Dissertations / Theses on the topic 'Farmland birds'

This thesis investigates nesting success, foraging behaviour, chick diet and growth of three ecologically contrasting species (skylark Alauda arvensis, yellowhammer Emberiza citrinella and song thrush Turdus philomelos) on farmland, in relation to microhabitat and the availability of invertebrates. Fieldwork was conducted on a lowland mixed arable farm in Leicestershire over the breeding seasons 2000 - 2002. Telemetry was used to monitor adult song thrushes and fledgling skylarks. Skylark nest density was highest in set-aside and lowest in crops, yellowhammer nest density was greatest in herbaceous vegetation and field margins whilst song thrush nest density was greatest in hedgerows and woodland. Birds did not utilise the available habitat at random for nesting. Provisioning skylarks and yellowhammers utilised managed set-aside strips more than would be expected, although both foraged in cereals. Song thrushes foraged primarily in woodland and boundary habitats, avoiding cereal crops, permanent pasture and set-aside. The largest cause of nest failure for each study species was predation. Skylark nest survival improved with increasing vegetation density at the nest site. Yellowhammer nest survival was affected by temperature and rainfall. Song thrush nest survival was affected by predator control, nest site location on the farm and habitat. Skylarks selected sparse vegetation and bare ground when foraging in winter cereals. Each species selected some invertebrate taxa over others, independently of chick age. Skylarks and yellowhammers did not forage in sites with greater invertebrate abundance than others, but song thrushes tended to forage in habitats with higher invertebrate biomass. Skylark chick growth rates were positively influenced by set-aside and negatively by spiders in the diet and the proportion of 'other habitats' around the nest. Skylark chicks with higher growth rates were more likely to fledge. No habitat effects or environmental factors were found to affect song thrush chick growth rates. Tagged skylark chicks exhibited a low post-fledgling survival rate, with most predated whilst flightless. This thesis identified actual and potential conservation benefits for nationally declining skylark, yellowhammer and song thrush populations arising from the management of cropped and non-cropped habitats.

Many species of farmland birds have shown huge declines in numbers and range since the 1970s due to agricultural intensification, and these declines have been worst amongst granivorous species. Recent studies have suggested that low abundance of invertebrate chick food may have been important in driving the declines of a number of granivorous species, however causation has still only been proved for the Grey Partridge, whose decline has been attributed to low chick survival due to the indirect effects of herbicides reducing invertebrate abundance. We investigated invertebrate declines and how they may have affected farmland bird populations in a number of ways. There is little long-term data on abundance of farmland invertebrates. Thus we first looked at how representative data from a long-running suction trap was of invertebrate abundance on local farmland. Suction trap catches reflected abundance of aerial invertebrates on local farmland, and also to abundance of epigeal invertebrates in many cases, particularly abundances in predominant crop types. Secondly, we looked at spatial and temporal distribution of invertebrates on farmland in order to make recommendations about how to increase invertebrate availability to farmland bird populations. Field margins were by far the most invertebrate rich habitats sampled. Most differences in invertebrate abundance between different crop types were found early in the season, at this time spring barley and spring oilseed rape had very low abundances. Winter wheat had relatively high invertebrate abundance compared to spring barley at this time. Winter oilseed rape and set-aside had relatively high abundances of the crop types sampled. We investigated how low invertebrate abundance may have affected populations of granivorous passerines by looking for evidence of reproductive trade-offs in a population of Tree Sparrows, and by supplementary feeding experiments with Tree Sparrow and Yellowhammer chicks. There was no evidence for reproductive trade-offs within years, conversely an effect of individual quality was found. There was some evidence of reproductive trade-offs between years. Supplementary feeding increased the mass of Tree Sparrow first broods early in May but not later in May, and also of chicks with yearling parents, who had a lower provisioning rate. Chicks fledged early in May had a lower survival rate to the following year than chicks fledged later, supplementary feeding and parental age had no effect on chick survival. Supplementary feeding a parent's first brood had no effect on their later reproductive output that season, or on their survival to the next breeding season. Supplementary feeding Yellowhammer chicks early season increased their mass, but had no effect later in the season. This complies with results from a previous study of Yellowhammers in southern England, which showed that a higher proportion of chicks fledge late in the season. Further analysis of this data showed that this was because chicks were more likely to starve early in the season, and also that chick mass was lower early season, even when just looking at chicks which went on to fledge. Thus, it would appear that low invertebrate abundance was affecting the granivorous passerines looked at most in the early season, and through chick mass and survival. Measures to increase invertebrate abundance at this time would be beneficial to populations of granivorous passerines.

1. Many species of bird breeding in Britain have declined in recent decades. However, only in the farmland ecosystem are the majority of species, primarily seed-eating passerines, declining. Similar declines in these species are also occurring elsewhere in Europe and North America. This thesis aims to model the effects of habitat change on population size ofthese species through an understanding of their behaviour. 2. A wide range of factors, primarily relating to the intensification of agricultural management, have been implicated in these declines, and these are reviewed in detail. There is little evidence for consistent impacts on the breeding biology, but considerable circumstantial evidence that declines in winter food supply have been a major cause of the declines. 3. Three species of seed-eating passerine are studied in detail, skylark Alauda arvensis, yellowhammer Emberiza citrinelia and com bunting Miliaria calandra. In winter, yellowhammers and com buntings used stubble fields exclusively; skylarks much preferred stubble fields. All avoided winter cereal fields. This is related to seed density, stubble fields held virtually all the cereal grain found in the soil and many more weed seeds than winter cereal fields. 4. The functional responses of skylarks, yellowhammers and com buntings are described. Seed availability plays an important role in determining intake rate, with seeds buried beneath the surface harder to obtain, particularly for yellowhammers. Seed availability has more general implications for the nature of functional responses. 5. Bird numbers were related to seed density, the aggregative response. The scale at which aggregative responses were observed varied between species. The availability of seeds in the soil column affected the birds use of fields, with the number of seeds on the surface important. The location of hedgerows was also important, yellowhammers and com buntings preferred to forage close to them, skylarks did not. 6. The general effects of overwinter mortality on population size are modelled and the effects of two causes of winter mortality, starvation and predation are analysed. Individuals traded-off these two risks which had an interactive effect on mortality. Density-dependence in the breeding season interacts with winter mortality to set population size. 7. The results presented in this thesis are used to model the effects of habitat changes on populations of seed-eating birds. The predicted population, on the basis of winter food supply, was close to the current actual population size. These models are used to assess the effectiveness of different management options, with unharvested conservation headlands being best for species such as the yellowhammer and tree sparrow Passer montanus, while set-aside is best for species such as the skylark.

l~:' . Abstract Fannland birds have undergone large declines in Britain and throughout Europe over the last fifty or so years. Green lanes (two hedgerows separated by an unmetalled farmland track) have only just begun to have their potential for wildlife recognised within farmland, with a few studies revealing their substantial benefits for butterflies, bees and wild flowers. This study examines the value ofgreen lanes for farmland birds, comparing 20 green hi.ries with paired single hedgerows around Chester, UK over the years 2002-2004. Green lanes were found to hold about three times as many breeding bird speCies, territories, and numbers as single hedgerows (P < 0.001). Significantly more birds were also recorded on the inside of green lanes than on the outside. Bird occurrence on green lanes was influenced by hedge width and surrounding land use. Significantly more nests were also found in green lanes than single hedgerows during the breeding seasons of 2003 and 2004. Predation rates were found to be similar for both field boundary tYPes when studied using artifiCial nests.

