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The Eurasian skylark (Alauda arvensis) is an open-habitat passerine bird that is declining throughout Europe, mainly due to agricultural intensification. However, population responses to environmental changes are often geographic- and environment-dependent, preventing generalisation and transferability of ecological relationships. For three sub-regions of Lombardy (northern Italy) characterised by both different environmental conditions and human pressures (the Alps, Plain, Oltrepò), we decomposed population trends (1992–2021) of the species and assessed changes of the realised Grinnellian niches over three decades. In each sub-region, although the niche did not show divergence, we found an overall reduction over time. In the Alps, contraction of niche occupancy in meadows and pastures was not associated with a population decline. It is likely due to extensive availability of natural grasslands that counteracted the niche reduction and promoted a positive population trend (+164%). Conversely, in the Plain and the Oltrepò sub-regions, the observed population declines (−99% and −36%, respectively) could be linked to a general decrease of niche occupancy in arable lands. In the Oltrepò, differently from the Plain, a gradual expansion of the niche in meadows and pastures at higher altitudes could have counterbalanced the former reduction, playing a significant role to mitigate the negative population trend in the area. The joint application of population trend analysis and niche modelling, as well as the decomposition of population responses in relation to different environmental contexts, can contribute to a better understanding of ecological processes affecting population dynamics and to support policy makers for planning targeted conservation strategies.

Widespread extinction is a critical threat to biodiversity and is largely caused by human overexploitation of habitat and populations. A widely used and hence well studied organism group for indication of biodiversity is birds. In Europe especially, farmland specialists have suffered from intensified agricultural practices such as increase of monoculture, use of pesticides, and heavy machinery. This has been shown to be partly caused by an EU legislation called the Common Agricultural Policy (CAP). A specific type of farmland, termed High Nature Value (HNV) farmland, seems to be particularly advantageous for farmland specialist birds and makes up an important conservation target. The current study was done in the Natura2000 reserve Târnava Mare, Romania, to find out which habitat types play an essential role for occurrence of farmland species. Farmlands in Târnava Mare are highly diverse in structure, characterizing a mosaic of grassland, meadows and fields, and low-intensity farming practices. With bird point count survey data from 2015 to 2019, I evaluated the effect of different habitat types on five species listed in the Farmland Bird Indicator (FBI) and as farmland specialists: red-backed shrike (Lanius collurio), yellowhammer (Emberiza citrinella), Eurasian skylark (Alauda arvensis), Eurasian tree sparrow (Passer montanus), and common whitethroat (Sylvia communis). I compared habitat proportion in presence and absence of the species for 2019’s data with Mann-Whitney tests. They all showed significant results for meadow proportion. All species except the common whitethroat showed significant results for crop proportion, while only two species (red-backed shrike and yellowhammer) showed significant results for scrub. Independent of which habitat type was tested (meadow, crop or scrub), all species with significant result – except for Eurasian skylark with a negative relationship in crop habitat - showed a positive response to a higher proportion of the tested ha

Widespread extinction is a critical threat to biodiversity and is largely caused by human overexploitation of habitat and populations. A widely used and hence well studied organism group for indication of biodiversity is birds. In Europe especially, farmland specialists have suffered from intensified agricultural practices such as increase of monoculture, use of pesticides, and heavy machinery. This has been shown to be partly caused by an EU legislation called the Common Agricultural Policy (CAP). A specific type of farmland, termed High Nature Value (HNV) farmland, seems to be particularly advantageous for farmland specialist birds and makes up an important conservation target. The current study was done in the Natura2000 reserve Târnava Mare, Romania, to find out which habitat types play an essential role for occurrence of farmland species. Farmlands in Târnava Mare are highly diverse in structure, characterizing a mosaic of grassland, meadows and fields, and low-intensity farming practices. With bird point count survey data from 2015 to 2019, I evaluated the effect of different habitat types on five species listed in the Farmland Bird Indicator (FBI) and as farmland specialists: red-backed shrike (Lanius collurio), yellowhammer (Emberiza citrinella), Eurasian skylark (Alauda arvensis), Eurasian tree sparrow (Passer montanus), and common whitethroat (Sylvia communis). I compared habitat proportion in presence and absence of the species for 2019’s data with Mann-Whitney tests. They all showed significant results for meadow proportion. All species except the common whitethroat showed significant results for crop proportion, while only two species (red-backed shrike and yellowhammer) showed significant results for scrub. Independent of which habitat type was tested (meadow, crop or scrub), all species with significant result – except for Eurasian skylark with a negative relationship in crop habitat - showed a positive response to a higher proportion of the tested ha

