). [ABSTRACT FROM AUTHOR]

Nectar exploitation by European birds mainly refers to passerines feeding on exotic plants, although some recent studies described nectar-feeding by trans-Saharan passerines on local plants. We examined which birds and plants are involved in nectar consumption and investigated the consequences of nectar use on plasma blood glucose concentrations during spring migration at a stopover site in the central Mediterranean. We recorded 12 opportunistic nectar-feeding species, with Sylvia warblers in particular showing a marked nectarivory, and 6 plants used by birds, no one of which shows typical 'bird flowers' features. Moreover, we demonstrated that nectar uptake led to an increase in plasma glucose concentrations and that nectar was drunk not only by birds in poor physical condition. The nectar consumption is fully in accordance with time-minimising migration models, allowing birds to obtain water and energy at stopover sites in a short time: nectar is easy to find and quick to digest. [ABSTRACT FROM AUTHOR]

The article explores the role of migrating warblers in pollination. Warblers are known nectarivores and in their every stop to sip nectars, pollen grains are attached to their bodies. The warblers at Ventotene Island of Italy was used to observe their stop-over behaviors during spring migration and the flowering plants F. communis (Apiaceae) and Brassica sp. (Brassicaceae) was observed for its seasonal flowering patterns. Garden Warbler S. borin and Common Whitethroat S. communis were found to carry the pollen of F. communis while Eurasian Blackcap Sylvia atricapilla and Subalpine Warbler S. cantillans land with Brassica sp. pollens.

The article focuses on a study which examined nectar use by songbirds at stopover sites in the Mediterranean region. Nectar-feeding by birds was assessed on sites in 3 countries, namely, Spain, Italy and Greece. Among the bird species considered in the study were the blackcap, garden warbler S. borin, subalpine warbler S. cantillans and whitethroat S. communis. It was noted that the highest proportion of birds with fresh pollen on their plumage were observed in Ventotine and Anthikitira. Sylvia warblers demonstrated the highest proportions with fresh pollen on the plumage in both sites.

The timing of when migrant birds return to breed is a key component of studies of the impact of climate change upon bird populations. However, such data are not distributed evenly across the World, and in the Northern Hemisphere are underrepresented in Asia and the east of Europe. Therefore, to help rectify this bias, we analysed first arrival dates (FAD) of four species of Sylvia warblers (Blackcap Sylvia atricapilla, Whitethroat S.communis, Lesser Whitethroat S.curruca and Garden Warbler S.borin) collected in the Tatarstan Republic of Russia between 1957 and 2008. Over the whole period the species returned to their breeding sites between three and six days earlier; these trends were significant except for Whitethroat. Advances in arrival were especially apparent in the two earlier species, Blackcap and Lesser Whitethroat, mainly because local temperatures for March had risen substantially. Except for Whitethroat, FADs were significantly related to temperatures in the African wintering ground and/or in Tatarstan. Whilst significant correlations occurred between FADs of some of the species, there was considerable variability in these relationships indicating a species-specific response to rising temperatures. Changes in FADs in this eastern extremity of Europe were smaller than in Central and Western Europe. [ABSTRACT FROM AUTHOR]

For computational de novo design, a general retrospective validation work is a very challenging task. Here we propose a comprehensive workflow to de novo design driven by the needs of computational and medicinal chemists and, at the same time, we propose a general validation scheme for this technique. The study was conducted combining a suite of already published programs developed within the framework of the NovoBench project, which involved three different pharmaceutical companies and four groups of developers. Based on 188 PDB protein–ligand complexes with diverse functions, the study involved the ligand reconstruction by means of a fragment-based de-novo design approach. The structure-based de novo search engine FlexNovo showed in five out of eight total cases the ability to reconstruct native ligands and to rank them in four cases out of five within the first five candidates. The generated structures were ranked according to their synthetic accessibilities evaluated by the program SYLVIA. This investigation showed that the final candidate molecules have about the same synthetic complexity as the respective reference ligands. Furthermore, the plausibility of being true actives was assessed through literature searches. [ABSTRACT FROM AUTHOR]