Grasshoppers and bush-crickets, collectively known as Orthoptera, are a critical invertebrate prey group for a number of declining farmland birds, including the cirl bunting (Emberiza cirlus). This study focuses on one species of Orthoptera, the meadow grasshopper (Chorthippus parallelus). The key objective was to provide an evidence base in order to identify the agri-environment scheme prescriptions and management practices of greatest value to C. parallelus. This information will help formulate management recommendations that will enhance C. parallelus abundance in agro-ecosystems, which in turn will contribute to the conservation of farmland birds. Comparisons between agri-environment pasture, 2m and 6m arable margins, longterm set-aside and intensively grazed pasture revealed that 6m margins and longterm set-aside tended to support significantly higher densities of adult C. paralle/us. The abundance of nymphs, however, did not appear to differ between the habitats surveyed. The abundance of C. parallelus adults and nymphs was influenced by a combination of sward architecture and botanical composition. Sward height was particularly important. Early stage nymphs preferred short swards, and as individuals matured sward height preferences shifted towards taller swards. Sward heights on agrienvironment pastures appear to be too short to benefit adult C. parallelus, whilst swards on arable margins are too tall to benefit nymphs. Mowing in July significantly reduced the abundance of C. parallelus adults and late stage nymphs, whereas mowing in May appeared to benefit early stage nymphs. The most critical and simplest improvement on current management practices would be to delay the mowing of grasslands and arable margins, which commonly occurs in July or August, until later in the season. It is proposed here that mowing should not be undertaken before September. Furthermore, results suggest that grazing on agrienvironment pastures should be lighter if higher abundances of C. parallelus are required to benefit farmland bird populations.

In this thesis, I aim to assess how farmland birds use insect-rich agri-environment scheme (AES) foraging habitats during the breeding season and how such birds might benefit from them. It is particularly focused on how the coverage and quality (measured by insect food levels and food accessibility) of AES habitats influence territory selection, foraging activities and breeding success. The thesis begins by explaining why farmland birds have declined, reviewing how AES may help reverse these trends, along with outlining why AES may fail to benefit breeding birds (Chapter one). I then investigated whether the addition of wildflowers to AES margins, boundary type, crop type, chick food availability or accessibility influenced the foraging activity of insectivores, mixed diet species and the passerine community in general (Chapter two). Next, I wanted to find out if territory selection by a declining farmland bird the yellowhammer Emberiza citronella related to the quantity of AES habitat available; models also accounted for chick food abundance, landscape diversity and nest site features (Chapter three). Subsequently I investigated how the availability of AES can affect chick diet and survival using the Eurasian tree sparrow Passer monatus as a focus species. I compared the abundance and diversity of tree sparrow chick food items between nest boxes with and without access to AES habitats aimed at foraging birds (Chapter four). I then documented whether tree sparrow productivity was limited by the availability of such invertebrate-rich foraging habitat (Chapter five). As the majority of AES studies use only short-term data sets, my final data chapter aimed to address this by linking trends in yellowhammer and common chaffinch Fringilla coelebs nest success to the total chick food abundance of available arable and AES habitats over an 10 year period (Chapter six). The thesis concludes by considering future research directions of AES and farmland bird studies in the United Kingdom (Chapter seven).

Agricultural environments are critical to the conservation of biota throughout the world. This is due both to the limited extent of current reserve systems and the large, and still expanding, proportion of terrestrial environments already dominated by agricultural land-uses. Consequently, there is a growing call from scientists around the world for the need to maximise the conservation value of agricultural environments. Efforts to identify key influences on the conservation status of fauna in agricultural landscapes have taken complementary approaches. Many studies have focussed on the role of remnant or semi-natural vegetation, and emphasised the influence on biota of spatial patterns in the landscape. Others have recognised that many species use diverse ‘countryside’ elements (matrix habitats) within farmland, and emphasise the benefits of landscape heterogeneity for conservation. Here, these research themes have been combined. This study takes a whole-of-landscape approach to investigating how landscape pattern and countryside heterogeneity influence the occurrence of birds in agricultural environments. Birds were sampled in 27 agricultural mosaics, each 1 km x 1 km in size (100 ha), in Gippsland, south-eastern Australia. Mosaics were selected to incorporate variation in two landscape properties: the cover of native vegetation, and richness of different types of element (i.e. land-uses/vegetation types). In each mosaic, 15 fixed sampling locations were stratified among seven different elements in proportion to their cover in the mosaic: native vegetation, linear vegetation, tree plantation, scattered paddock trees, pasture, wetlands and farm dams. Six point counts of birds were undertaken at all sample points in each mosaic: three each in the breeding and non-breeding months of a one-year period (October 2004 – August 2005). Independent measures of the composition, configuration, and heterogeneity of elements in the mosaic had differing effects on the richness of bird species recorded in these same mosaics. Sub-groups of birds based on habitat requirements responded most strongly to the extent of preferred element types in mosaics. Woodland birds (those of greatest conservation concern in farmland environments in Australia) were richer in mosaics with higher cover of native vegetation while open-tolerant species responded to the extent of scattered trees. In contrast, for total species richness, mosaic heterogeneity (richness of element types) and landscape context (cover of native vegetation in surrounding area) had the greatest influence. Mosaic structural properties also influenced the composition of entire bird assemblages in study mosaics. Avifaunal composition showed systematic variation along two main gradients which were readily interpreted in relation to landscape properties: 1) a gradient in the cover of wooded vegetation and, 2) the proportional composition of vegetation types in the mosaic. These gradients represent common trajectories of landscape modification associated with agricultural development: namely, the removal of wooded vegetation and the replacement of native species with exotic vegetation (e.g. crops and plantations). Species possessing different characteristics in relation to three avian life-history traits (nest type, feeding guild and clutch size) varied significantly in their position along these gradients of landscape modification. Species with different nesting requirements showed a strong relationship with the gradient in wooded vegetation cover while species belonging to different feeding guilds were influenced by the gradient defined by the replacement of native vegetation with exotic species. More bird species were recorded in native vegetation than in any other type of element sampled in this study. Nevertheless, most countryside elements had value for many species; particularly structurally complex elements such as scattered trees and tree plantation. Further, each type of landscape element contained different bird assemblages. Species that were recorded in a greater number of different types of landscape element were also recorded in more mosaics. This was true for all species and for woodland birds, and indicates that species that can use a greater range of countryside elements may have an increased tolerance of future landscape modification. The richness of woodland species at survey sites in different elements was influenced by features of the mosaic in which they occurred. Notably, the richness of woodland bird species recorded at sites in scattered trees and pasture increased with a greater cover of native vegetation in the overall mosaic. Of the overall pool of woodland bird species documented in the broader study region, 35% of species were not recorded in the agricultural mosaics sampled here. While many of these species were uncommon in the study area, or were associated with vegetation communities infrequently sampled in mosaics, this shows that conservation efforts in agricultural landscapes will not be appropriate for all species. For those woodland species that were recorded, measures of the extent of wooded vegetation cover had a strong, positive influence on the frequency of occurrence of individual species in mosaics. Thus, individual species of woodland bird occurred more frequently in mosaics with a greater cover of wooded vegetation. Nine woodland species showed a stronger response to measures of vegetation cover that included tree plantation and/or scattered trees than to the cover of native vegetation alone. For these species, structurally complex countryside elements provide valuable supplementary habitat at the landscape scale. Results of this study show that landscape properties influence the occurrence of birds in agricultural mosaics. The extent of cover of element types, particularly native vegetation, had the strongest influence on all measures of bird occurrence in mosaics. Thus, native vegetation is vital for the persistence of birds in farmland landscapes and is the primary element on which conservation efforts in these environments depend. Nevertheless, with careful management, countryside elements may provide additional conservation benefits for many bird species. Countryside elements made an important contribution to landscape heterogeneity, the landscape property with greatest influence on overall bird richness in mosaics. Countryside elements also increased the structural complexity of cleared agricultural land, and so have the capacity to enhance connectivity in fragmented landscapes. A focus on these factors (landscape heterogeneity and structural complexity) will provide the greatest opportunities for using countryside elements to increase the conservation value of farmland environments for native fauna. The relatively small scale of this study indicates that the cumulative effect of even small elements in farm mosaics contributes to the structural properties of entire landscapes. Critically, this emphasises the important contribution that individual landholders can make to nature conservation in agricultural environments.