In Deutschland wurde die Energiewende von einem auf konventionellen Energieträgern beruhenden zu einem auf erneuerbaren Energiequellen basierenden System 2002 erstmalig politisch und rechtlich beschlossen. Dem politischen Beschluss des Bundes sind auf regionaler Ebene zahlreiche Gemeinden, Kommunen und Landkreise mit eigenen politischen Willensbekundungen und Beschlüssen gefolgt, den Energieverbrauch durch erneuerbare Energiequellen zu decken. Die Umsetzung geht unter anderem mit einer flächigen Ausweitung des Anbaus von Bioenergiepflanzen einher, was zu einer kontroversen Diskussion um Nahrungsmittelsicherheit, Biodiversität und Landschaftsveränderungen geführt hat. In der vorliegenden Arbeit wird vor diesem Hintergrund eine Einschätzung der zu erwartenden Veränderungen des Vorkommens der Feldlerche (Alauda arvensis) durch einen ausgeweiteten Anbau von Bioenergiepflanzen im Landkreis Schwäbisch Hall erarbeitet. Die Feldlerche wurde aufgrund der guten Forschungslage zur Feldlerche, ihrer Gefährdung („Rote Liste der Brutvögel Deutschlands“) sowie ihrer Bedeutung als Indikatorart für offene Agrarlandschaften ausgewählt (Feldlerchen meiden vertikale Strukturen (Feldhecken, Waldränder etc.) in der Landschaft). Damit steht sie stellvertretend auch für andere Arten, die von Veränderungen offener Agrarlandschaften durch einen ausgeweiteten Anbau von Bioenergiepflanzen betroffen sind. Die Arbeit basiert auf der Entwicklung eines Generalisierten Linearen Modells anhand eines stratifizierten Vogelmonitorings von Baden-Württemberg, das zur Entwicklung eines Artenvielfaltsindikators der Agrarlandschaft in einem Forschungsprojekt des Bundesministerium für Ernährung, Landwirtschaft und Verbraucherschutz (BMELV) entwickelt wurde. Aus dem Vogelmonitoring wurden die Daten des Stratums ausgewählt, indem der Landkreis Schwäbisch Hall liegt und für die Erstellung des Habitatmodells der Feldlerche verwendet. Um zu einer Einschätzung der zu erwartenden Veränderungen der Feldlerchenbestän, For the first time in 2002, the transformation of the conventional energy system into a system based on renewable energies was politically and legally decided in Germany. On the regional level numerous communities and municipalities followed this decision by voicing their own political resolutions, addressing the coverage of energy consumption with renewable energies. Their implementation is accompanied by a spatial expansion of bioenergy crops which lead to a controversial discussion about food safety, biodiversity and landscape change. Framed by the above mentioned discussion, this study assesses potential changes of skylark (Alauda arvensis) occurrence caused by a spatial expansion of bioenergy crops in the municipality of Schwäbisch Hall, Germany. The skylark was selected due to the comprehensive state of research about skylarks, their endangerment (“Red list of German breeding birds”), and the status as umbrella species for open agricultural landscapes (skylarks typically avoid vertical structures like hedges or edges of forests). The latter emphasizes their role as representatives for other species which are potentially affected by an expansion of bioenergy crops. This study is based on a stratified bird monitoring scheme of Baden-Württemberg, which was developed during a project that aimed to set up an indicator for species richness and was financed by the Bundesministerium für Ernährung, Landwirtschaft und Verbraucherschutz (BMELV). From the bird monitoring scheme, the stratum, which covers the municipality of Schwäbisch Hall, was extracted and served as a base for the development of a Generalized Linear Habitat Model of the skylark. In order to assess potential habitat changes caused by an expansion of bioenergy crops, Schwäbisch Hall was mapped with an airborne remote sensing technology in 2011. The resulting aerial images were transformed into orthophotos and later classified (focusing on agricultural areas) with an object oriented image analysis approach