The article presents a study which assesses the species and generic relationship of Horizorhinus with the family Muscicapidae. It also classifies the generic status of Horizorhinus. For phylogenic analysis, the researches relied their assessment on the mitochondrial ND2 gene. They found the placement of Horizorhinus within babblers, and as part of the genus Sylvia abyssinica. The authors suggest, based on their molecular finding that Horizorhinus be subsumed into genus Sylvia, and Dohrn's Thrush-babbler now be recognized as Sylvia dohrni.

Aim  To explore the potential impacts of climatic change on species with different migratory strategies using Sylvia warblers breeding in Europe as a ‘model’ species group. Location  Europe and Africa. Methods  Climate response surfaces and generalized additive models (GAMs) were used to model relationships between species recorded breeding and non-breeding ranges and recent climate. Species potential future breeding and non-breeding ranges were simulated for three scenarios of late 21st-century climate. The simulated potential future and present ranges were compared in terms of their relative extent and overlap, as well as their location. The impact of any shifts in potential range location on migration distance were quantified. Results  Potential breeding ranges consistently showed a shift northwards, whereas potential non-breeding ranges showed no consistent directional shift, even when trans-Saharan migrants were considered separately from resident/short-distance or partial migrants. Future potential range extent relative to simulated recent range extent varied considerably among species, although on average range extent increased. Overlap between future and recent simulated range was generally low, averaging < 36% for both breeding and non-breeding ranges. Overlap was consistently less for range-restricted than for widespread species. Migration distance increased generally, by about twice as much in the case of trans-Saharan migrant species than for short-distance migrants. In many cases potential future non-breeding areas were simulated in regions far from the species present non-breeding area, suggesting that new migration strategies and routes may need to be developed in response to climatic change. Main conclusions  Migratory species can be expected to suffer greater negative impacts from climatic change than species that are resident or undertake only short-distance or partial migrations. Trans-Saharan migrants face the greatest potential increases in migration distances, whereas range-restricted species are expected to experience major population reductions because of the limited, or in some cases lack of, overlap between their present and potential future ranges. [ABSTRACT FROM AUTHOR]

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Copyright of Journal fuer Ornithologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

AimsTo investigate the effect of climate on the timing of spring arrival of many species at their northern limit of breeding distribution and to seek evidence of any long-term trend. MethodsObservations of spring arrivals of 71 species into Troms, north Norway (69–70°N) between 1970 and 2000 by members of the local branch of the Norwegian Ornithological Society were analysed and related to available weather parameters. ResultsThe first migrants arrive in mid-March when air temperatures are still below 0°C andc. 1 m of snow is on the ground, with the main influx in late April and throughout May. By then much of the snow has melted and temperatures arec. 5°C. There was no evidence of a long-term trend in the median dates of arrival across 31 species in Troms between 1980 and 2000. However among 14 species for which detailed data exist in a limited area around Tromsø, the Golden PloverPluvialis apricariashowed a significant trend towards an earlier arrival and the Willow WarblerPhylloscopus trochilusshowed the opposite. Spring migration tended to be advanced during warm springs, and seven of the above subsets of 14 species showed significant negative correlations between their arrival dates and temperature. One showed a positive correlation. ConclusionThe data collected to date are a good baseline for future studies of the effects of climate change on migration phenology. [ABSTRACT FROM PUBLISHER]

The effects of post-fire changes in vegetation and habitat quality on the developmental stability of individual birds have not been assessed to date. Here we compare fluctuating asymmetry in tail feathers of Sardinian WarblersSylvia melanocephalainhabiting two shrubby zones, the first burned in both 1982 and 1994 and the second only in 1982. Juveniles with unmoulted rectrices showed significantly higher levels of tail feather asymmetry in the zone burned in 1994. This result is consistent with the hypothesis that recently burned shrublands offer lower quality habitats for this species. Because feather asymmetry was positively and significantly related to the abundance of low shrubs up to 50 cm tall, we suggest that juvenile assessment of habitat quality is primarily based on the structure of the shrub layer. [ABSTRACT FROM PUBLISHER]