High Nature Value farmland (HNVf) refers to traditional agricultural landscapes which support high levels of biodiversity. HNVf is declining across Europe, through both intensification and abandonment, raising concerns about the conservation of species associated with it. One argument is that such HNV species are better described as being dependent on disturbance, and that management practices on HNVf mimics the effects of natural disturbance processes such as herbivory, fire, severe weather and flooding, which are often suppressed across much of Europe. If true, one innovative approach for conserving HNV species would be to restore natural disturbance processes, as advocated by the "rewilding" conservation movement. I set out to explore the feasibility of this approach, focusing on flooding. Restoration of flood regimes is receiving growing attention, not only for its biodiversity benefits but also to reduce the risk of flooding in downstream urban areas, improve water quality, and increase the amenity value of rivers. I carried out four linked studies. Each followed a broadly similar approach: I selected sampling locations both in floodplain areas and comparable surrounding farmland, I surveyed birds and butterflies as indicator taxa of biodiversity, I carried out habitat mapping, and I estimated disturbance through both field measurements and remotely sensed data. My first study was around the Pripyat river in Ukraine, which has a large floodplain that has had minimal human intervention. I found that several, but not all, HNV species had higher population densities in the floodplain than in the surrounding HNV farmland, and several more had approximately equal population densities in the two habitats. This suggested intact flood regimes can retain some species that are elsewhere restricted to HNVf. My second study was around the river Rhône, France, where a restoration project has increased flow in floodplain channels and improved their connectivity with the main channel. I compared restored and non-restored segments of floodplain channel, as well as farmland and other habitats. While I found significant differences in population densitiesbetween habitat types, few species showed significant differences between restored and non-restored segments, suggesting that restoration had only limited ecological impacts on the wider landscape. My third study investigated a more ambitious restoration project which has reconnected a large area of floodplain to the river Peene in Germany. I found many HNV species had equal or higher population densities in the restored floodplain than in the surrounding unrestored farmland. This demonstrates that it is possible to restore the effect of natural flood disturbance on habitats and species. However, not all HNV species benefitted from flood-disturbed habitats, so clearly other conservation interventions need to be considered. For the final study, pooling data from all three sites I looked for associations between species' traits and environmental variables. My aim was to identify traits which predict species' responses to the environment, and hence which species are most likely to benefit from restoration. However, I did not find any significant associations in my data. In conclusion, I demonstrated that flood-disturbed habitats are suitable for many species traditionally associated with HNV farmland, and further that restoring flood disturbance processes can recreate those habitats. As such, reconnecting rivers and restoring floodplains would be a useful conservation intervention for species threatened by the abandonment or intensification of HNV farmland in Europe. However, other species did not benefit, and require other conservation interventions, perhaps other forms of rewilding, or continued incentivisation of favourable farming practices.

Reaching the EU target for renewable energy is likely to encourage a rapid expansion of biomass crop production in the UK. This expansion could pose a considerable threat to farmland birds, via the loss of suitable nesting habitat for ground-breeding birds or by decline in availability and accessibility of foraging resource for other farmland birds. Alternatively, the low-input management of biomass crops may provide benefits over more intensively managed arable crops. The potential impacts of biomass expansion on nesting and foraging opportunities were therefore investigated by examining the nesting success of lapwings (Vanellus vanellus) in Miscanthus, and the faecal components of songbirds nesting in boundaries of Miscanthus and short rotation coppice (SRC) willow fields. Despite similar nest densities and field occupancy across crop types, lapwing clutches experienced lower hatching success in Miscanthus fields than in arable crops. This result was mainly influenced by increased losses in 2012; a particularly wet breeding season. In years of already unfavourable breeding conditions, nests in Miscanthus may therefore be more vulnerable and suffer higher predation rates than those in arable crops. More invertebrates were found in SRC crop than in Miscanthus, and this was reflected in the faeces of whitethroat (Sylvia communis) chicks nesting in the boundaries of SRC and Miscanthus fields. Despite lower availability of Coleoptera in Miscanthus fields than SRC, this was not reflected in faeces of whitethroats or yellowhammers (Emberiza citronella), suggesting birds nesting in Miscanthus may supplement chick diet with food found elsewhere. Converting land to biomass crop cultivation may pose some risk to farmland birds, but while nesting and foraging opportunities may be limited in Miscanthus crop, SRC provides a more abundant foraging resource. The extent of any risk will depend on the crops being replaced, the position of biomass crops within the landscape and the extent of biomass crop uptake throughout the UK. It is vital that government energy targets are met in a sustainable manner, which could be achieved if the expansion of the industry is managed sensitively.

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 habitat. The same species except Eurasian tree sparrow were modelled with the generalized N-mixture model of Dail and Madsen (2011) to evaluate what is influencing abundance, recruitment rates, survival probabilities and detectability over five years. The day of the season affected the detectability of almost all species. The effect of habitat on recruitment rate and survival probability, however, could only be shown for yellowhammer. For the latter, proportion of meadow affected recruitment and proportion of reed affected survival. In conclusion, the presence of species seems to be generally higher in habitats associated with low-intensity farming on the single season scale. Over time, however, a significant effect on population dynamic parameters for the same species could not be shown for most species. This could be a result of insufficient data for each year, too few years of data, or that the tested habitat types are not affecting these parameters over time.