In Deutschland wurde die Energiewende von einem auf konventionellen Energieträgern beruhenden zu einem auf erneuerbaren Energiequellen basierenden System 2002 erstmalig politisch und rechtlich beschlossen. Dem politischen Beschluss des Bundes sind auf regionaler Ebene zahlreiche Gemeinden, Kommunen und Landkreise mit eigenen politischen Willensbekundungen und Beschlüssen gefolgt, den Energieverbrauch durch erneuerbare Energiequellen zu decken. Die Umsetzung geht unter anderem mit einer flächigen Ausweitung des Anbaus von Bioenergiepflanzen einher, was zu einer kontroversen Diskussion um Nahrungsmittelsicherheit, Biodiversität und Landschaftsveränderungen geführt hat. In der vorliegenden Arbeit wird vor diesem Hintergrund eine Einschätzung der zu erwartenden Veränderungen des Vorkommens der Feldlerche (Alauda arvensis) durch einen ausgeweiteten Anbau von Bioenergiepflanzen im Landkreis Schwäbisch Hall erarbeitet. Die Feldlerche wurde aufgrund der guten Forschungslage zur Feldlerche, ihrer Gefährdung („Rote Liste der Brutvögel Deutschlands“) sowie ihrer Bedeutung als Indikatorart für offene Agrarlandschaften ausgewählt (Feldlerchen meiden vertikale Strukturen (Feldhecken, Waldränder etc.) in der Landschaft). Damit steht sie stellvertretend auch für andere Arten, die von Veränderungen offener Agrarlandschaften durch einen ausgeweiteten Anbau von Bioenergiepflanzen betroffen sind. Die Arbeit basiert auf der Entwicklung eines Generalisierten Linearen Modells anhand eines stratifizierten Vogelmonitorings von Baden-Württemberg, das zur Entwicklung eines Artenvielfaltsindikators der Agrarlandschaft in einem Forschungsprojekt des Bundesministerium für Ernährung, Landwirtschaft und Verbraucherschutz (BMELV) entwickelt wurde. Aus dem Vogelmonitoring wurden die Daten des Stratums ausgewählt, indem der Landkreis Schwäbisch Hall liegt und für die Erstellung des Habitatmodells der Feldlerche verwendet. Um zu einer Einschätzung der zu erwartenden Veränderungen der Feldlerchenbestän, For the first time in 2002, the transformation of the conventional energy system into a system based on renewable energies was politically and legally decided in Germany. On the regional level numerous communities and municipalities followed this decision by voicing their own political resolutions, addressing the coverage of energy consumption with renewable energies. Their implementation is accompanied by a spatial expansion of bioenergy crops which lead to a controversial discussion about food safety, biodiversity and landscape change. Framed by the above mentioned discussion, this study assesses potential changes of skylark (Alauda arvensis) occurrence caused by a spatial expansion of bioenergy crops in the municipality of Schwäbisch Hall, Germany. The skylark was selected due to the comprehensive state of research about skylarks, their endangerment (“Red list of German breeding birds”), and the status as umbrella species for open agricultural landscapes (skylarks typically avoid vertical structures like hedges or edges of forests). The latter emphasizes their role as representatives for other species which are potentially affected by an expansion of bioenergy crops. This study is based on a stratified bird monitoring scheme of Baden-Württemberg, which was developed during a project that aimed to set up an indicator for species richness and was financed by the Bundesministerium für Ernährung, Landwirtschaft und Verbraucherschutz (BMELV). From the bird monitoring scheme, the stratum, which covers the municipality of Schwäbisch Hall, was extracted and served as a base for the development of a Generalized Linear Habitat Model of the skylark. In order to assess potential habitat changes caused by an expansion of bioenergy crops, Schwäbisch Hall was mapped with an airborne remote sensing technology in 2011. The resulting aerial images were transformed into orthophotos and later classified (focusing on agricultural areas) with an object oriented image analysis approach