Field boundary characteristics influencing territory establishment and nesting success of Whitethroats and Yellowhammers on farmland in Leicestershire were investigated. Hedge height had a negative influence on the presence of breeding Whitethroats. The abundance of herbaceous vegetation in field boundaries had a positive influence on both species. The relationship was strongest for Whitethroats which nested almost exclusively in herbaceous vegetation. Nesting success of Whitethroats was higher than that of Yellowhammers. Yellowhammer nests in hedges were more susceptible to predation than those in herbaceous vegetation. Maintaining low hedges and establishing uncut 2-m strips of perennial herbaceous vegetation in field boundaries would contribute to the conservation of Whitethroats and Yellowhammers on farmland. [ABSTRACT FROM PUBLISHER]

Many European countries have annual breeding bird monitoring schemes based on nationwide samples; most are in northern and western Europe. We have developed a method to produce yearly population indices of bird species across countries by combining the results of existing national schemes. The method takes into account the differences in population sizes per country, as well as the differences in field methods, and the numbers of sites and years covered by the national schemes. In order to test the method, we collected raw data from a number of countries and applied an index method to produce scheme results per country. Data were collected for five farmland species (LapwingVanellus vanellus, LinnetCarduelis cannabina, SkylarkAlauda arvensis, WhitethroatSylvia communisand YellowhammerEmberiza citrinella), from seven countries (UK, Netherlands, Denmark, Germany, Finland, Latvia and Estonia) for a 20-year period (1978–97). The trial demonstrated that it was possible to combine national indices to provide supra-national yearly totals and their standard errors; the results were similar to those produced when the raw data were used. Thus, yearly European indices can be produced by exchanging only limited amounts of information, that is the national yearly indices of each species or, preferably, the yearly population numbers and their standard errors. At a European scale, the populations of the five species selected have changed considerably. In western Europe (UK, Netherlands, Denmark and former West Germany combined), Linnet, Skylark and Yellowhammer have declined and Whitethroat has increased. Most changes occurred during the first ten-year period (1978–88). The changes in eastern Europe (the remaining countries) were less clear, in part because the statistical power of the national schemes is as yet limited. [ABSTRACT FROM PUBLISHER]

Blackcaps ( Sylvia atricapilla) that breed in central Europe have usually migrated to Mediterranean or African wintering grounds. In the past several decades, a portion of this breeding population has started migrating to the British Isles to overwinter and this population has increased dramatically. Several factors, including higher annual survivorship (due to supplemental feeding and reduced migratiry distance), assortative mating, and enhanced reproductive success may be involved in this rapid population growth. As part of an intensive, long-term study of this population, we tested the hypothesis that the differences in photoperiod experienced by British-wintering versus Mediterranean-wintering blackcaps might lead to relatively early vernal (i.e., migratory and/or reproductive) physiological condition in members of the former group. We found that birds exposed to photoperiodic conditions that simulated migration to Britain to overwinter generally initiated vernal migratory activity earlier than birds held under conditions simulating migration to traditional wintering areas in central Spain. This difference, coupled with the shorter migratory distance to the British Isles, leads to significantly earlier estimated arrival dates for blackcaps that winter in Britain compared to central Spain. Bimodality in arrival times suggests that assortative mating on central European breeding grounds might occur between members of the different wintering populations. Males exposed to British-winter photoperiods showed significantly earlier testicular development than males kept under Spanish-winter photoperiods. Early arrival on the breeding grounds, coupled with accelerated reproductive condition, should lead to a relatively early reproductive effort, perhaps increasing average reproductive success. In general, these results support the hypothesis that differences in photoperiod on the wintering grounds may play an important role in the dynamic state of this population. [ABSTRACT FROM AUTHOR]