Extensive farmland ecosystems are widespread and biodiversity-rich, yet they face important human pressures since the beginning of agriculture intensification, which is leading them into a severe biodiversity crisis. As a result, farmland bird populations - particularly specialist species such as steppe birds - are declining dramatically. In Europe, steppe birds are associated with “cereal steppes”, which are extensive agricultural landscapes where crop rotations include fallow fields. Fallows are key breeding and foraging habitats for farmland birds and usually present open vegetation structures essential for steppe birds. This thesis, situated in a cereal steppe in Catalonia (north-eastern Spain), evaluates the importance of fallow land and its management for enhancing farmland and steppe bird populations. Because population monitoring is key to evaluate the status of populations, I also explored the importance of accounting for imperfect detection when estimating farmland bird population trends. By using a Hierarchical Distance Sampling (HDS) model, I found that heterogeneous detection across observers and years could bias trend estimates when not accounted for. Through a HDS community model integrating data of 37 farmland bird species, I revealed the lack of efficiency of conservation measures applied in fallow fields, currently promoted by the European Common Agricultural Policy (Agri-Environmental Schemes and Greening), to increase farmland bird abundance. However, a local conservation measure targeted specifically at steppe birds (Targeted Fallow Management, TFM) ‒ consisting of agricultural practices on fallows applied once or twice annually before the breeding season ‒ enhanced steppe bird abundance. Through path analyses, I could disentangle the mechanisms behind TFM success and found that TFM fulfils species-specific requirements by modulating the vegetation structure. Finally, I used the first GPS data on the declining Pin-tailed sandgrouse (Pterocles alchata) to demonstrate the importance of fallow land during the breeding season, when cereal vegetation is tall and unsuitable for steppe birds causing a habitat bottleneck. This thesis provides applied guidelines for conservation planning, from population monitoring to mechanisms involved in the success of specific conservation measures. The key finding is the importance of promoting not only fallow- land presence, but also its management, to improve its conservation efficiency. These guidelines have great potential to be included within the upcoming European agricultural reform (CAP post- 2020) and help prevent imminent population and species extinctions.
Els paisatges agrícoles són ecosistemes rics en biodiversitat, però des de mitjans del segle passat Europa pateix un procés d'intensificació agrícola que està causant la pèrdua d'aquesta biodiversitat a gran velocitat. Com a conseqüència, les poblacions d'ocells de medis agrícoles ‒ en particular espècies especialistes com els ocells estèpics ‒ pateixen un fort declivi. A Europa, els ocells estèpics estan estretament associats a les estepes cerealistes de la Península Ibèrica, que són paisatges oberts i plans on predomina el cultiu del cereal, en rotació amb guarets i altres cultius herbacis. Els guarets són hàbitats essencials per a l'alimentació i nidificació dels ocells de medis agrícoles, i normalment presenten una vegetació baixa en altura i cobertura que resulta òptima per els ocells estèpics. Aquesta tesi avalua la importància del guaret i la seva gestió per a la millora de les poblacions d'ocells agrícoles i estèpics. L'estudi es desenvolupa en una estepa cerealista de Catalunya (nord-est d'Espanya) en la qual s'apliquen mesures compensatòries per a la conservació d'ocells estèpics des de l'any 2015. En aquest context, la tesi també explora la importància de tenir en compte la detectabilitat per a l'estima de tendències poblacionals d'ocells en ecosistemes agrícoles, ja que el monitoratge és un aspecte essencial per avaluar l'estat de les poblacions. La tesi demostra l'eficiència d'una mesura de conservació d'àmbit local específicament dissenyada pels ocells estèpics, que consisteix en la gestió de guarets (“Targeted Fallow Management, TFM”). Mitjançant l'ús d'anàlisi de ruta (“Path analysis”), aquesta tesi revela el mecanisme ecològic d'actuació de la mesura TFM, que satisfà els requeriments específics de diferents espècies d'ocells estèpics mitjançant una gestió adequada de l'estructura de la vegetació. A més, TFM va resultar ser més eficaç que les mesures de conservació en guarets promogudes en el marc de la Política Agrària Comuna Europea (Greening i Mesures Agroambientals) per augmentar l'abundància de la comunitat d'ocells, especialment dels ocells estèpics. Aquests resultats s'han obtingut mitjançant l'aplicació de models jeràrquics de mostreig per distàncies (“Hierarchical Distance Sampling, HDS”). També s'utilitzen els models HDS per demostrar que l'existència d'una detecció heterogènia entre observadors i al llarg dels anys pot ocasionar estimes de tendències poblacionals errònies si no es té en compte la detecció imperfecta. Finalment, utilitzant dades GPS de ganga (Pterocles alchata), també es demostra la importància del guaret quan el creixement del cereal a la primavera ocasiona un coll d'ampolla en la quantitat disponible d'hàbitat òptim per aquesta espècie. Aquesta tesi proporciona recomanacions útils per la planificació de mesures de conservació, des de l'etapa inicial del monitoratge fins a comprendre quins són els mecanismes ecològics subjacents a les mesures de conservació més exitoses. La seva principal contribució és la importància d'una adequada gestió dels guarets per augmentar el seu valor com a eina de conservació. Aquestes recomanacions són especialment oportunes per poder ser incloses en la nova reforma de la Política Agrària Comuna, i així contribuir a la conservació d'aquestes espècies.
Los paisajes agrícolas son ecosistemas ricos en biodiversidad, pero desde mediados del siglo pasado Europa sufre un proceso de intensificación agrícola que está causando la pérdida de esta biodiversidad a gran velocidad. Como consecuencia, las poblaciones de aves de medios agrícolas ‒ en particular especies especialistas como las aves esteparias ‒ sufren un declive alarmante. En Europa, las aves esteparias están estrechamente asociadas a las estepas cerealistas de la Península Ibérica, que son paisajes abiertos y llanos en los que predomina el cultivo del cereal, en rotación con barbechos y otros cultivos herbáceos. Los barbechos son hábitats esenciales para la alimentación y nidificación de aves de medios agrícolas, y normalmente presentan una vegetación baja en altura y cobertura que resulta óptima para las aves esteparias. Esta tesis evalúa la importancia de las tierras en barbecho y su manejo para la mejora de las poblaciones de aves de medios agrícolas y esteparios. El estudio se desarrolla en una estepa cerealista de Cataluña (noreste de España) en la que se aplican medidas compensatorias para la conservación de aves esteparias desde el año 2015. En este marco, la tesis también explora la importancia de tener en cuenta la detectabilidad para la estima de tendencias poblacionales de aves en ecosistemas agrícolas, ya que el monitoreo es un aspecto esencial para evaluar el estado de las poblaciones. La tesis demuestra la eficiencia de una medida de conservación de ámbito local, específicamente diseñada para las aves esteparias, consistente en el manejo de barbechos (“Targeted Fallow Management, TFM”). Mediante el uso de análisis de ruta (“Path analysis”), esta tesis revela el mecanismo ecológico de actuación de la medida TFM, que satisface los requerimientos específicos de distintas especies de aves esteparias mediante una gestión adecuada de la estructura de la vegetación. Además, TFM resultó ser más eficaz que las medidas de conservación en barbechos en el marco de la Política Agraria Común Europea (Greening y Medidas Agroambientales) para aumentar la abundancia de la comunidad de aves, en especial de las aves esteparias. Estos resultados se han obtenido mediante la aplicación de modelos jerárquicos de muestreo por distancias (“Hierarchical Distance Sampling, HDS”). También se utiliza HDS para demostrar que la existencia de una detección heterogénea entre observadores y a lo largo de los años puede ocasionar estimas de tendencias poblacionales erróneas para ciertas especies, si no se tiene en cuenta la detección imperfecta. Finalmente, utilizando datos GPS de ganga ibérica (Pterocles alchata), también se demuestra la importancia del barbecho cuando el crecimiento del cereal en primavera ocasiona un cuello de botella en la cantidad de hábitat óptimo disponible para esta especie. Esta tesis proporciona recomendaciones útiles para la planificación de medidas de conservación, desde la etapa de monitoreo hasta comprender cuáles son los mecanismos ecológicos subyacentes a las medidas de conservación más exitosas. Su principal contribución es la importancia de una adecuada gestión de los barbechos para aumentar su valor como herramienta de conservación. Estas recomendaciones son especialmente oportunas para ser incluidas en la nueva reforma de la Política Agraria Común, y así contribuir a la conservación de estas especies.