Bioenergy production is seen as one way of meeting future energy needs. The growing demand for biomass for energy production induces the cultivation of a few fast growing and high-yielding energy crops on vast areas of arable land. This land-use change has been found associated with the reduction of habitat suitability for farmland birds and a decline in farmland biodiversity in general. A large number of studies have assessed the ecological effects of energy crop cultivation at the local scale of a single field. This study focuses on regional landscape changes caused by increased energy crop cultivation, which includes reduction of crop-type richness and spatial concentration of single crop-types. We present a spatially explicit ecological model to assess the population-level consequences of these effects on the abundance of the farmland bird species Skylark (Alauda arvensis). We also investigate the impacts of different land-use scenarios and aim to identify adaptive conservation options. We show that (1) the impacts of increased energy crop cultivation on Skylark population abundance depend strongly on the landscape structure; (2) impacts could be tolerated as long as a certain minimum level of crop-type heterogeneity is retained at the landscape level and (3) conservation actions are required and effective especially on landscapes where crop-field size is large.

Intensified cultivation of farmland is widely recognized to act negatively on many organisms, including birds as the Skylark (Alauda arvensis). During the last decades, this species has been showing a population decline of about 50-75 percent in northwestern Europe, including Sweden. One important factor that is considered to be a key driver of this decline is the switch from spring- to autumn-sowing of cereals. This change in farming practice has been shown to reduce food availability for skylarks and other species that rely on crop fields for foraging and nesting. To improve this situation, skylark plots (SPs), i.e. small (16-20 m2) unsown patches within winter cereal crops, have been developed in Great Britain during the last decade. The idea with SPs is to make it easier for skylarks to forage, since the sparser vegetation in SPs makes it easier to find food (i.e. invertebrates). From Great Britain the method has been shown to work well, increasing the breeding success of skylarks. However, the extent by which SPs contribute to improve breeding opportunities in Swedish arable farmland is unknown. There are structural differences in the agricultural landscapes of Sweden and Great Britain, with a higher relative proportion of spring sown cereals in Sweden. This might indicate that SPs have a lower positive effect when applied in Sweden, since the high proportion of spring cereals (sparser vegetation) makes it possible for skylarks to find food anyway. Thus it is important to study if SPs have a positive effect on skylarks in Sweden, before applying the method in a huge scale., In this study, the effect of SPs on the skylark territory density in autumn sown fields of wheat was studied. 15 study plots with SPs and 15 control plots without SPs situated on fields of similar size and surroundings were compared; temporal trends of invertebrate activity and vegetation height were used to examine whether the importance of SPs for territory density was there to be found and if this increased towards the end of the breeding season., The results indicate that SPs have a positive effect on the territory density of skylarks (total breeding season average in SP-sites 3.30 territories/3.14 ha, SE = 1.49; in control-sites 3.19 territories/3.14 ha, SE = 1.82), an effect that becomes clearer as time goes by. This indicates that the presence of SPs is enhancing the breeding season, making it possible for skylarks to produce multiple clutches. Invertebrate activity increased over time, at the same time as skylark territory density was decreasing. However, the decline of skylarks in SP-sites was less relative to control-sites, indicating that SPs makes the availability of food supplies (i.e. invertebrates) to increase. This pattern does also explain why SPs seems to have an increased positive effect as time goes by (increased vegetation density and hence lower food availability). Studies made in Great Britain do, however, indicate that SPs may have a larger positive effect when applied on larger fields situated in homogenous areas, a fact that have to be kept in mind when applying the method in a larger scale.