During the past several decades, agricultural intensification has been crucial to increase the food supply. Several processes related to intensification are very detrimental to the environment, particularly biodiversity. Today, agriculture is facing the challenge of satisfying its demand for food while improving its environmental sustainability. Knowledge of the shape of the relationship between biodiversity and intensity is necessary to determine both where conservation policies will be most effective and how to allocate intensity to reconcile production and biodiversity. Few empirical studies on this relationship exist, and the influence of the spatial arrangement of intensity on biodiversity remains untested. This Ph.D. thesis determined how to target both agricultural intensity and its spatial allocation for meeting production and conservation objectives of farmlands. To answer this research question, we used a country-scaled approach that combined two France-scaled databases that describe agriculture and farmland birds. We characterized a nationwide gradient of agricultural intensity and studied a farmland bird community along this gradient, using several trait-based descriptors (specialization, trophic level, and species main habitat). Agricultural intensity and bird communities were described at the Small Agricultural Region (SAR; mean width = 22.4 km) level. As a first step, we developed a novel method to estimate an intensity indicator that was based on Input Costs/ha, with SAR resolution. This indicator provides a continuous intensity measure that is relevant across different types of agricultural systems. Secondly, we investigated the effects of a gradient of land uses (grassland to arable land) and its heterogeneity on the bird community. We found habitat specialists suffered from habitat loss, while generalists benefited from heterogeneity. Thirdly, we showed that the community responded significantly to intensity, with winner species replacing loser species along the gradient. The shift between losers and winners was sharper at low intensities. Interestingly, spatial aggregation of intensity had a strengthening effect on the bird community. Finally, the relationships linking intensity to the bird community, food production, and economic performance were integrated into a model aimed at optimizing intensity allocation. Optimal allocations reached win-no-lose solutions with the three criteria. They corresponded to targeted intensity modifications: many small changed, favoring homogeneous, extensive clusters, were optimal within an extensification scenario; while a few large changes, favoring heterogeneity, were optimal within an intensification scenario. We provide one of the first studies demonstrating that spatial aggregation of intensity can influence the biodiversity/intensity relationship. Our results also provide an opportunity to improve the effectiveness of conservation policies, at national scales, with spatial targeting: opposite targeting should be performed either to maximize biodiversity benefits or to increase production, while mitigating biodiversity impacts. Our results highlight the importance of mixed allocation strategies between land sparing/sharing extremes. In order to put these opportunities into effect, further research should address the technical solutions that achieve intensity modification at the farm level and design targeted policies that benefit biodiversity and other environmental criteria

L'objectif de cette thèse est de comprendre comment l'hétérogénéité du paysage (i.e. composition, structuration spatiale et dynamique temporelle) affecte les populations, notamment dans les paysages agricoles, fortement structurés par la mosaïque des parcelles et les rotations culturales. Nous abordons cette question à la fois de manière théorique (en simulant des dynamiques de populations dans des paysages aux propriétés spatiales et temporelles contrôlées) mais également empirique (en analysant la sélection d'habitat par la communauté de passereaux des paysages agricoles).Nous avons ainsi montré que la composition, la configuration spatiale et la dynamique temporelle étaient toutes trois importantes pour expliquer les dynamiques de population, et que la nature des réponses à l'hétérogénéité dépendait des traits des espèces (taux de croissance, dispersion, échelle de réponse au paysage). L'analyse sur la communauté de passereaux a montré que la composition en cultures influençait la sélection d'habitat chez certaines espèces, mais nos données ne nous ont pas permis de mettre en avant un effet significatif de la structuration spatiale des cultures sur les passereaux. Une analyse plus fine pour l'Alouette des champs (Alauda arvensis) a montré un effet positif de la diversité des cultures à l'échelle du territoire, expliqué par une complémentarité fonctionnelle entre les cultures, suggérant que des petites parcelles et un mélange des cultures dans le paysage seraient bénéfiques pour cette espèce. L'effet de la structuration spatiale et temporelle des cultures sur les populations mériterait d'être testé de façon plus approfondie à l'échelle adéquate sur de nombreux taxons. Une meilleure connaissance de l'effet des propriétés de la matrice cultivée sur les processus permettrait de prédire l'évolution des populations face à des modifications du paysage à l'aide de modèles mécanistes, et offrirait de nouvelles opportunités pour gérer la biodiversité
The aim of this thesis is to understand how landscape heterogeneity (i.e. composition, configuration and temporal dynamics) affects populations, especially in farmlands, highly structured by the crop mosaic and rotations. We answer this question theoretically (simulating population dynamics in landscapes with controlled spatial and temporal properties) and empirically (analysing habitat selection by the farmland bird community).We found that landscape composition, configuration and temporal dynamics were all important to explain population dynamics and that the response to landscape heterogeneity depended on species traits (growth rate, dispersal, scale of response to the landscape). The analyse of farmland birds data revealed that crop composition influenced habitat selection for some species, but did not reveal a significant effect of crop configuration on birds. A finer analyse on Skylark showed a positive effect of crop diversity at the territory scale explained by a functional complementation among crops. It suggested that small fields and crop well mixed in the landscape would be beneficial for this species. The effect of spatial and temporal crop heterogeneity should be studied in depth at the right scale on many taxa. A good understanding of the effect of the cultivated matrix on processes would allow us to predict the change in populations when modifying the landscape and would offer new opportunities to manage biodiversity

Worldwide degradation and conversion of tropical forests affects many species and their provided ecosystem services. Among them are birds, responsible for pollination, seed dispersal, pest control and scavenging. This study, conducted in southwest Ethiopia, compares species composition and bird functional diversity between forest and homegardens close to and far from forest, both in terms of species numbers and bird abundances. Point counts and mist netting were used to obtain data. While the former method detected more species, abundance data from the latter revealed patterns not observed by just comparing species numbers. I found that species diversity was lower in forest compared to gardens and that the species composition of both communities was significantly distinct. Whereas forest had more forest specialists, gardens held more forest visitors and species of open country. Close and far gardens did not differ in any aspect, except that abundances of forest generalist birds were somewhat higher close to forest. Regarding bird feeding guilds, I found that granivores and nectarivores were more numerous in gardens, while frugivores were more common in forest. Carnivores and omnivores showed no effect. Insectivore proportions were the same for forest and farmland, but their numbers (including those of all sub-guilds) were higher in gardens. The Ethiopian forest avifauna is poor in comparison with other Afromontane regions, lacking several, mostly insectivorous genera. This could be the result of an extinction after which its geographic isolation made recolonization difficult, especially for dispersal-limited understory species. Nonetheless, and despite their impoverished state, the results suggest that forest remnants are important for forest-dependent species, being a stronghold for forest specialists and supporting higher numbers of forest generalists in nearby gardens. However, future forest regrowth might be at stake with ongoing agricultural encroachment, because gardens hold fewer frugivores, especially forest specialists, which might affect seed dispersal.
Många arter påverkas negativt av avskogning och annan mänsklig påverkan på tropiska skogar, vilket också kan få konsekvenser för de ekosystemtjänster dessa arter levererar. En viktig artgrupp i detta avseende är fåglar, som kan ha betydelse för pollination, fröspridning, naturlig skadedjurskontroll och som asätare. Denna studie, utförd i sydvästra Etiopien, jämför artsammansättning och funktionell diversitet hos fåglar i skogar och trädgårdar både nära och långt ifrån skogen. Både antal arter och antal individer har undersökts. Data materialet bygger både på observationer från punktinventering och fåglar fångade med slöjnät. Med den första metoden noterade jag fler arter, medan abundansvärden från den andra metoden gjorde att jag såg mönster som inte syntes vid endast jämförelser av artrikedom. Jag fann att artrikedomen var lägre i skogen i jämförelse med trädgårdarna, men att artsammansättningen var signifikant skiljd däremellan. Skogarna hade fler skogsspecialister medan trädgårdarna hade fler arter från öppna marker och tillfälliga skogsbesökande arter. Trädgårdar som låg nära eller långt ifrån skogen skiljde sig inte på något sätt utom att individtätheten av skogsgeneralister var något högre i trädgårdar nära skogen. När det gäller uppdelningen av fåglarna utifrån vad de äter så fann jag att fröätande och nektarätande arter var vanligare i trädgårdar medan fruktätande arter var vanligare i skogen. Rovfåglar och allätare uppvisade inget tydligt mönster. Proportionen insektsätande fåglelarter var samma i skogen och trädgårdarna, men det absoluta antalet arter (inklusive alla olika underkategorier) var högre i trädgårdarna. Den etiopiska skogsfågelfaunan är artfattig i förhållande till andra bergstrakter i Afrika och saknar flera släkten av framförallt insektsätande fåglar. Detta skulle kunna bero på ett tidigare utdöende varefter en senare återkolonisering varit svår på grund av den geografiska isoleringen, speciellt för insektsätande fåglar som huvudsakligen finns i undervegetationen. Trots den relativa artfattigdomen så visar resultatet från min studie hursomhelst på att skogarna är viktiga för skogsberoende fåglar. Den största betydelsen har de för skogsspecialister där, men även genom en positiv effekt på abundansen av skogsgeneralister i närliggande trädgårdar. Dock kan framtida återväxt av skogar bli problematisk på grund av en pågående omvandling av skogar till trädgårdar, eftersom trädgårdar hyser färre fruktätande fåglar, vilket kan påverka fröspridning över landskapet.
Examining mismatches between management and the supply of ecosystem services in Ethiopian agroecosystems across scales in space and time