Numerous territorial species are less aggressive towards neighbours than strangers. This tolerance towards neighbouring conspecifics, termed the 'dear enemy' effect, seems to be a flexible feature of the relationship between neighbours, and has been shown to disappear in some species after experimental or natural modifications of the context. However, the maintenance over time of this singular relationship has been poorly studied. In this study, we followed the change of dear enemy relationships during the breeding season in a territorial songbird with a complex song, the skylark. We examined in the field the response of territory owners to playbacks of neighbour and stranger songs at three periods of the breeding season, corresponding to three ecological and social situations. Results showed that neighbours were dear enemies in the middle of the season, when territories were stable, but not at the beginning of the breeding season, during settlement and pair formation, nor at the end, when bird density increased owing to the presence of young birds becoming independent. Thus, the dear enemy relationship is not a fixed pattern but a flexible one likely to evolve with social and ecological circumstances.

Numerous territorial species are less aggressive towards neighbours than strangers. This tolerance towards neighbouring conspecifics, termed the 'dear enemy' effect, seems to be a flexible feature of the relationship between neighbours, and has been shown to disappear in some species after experimental or natural modifications of the context. However, the maintenance over time of this singular relationship has been poorly studied. In this study, we followed the change of dear enemy relationships during the breeding season in a territorial songbird with a complex song, the skylark. We examined in the field the response of territory owners to playbacks of neighbour and stranger songs at three periods of the breeding season, corresponding to three ecological and social situations. Results showed that neighbours were dear enemies in the middle of the season, when territories were stable, but not at the beginning of the breeding season, during settlement and pair formation, nor at the end, when bird density increased owing to the presence of young birds becoming independent. Thus, the dear enemy relationship is not a fixed pattern but a flexible one likely to evolve with social and ecological circumstances.

Between the spring of 2000 and winter of 2004, seasonal densities and the effect of wind farms on Skylark (Alauda arvensis) and Water pipit (Anthus spinoletta) were determined in mountainous areas in northern Galicia. The densities of the Skylark and Water pipit were between 5.9 birds/10 ha and 6.6 birds/10 ha respectively for the breeding period and between 2.1 birds /10 ha and 2.5 birds /10 ha respectively for the winter period. Only was detected a collision incidence for the Skylark of 0.007 birds/turbine/year.

The Skylark sounding rocket has been developed to produce a stable platform for high-altitude remote-sensing experiments. This Report describes the development and performance of photographic payloads carried on three Skylark rockets, one fired from Woomera, South Australia and two from Mercedes, San Luis Province, Argentina. The methods used for prediction of the performance of the photographic systems and the estimation of the required camera exposures are detailed. For each rocket firing the choice of photographic emulsions and filters is detailed and examples are given of the imagery obtained. Measurements made on the imagery have validated the methods used for the prediction of the performance of the photographic systems. The imagery has been assessed and interpreted by the Geography Department of the University of Reading and its findings are referenced. (Author)

A brief description of the star pointing attitude control system developed for the Skylark rocket is given. This is followed by a review of the possible sources of error which could affect the flight performance of the unit and an analysis of the accuracies in fact achieved with it during the flight of Skylark SL1011. The Report concludes by pointing out certain limitations of the system and, where practicable, suggesting possible solutions.

Eighteen existing sounding rocket systems are reported with a short description, a sketch with overall dimensions, weight and maximum acceleration data, and two performance charts - apogee altitude versus payload for various launch angles, and altitude versus time for various payloads at a launch angle of 88 degrees. The aim is to aid in the preliminary selection of a vehicle for a specific payload mission., Presented at the AGARD Specialists' Meeting on the Use of Rocket Vehicles in Flight Research held at the Kurnaus Hotel, Scheveningen, Holland on 18-21 Jul 1961 sponsored by the AGARD Fluid Dynamics Panel.