Depuis plusieurs décennies, le déclin des oiseaux spécialistes des milieux agricoles anime le monde scientifique à travers une large documentation sur les causes et les conséquences de ce phénomène. Une des questions clefs porte sur la part de responsabilité des pesticides dans cette tendance, car les études menées jusqu’ici indiquent des relations de cause à effet sans pour autant identifier clairement les mécanismes sous-jacents. L'un des défis majeurs est donc de fournir des faits pertinents sur le plan biologique pour une meilleure évaluation des risques liés aux pesticides pour les oiseaux des champs. Ainsi, le but de cette thèse était d’appréhender les effet sublétaux des pesticides sur les traits d’histoire de vie de la perdrix grise (Perdix perdix) à la fois à l’aide d’expérimentations en conditions contrôlées mais aussi de suivi d’individus sauvages. Associée à la survie et à la reproduction, l’approche multi-trait réalisée ici a permis d’appréhender (1) les effets négatifs des pesticides sur plusieurs traits d’histoire de vie des perdrix, à la fois en captivité mais aussi in natura, (2) l’omniprésence de cocktails de pesticides dans le sang des oiseaux et leurs liens avec les effets sublétaux, (3) l’importance de prendre en compte les processus évolutifs dans les effets à long terme des pesticides en considérant les effets parentaux et la plasticité phénotypique des individus et enfin (4) la nécessité d’utiliser le biomonitoring des espèces sentinelles pour un meilleur suivi de la contamination des agroécosystèmes à l’échelle locale mais aussi comme outil de développement et de mise en place de zones refuges à l’exposition aux pesticides
For several decades, the farmland bird decline has been the subject of much scientific attention, with a large body of literature on the causes and consequences of this phenomenon. One of the major issue is whether pesticides are responsible for this trend, as studies conducted so far indicate cause and effect relationships without clearly identifying the underlying mechanisms. A major challenge is thus to provide biologically relevant evidences for a better assessment of pesticide-related risks to farmland birds. The aim of this thesis was to study the sublethal effects of pesticides on the life history traits of the grey partridge (Perdix perdix) using both experiments under controlled conditions and monitoring of free-living birds. In combination with survival and reproduction, the multi-trait approach carried out here allowed us to understand (1) the deleterious effects of pesticides on several life history traits of partridges, both in captivity and in natura, (2) the ubiquity of pesticide cocktails in the blood of birds and their links with sublethal effects, (3) the importance of considering evolutionary processes in the long-term effects of pesticides by considering parental effects and phenotypic plasticity of individuals and finally (4) the need to use biomonitoring of sentinel species for a better monitoring of the contamination of agroecosystems at the local scale but also as a tool for the development and implementation of refuge areas to pesticide exposure

The Corn Bunting Emberiza calandra is one of the most severely declining farmland birds across Europe. In the UK, numbers fell by 86% between 1967 and 2008. Corn Buntings favour open landscapes, nest on or close to the ground, are often polygynous, double-brooded, and have a seed-based diet supplemented in summer by invertebrates. This study investigated the recent causes of decline in arable and mixed farmland in eastern Scotland, and sought to identify potential conservation solutions that could be delivered through agri-environment schemes (AES). Combining new data with analyses of existing long-term datasets, I investigated habitat associations during summer and winter, the timing and success of nesting attempts, and measured reproductive and population responses to AES. Corn Buntings declined almost to extinction in one study area where, over 20 years, the main recorded intensifications of farming were reduced weed abundance within crops and removal of boundaries to make bigger fields. Territory locations, late-summer occupancy and polygyny were all strongly associated with weedy fields. There were also positive associations with overhead wires and in early summer with winter barley and forage grasses. Late-summer occupancy was associated with spring-sown cereals, crops that are amongst the last to be harvested. Changes in habitat associations and to aspects of the mating system as the population declined and agriculture intensified are discussed. Intensive monitoring showed that Corn Buntings laid clutches from mid-May to mid-August, mostly in fields of forage grasses and autumn-sown cereals in early summer, and spring sown cereals in late summer. A preference for nesting in dense swards explained this seasonal variation. Breeding success in forage grasses was poor, due to high rates of nest loss during mowing. However, in experimental trials, nest success in fields with delayed mowing was fivefold that of control fields. With sufficient uptake through AES, delayed mowing could raise productivity to levels required to reverse population declines. In winter, cereal stubbles and AES unharvested crop patches were the main foraging habitats used. Unharvested crops with abundant cereal grain in their first winter of establishment were favoured. Population monitoring over seven years and 71 farms revealed increases on farms with AES targeted at Corn Buntings, no significant change on farms with general AES, and declines on control farms. In arable-dominated farmland, management that increased food availability reversed declines, but on mixed farmland where Corn Buntings nested in forage grasses, delayed mowing was essential for population increase. This study has already influenced the design of AES targeted at Corn Buntings in Scotland, and I make further recommendations for the species’ conservation and design of AES that are applicable to farmland throughout Britain and Europe.

The thesis presents data from bird monitoring, carried out in agricultural landscape in borderland of Southern Moravia (Czech republic) and Lower Austria (Austria). Relations among habitats and bird species richness and abundance are studied and data from both countries compared.

Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia
Socioeconomical changes from recent decades in Mediterranean farmland habitats have caused the abandonment of less fertile arable land in many regions. Together, these relatively recent changes in land use patterns have progressively resulted in the loss and fragmentation of many arable habitats for farmland birds. In this thesis I evaluated the consequences of habitat fragmentation driven by land use changes in a pseudo-steppe area in Southern Portugal. Land use changes included afforestation of arable habitats, land abandonment and land intensification. I outlined different approaches to study the effects of the mentioned changes in the farmland community in the Special Protection Area of Castro Verde. Overall results suggested that changes like afforestation may have opposite impacts in the community. Indeed, bird diversity within the area increased, including positive effects in woodland, farmland and ground-nesting birds. Conversely, steppe birds were negatively affected, including species of conservation concern. Also, this study showed that grassland specialists (e.g., Melanocorypha calandra) are very sensitive to current trends of habitat fragmentation. Moreover both habitat fragmentation and grazing regimes are major drivers of grassland breeding densities. Finally, this work supports the view that the conservation and management of steppe birds in Mediterranean farmland requires a multiscale approach.
Fundação para a Ciência e Tecnologia/Portuguese Science Foundation (FCT): Luís Reino was fully funded by the PhD grant (SFRH/BD/14085/2003) funded by the POCI 2010. Project PRAXIS XXI/C/AGR/11063/98 “Determinants of biodiversity in fallows of pseudosteppes: implications for the definition of agri-environmental management rules” funded field work carried out in 2000/2001 (before my PhD grant was conceded) and all data analysed in the article of Chapters 3 and partially in the article of Chapter 4 (2000/01).

Farmland bird populations in Europe have been in decline for a long time. Agricultural intensification and growing a large share of crops that provide suboptimal breeding habitat could be the main causes of the observed decline. To explore these possible drivers, I focused on population trends of farmland bird species in different habitats in the Czech Republic over the periods 1982-1990 and 1990-2010. Specifically, I focused on the variability in trends within each species in respect to the differences in landscape management between the lowlands and mid-altitude areas before and after 1990. The expected effect of intensive farming in the lowlands until 1990 was reflected by a strong decline in populations of Northern Lapwing and Yellowhammer. The influence of less intensive farming in mid-altitude areas causing moderate population decline was confirmed rather by shrubs and trees species than farmland specialists. After 1990, less intensive farming in the lowlands should reduce the decline, which may have occurred, but compelling comparison of population trends between the two time periods was not possible for most species due to the lack of data. On the contrary, more intensive population decline in mid-altitudes after 1990, which should be the response to arable land abandonment, was not...

abstract: The Great Bustard (Otis tarda) is an iconic species of the temperate grasslands of Europe and Asia, a habitat that is among the least protected ecosystems in the world. A distinct subspecies, the Asian Great Bustard (O. t. dybowskii), is poorly understood due to its wary nature and remote range in Siberia, Mongolia, and northern China. This subspecies is now endangered by rapid development. Using satellite telemetry and remote sensing, I investigated three aspects of the Asian Great Bustard’s ecology critical to its conservation: migratory routes, migratory cues, and habitat use patterns. I found that Asian Great Bustards spent one-third of the year on a 2000 km migratory pathway, a distance twice as far as has previously been recorded for the species. Tracked individuals moved nomadically over large winter territories and did not repeat migratory stopovers, complicating conservation planning. Migratory timing was variable and migratory movements were significantly correlated with weather cues. Specifically, bustards migrated on days when wind support was favorable and temperature presaged warmer temperatures on the breeding grounds (spring) or advancing winter weather (fall). On the breeding grounds, Asian Great Bustards used both steppe and wheat agriculture habitat. All recorded reproductive attempts failed, regardless of habitat in which the nest was placed. Agricultural practices are likely to intensify in the coming decade, which would present further challenges to reproduction. The distinct migratory behavior and habitat use patterns of the Asian Great Bustard are likely adaptations to the climate and ecology of Inner Asia and underscore the importance of conserving these unique populations. My research indicates that conservation of the Asian Great Bustard will require a landscape-level approach. This approach should incorporate measures at the breeding grounds to raise reproductive success, alongside actions on the migratory pathway to ensure appropriate habitat and reduce adult mortality. To secure international cooperation, I proposed that an increased level of protection should be directed toward the Great Bustard under the Convention on Migratory Species (CMS). That proposal, accepted by the Eleventh Conference of Parties to CMS, provides recommendations for conservation action and illustrates the transdisciplinary approach I have taken in this research.
Dissertation/Thesis
Doctoral Dissertation Biology 2015

碩士
國立中興大學
園藝學系所
107
In recent years, Taiwan''s rapid economic development, as well as the urban planning area continued being allocated, resulting in diverse land use patterns. On top of that, farmland is constantly converted to construction sites, roads or other land types, not only decreasing natural functions of agricultural ecosystems but also influencing living organisms accordingly. In order to promote rational allocation of agricultural land resources, to protect prime farmlands and to ensure sustainability, it is necessary to identify ecological characteristics and types of the spatial distribution of agricultural land, and establish a proper evaluation and decision-making system for regional planning. The purpose of this study is to understand habitat suitability of farmland bird guilds on agricultural landscapes in Chiayi County. The approach is firstly to analyze bird observation data from 1993 to 2019; secondly, to investigate distribution and species richness of farmland bird guilds; then, to define habitat environmental factors of based on literature reviews and expert opinions. Afterward, each factor is ranked and assigned a score. The Analytic Network Process (ANP) is used to establish a standard structure and criteria of habitat suitability assessment and to obtain evaluating values for 19 selected factors under different scenarios of conservation practices. Values derived by ANP are applied as weight coefficients into evaluating habitat suitability for farmland bird guilds in agricultural areas. Lastly, I performed one-way analysis of variance (ANOVA) to verify the reliability of the evaluation method. The Super Decisions, decision support software, is implemented to conduct the expert questionnaire analysis. Results show that conservation strategy II, "Practicing ecological or environmental friendly farming," earns higher weight value (0.55361), and therefore can be considered as the priority choice for conservation strategy. Also, findings of this research indicated that these three factors, habitat integrity (0.01418), farmland landscape heterogeneity (0.01203) and bird abundance (0.00730) present significantly influence on habitat suitability assessment. Bird observation data of 2017 to 2019 are applied to perform ANOVA, particularly, cross-checking with results of habitat suitability assessment regarding spatial distribution of bird occurrences and environmental conditions. The mean value shows significant, verifying the reliability of this approach.

Various types of woody vegetation are a key biodiversity refugee in intensively managed agricultural landscapes. However, the role of woodlots, representing an important type of such a vegetation, remains overlooked so far. Whereas the previous studies focused on the effect of their area, shape and isolation, consequences of variation in their habitat quality for biodiversity were not assessed up to now. This thesis is thus one of the first studies focusing on woodlots as a specific habitat for birds in agricultural landscape. My goals were: (I) to find out what is the bird community composition of woodlots in a Czech landscape, (II) to find out, what are the key habitat predictors of bird species richness and abundance in woodlots, (III) to describe differences in habitat preferences among various guilds and (IV) to formulate recommendations for conservational practice. I surveyed birds in 82 woodlots in an intensively managed landscape in Central Bohemia, Czechia, and measured variables describing woodlots' habitat quality together with woodlots' area, shape, isolation and types of surrounding land-use. I recorded numerous forest and non-forest bird species (57 in total), including some endangered farmland birds. The habitat variables showing significant relationships to bird community...