Contents: The Defence Research Establishment Atlantic, Radio Interference Problems in the Royal Navy, Canadian Defence Research Board Establishments--Change of Titles, Factors Contributing to the Impingement Corrosion of Copper-Nickel-Iron Sea Water Systems, The Weapons Research Establishment, Telemetry of Piston Parameters at Elecated Temperatures, Modern Man and Equipment in Antarctica, Computer-Type Stores for Sorting Data Files on a Quantitative or Ordinal Numerical Basis, Monitoring the Deep Oceans, NATO Operational Research Conference on Recent Developments in Lanchester Theory.

The Memorandum describes the determination of the attitude of the Skylark rocket, using a conical scanning sun-slit and an orthogonal array of magnetometers, at the time of a pulse from the sun-slit. There are two attitudes which satisfy the data. The correct solution must be chosen by appealing to other information e.g. continuity of the attitude motion. (Author)

Design and constructional details are given for a sensor suitable for fine guidance of sun pointing space vehicles. Factors affecting the accuracy and stability of the sensor are discussed and optimum values for certain critical parameters suggested for Skylark and satellite applications. Bias error measurement methods are described and it is concluded that, because of atmospheric turbulence, results using the real sun are unreliable; an alternative method using a solar simulator is presented which has given results repeatable to about 2 arc sec. (Author)

The paper presents the results of the analysis of contaminant releases made from two Skylark rockets fired on the morning and evening of 31st May, 1968. The wind profile, turbulent structure, temperature, and density of the atmosphere were determined. The significance of the results is discussed, in particular the diurnal variation. Some comments are made relating our observations to previous results - both of other workers and our own. (Author), Prepared in cooperation with Weapons Research Establishment, Salisbury (South Australia).

A three-axis star-pointing attitude control system has been developed for the Skylark sounding rocket. The system uses a simple strap-down inertial system to carry out precision manoeuvres to locate the target star, starting from an initial moon-pointing orientation. The star sensor is capable of providing adequate error information for stars down to visual magnitude 5. (Author)

This paper is submitted in an effort to acquaint the personnel of allied State agencies with related laws which control the public and private possession of live exotic and native wild animals. The need for this common knowledge of related laws by agencies with law enforcement responsibility is readily apparent when the annual number and related problems from imported or resident wild animals in California are examined. In addition to resident wild animal populations, millions of fish and thousands of mammals, birds, and reptiles enter California each year through the utilization of most methods of transportation. Most of these imported animals are exotic species from foreign lands which cannot be readily identified and pose various degrees of potential and actual threat to native wildlife, agriculture, and public health if they are introduced into the wilds of this State. For the purpose of this report, a general picture of imported exotic animals is presented in an introduction, and specific animals with related laws are treated individually under the headings of current laws and future regulations.

This paper is submitted in an effort to acquaint the personnel of allied State agencies with related laws which control the public and private possession of live exotic and native wild animals. The need for this common knowledge of related laws by agencies with law enforcement responsibility is readily apparent when the annual number and related problems from imported or resident wild animals in California are examined. In addition to resident wild animal populations, millions of fish and thousands of mammals, birds, and reptiles enter California each year through the utilization of most methods of transportation. Most of these imported animals are exotic species from foreign lands which cannot be readily identified and pose various degrees of potential and actual threat to native wildlife, agriculture, and public health if they are introduced into the wilds of this State. For the purpose of this report, a general picture of imported exotic animals is presented in an introduction, and specific animals with related laws are treated individually under the headings of current laws and future regulations.

Theodore Roosevelt did not know that skylarks were objectionable. He has always been hoping to see them increase on Long Island. He would like C. Hart Merriam to tell him what "to let in and keep out."

Theodore Roosevelt stands corrected, as he learned from Merriam that the song thrush and the titmouse are invasive.

Theodore Roosevelt knows that the blackbird was really a black thrush. He wishes it could be naturalized here. Roosevelt is glad that Richard Henry Tierney remembers his article on English birds. In the ninth chapter of his autobiography, Roosevelt speaks of the birds around Sagamore Hill.

William Dutcher, president of the National Association of Audubon Societies, sends President Roosevelt a report on skylarks recently completed by Beecher S. Bowdish.

President Roosevelt thanks William Dutcher, President of the National Association of Audubon Societies, and comments on the skylark.