The populations of many farmland birds have severely declined during the past years. Even (formerly) common species such as the Eurasian Skylark (Alauda arvensis) and the Northern Lapwing (Vanellus vanellus) are strongly affected. The declines were mainly caused by agricultural intensification. In response to the declines, agri-environmental schemes (AES) that integrate protection objectives into agricultural practices are a promising strategy. Until 1992 all EU member states were obliged to develop agri-environment programmes and since this time, AES are widely used. AES are often criticised for being ineffective and expensive. However, good results have been achieved with measures targeted on one bird species and used in projects advising farmers where and how to apply AES. Despite legitimate criticism, AES can help to slow down the declines of farmland bird populations, at least for a transitional period until sustainable agriculture has been established. This requires species-specific AES which are easy to implement and work well for the target species. In the German federal state of Saxony, such AES were developed and tested from 2009 to 2013 in a state-wide conservation project for ground-nesting farmland birds. Two of the studies with AES for the Skylark (study 1) and the Lapwing (study 2), which were part of scientific research, are presented here. For the Skylark, Skylark plots were tested at conventionally managed fields with winter cereals (n=10) or winter oilseed rape (n=10). Each field was divided in a test site with skylark plots and a control site without treatment. Skylark plots are unsown plots about 20 m² in size and applied in a density of about two plots per hectare. Further ten fields with winter cereals were in the same way equipped with additional tramlines that were not used for crop management. Both measures aimed to open the otherwise closed crop canopy to allow Skylarks to reach the ground and improve habitat conditions. Skylark territory mapping was carried out to reveal effects of the treatment. For the Lapwing, 61 lapwing plots were established within conventionally managed winter wheat and winter oilseed rape fields. These unsown fallow plots, mostly 1-2 ha in size, were created during autumn tillage and left bare until next summer. They were meant to provide a breeding site and a habitat for rearing the young. Lapwings and other bird species were mapped at the lapwing plots and nearby control sites. Factors influencing the success of the plots were modelled to obtain information on the design of a well-working AES. All three measures proved to be working well for the target species. At sites with skylark plots or additional tramlines, Skylark territory densities were about twice as high as at untreated control sites. The lapwing plots were also used about twice as likely as the untreated control sites. The hatching success was significantly higher, too. Particularly successful were large (>2 ha), sparsely vegetated lapwing plots at damp sites traditionally used for breeding. Other species also benefitted, especially from lapwing plots. The measures are therefore promising to provide positive effects on Skylark or Lapwing populations. They are relatively easy to implement and were repeatedly applied by the farmers involved in the project. Furthermore, synergy effects for other bird and plant species as well as for the biotope network can be expected by establishing lapwing plots at damp sites. The measures are suitable AES which, if widely adopted, have the potential to slow down, stabilise or even reverse the negative population trends. To promote these and to ensure their correct implementation, advise of farmers seems to be necessary, particularly for lapwing plots.
Bei vielen Agrarvögeln waren in den vergangenen Jahren starke Bestandsrückgänge zu verzeichnen, wobei mit Kiebitz (Vanellus vanellus) und Feldlerche (Alauda arvensis) zwei der ehemals häufigsten Arten am stärksten betroffen sind. Hauptursache hierfür ist die Intensivierung der Landwirtschaft. Eine mögliche Gegenstrategie sind nutzungsintegrierte Artenschutzmaßnahmen, mit denen versucht wird, die Belange des Artenschutzes eng in den landwirtschaftlichen Produktionsprozess einzubetten. Bedeutendstes Umsetzungsinstrument sind hierbei die EU-geförderten Agrarumweltmaßnahmen (AUM), die es seit 1992 in allen Mitgliedsstaaten gibt. Diese erwiesen sich in der Praxis jedoch oft als teuer und wenig erfolgreich. Vielversprechende Resultate wurden meist dann erzielt, wenn die Maßnahmen eng auf die Erfordernisse der Zielart(en) zugeschnitten waren und die Landwirte Beratung und Unterstützung bei der Umsetzung erhielten. Trotz aller Kritik an den AUM können diese zumindest für eine Übergangsphase auf dem Weg zu einer tatsächlich nachhaltigen Landwirtschaft helfen, die drastischen Bestandsrückgänge vieler Agrarvogelarten zu vermindern. Dazu werden aber zielartenspezifische und einfach umsetzbare Maßnahmen benötigt. Im sächsischen Bodenbrüterprojekt wurden von 2009 bis 2015 nutzungsintegrierte Artenschutzmaßnahmen entwickelt und erprobt. Zwei der projektbegleitenden wissenschaftlichen Studien zu AUM für Feldlerche (Studie 1) und Kiebitz (Studie 2) sind in der vorliegenden Arbeit zusammengefasst. Für die Feldlerche erfolgten Siedlungsdichteuntersuchungen auf konventionell bewirtschafteten Feldern mit Wintergetreide (n=10) oder Winterraps (n=10), die jeweils etwa zur Hälfte mit Feldlerchenfenstern bestellt waren, während der Restschlag als Vergleichsfläche diente. Zehn weitere Felder, ausschließlich in Wintergetreide, dienten in gleicher Weise der Erprobung der Anordnung zusätzlicher, für die Bewirtschaftung nicht benötigter Fahrgassen. Feldlerchenfenster sind ca. 20 m² große Saatlücken, die in einer Dichte von etwa zwei Fenstern je Hektar, ebenso wie die zusätzlichen Fahrgassen, die ansonsten dichten Kulturbestände öffnen und dadurch die Besiedlung durch die Zielart erleichtern. Für den Kiebitz wurden 61 Kiebitzinseln in konventionell bewirtschafteten Wintergetreide- und Winterrapsfeldern angelegt. Dies waren selbstbegrünte, meist 1-2 ha große Brachen, die bei der Herbstbestellung zwar bearbeitet, aber nicht gesät wurden. Im folgenden Frühjahr sollten die Flächen der Brut und Jungenaufzucht dienen. Die Untersuchungen beinhalteten Erfassungen der Zielart und weiterer Vogelarten auf den Kiebitzinseln und Vergleichsflächen sowie die statistische Modellierung verschiedener Faktoren für den Erfolg der Flächen. Im Ergebnis erwiesen sich alle drei Maßnahmen als erfolgreich. Auf Flächen mit Feldlerchenfenstern und zusätzlichen Fahrgassen war die Territoriendichte der Zielart etwa doppelt so hoch wie auf den Vergleichsflächen ohne Maßnahme. Die Kiebitzinseln wurden gleichfalls annähernd doppelt so oft von Kiebitzen besiedelt wie die Kontrollflächen. Der Schlupferfolg war signifikant höher. Besonders erfolgreich waren große (ca. >2 ha), spärlich bewachsene Kiebitzinseln an traditionell als Brutplatz genutzten Nassstellen. Insbesondere im Falle der Kiebitzinseln profitierten auch andere Arten. Die untersuchten Maßnahmen sind daher grundsätzlich geeignet, positive Effekte auf die Bestände von Feldlerche oder Kiebitz zu entfalten. Sie sind zudem vergleichsweise einfach umsetzbar und wurden von den am Projekt beteiligten Landwirten wiederholt realisiert. Mit der Anlage von Kiebitzinseln an Nassstellen lassen sich zudem Synergieeffekte für andere Tier- und Pflanzenarten sowie für den Biotopverbund erzielen. Die untersuchten Maßnahmen stellen damit geeignete AUM dar, die bei hinreichender Anwendung das Potenzial haben, die derzeit negativen Bestandstrends der Zielarten zu verlangsamen, zu stabilisieren oder sogar umzukehren. Zur Förderung der Umsetzung erscheint insbesondere im Fall der Kiebitzinseln eine fachliche Beratung der Landwirte unabdingbar.