Whinchat Saxicola Rubetra Research Articles

Environmental correlates of Whinchat Saxicola rubetra breeding territory retention in a declining upland population

ABSTRACT Capsule In a 461 km2 unenclosed upland landscape in south-west England, long-term breeding Whinchat Saxicola rubetra persistence is more likely in areas characterized by a mixture of Bracken Pteridium aquilinum, ericaceous vegetation, and very low tree densities, situated in steep-sided valleys at mid-altitudes, further from agriculturally improved grassland or arable. Aims To establish the correlates of Whinchat breeding territory retention between 1979 and 2015–2022 in a declining upland population. Methods Historical Whinchat territories (identified in 1979) were revisited to assess range occupancy, producing a lost (n = 104) and retained (n = 60) sample. Territory retention probability was modelled at local (100 × 100 m) and broad (500 × 500 m) scales against remotely sensed data and field habitat data measured in 2022. Results At the local scale, territory retention probability was greater in steeper valleys, further from arable or agriculturally improved grassland, peaked at five trees per ha in a quadratic response, and where Bracken cover was greater. Bracken cover effects were enhanced when ericaceous vegetation was also present. At the broad scale, retention probability was again greater in steeper valleys, with greater Bracken cover, and at very low tree densities in a quadratic response (but the latter was not important at the bottom of steep-sided valleys). Retention also peaked at around 350–400 m elevation in a quadratic response at the broad scale. Conclusions In this population in south-west England, steep-sided valleys at 350–400 m, with a light scattering of trees, situated further from intensive enclosed farmland are more likely to retain Whinchats long term. Within these areas, a mixed Bracken and ericaceous field-layer should be encouraged, and blanket afforestation avoided, although lower densities of native trees appear to be more tolerated.

Habitat and other environmental correlates of the decline of breeding Whinchats Saxicola rubetra in the UK since the mid-1990s

ABSTRACT Capsule Declines in Whinchat Saxicola rubetra breeding abundance in the UK vary with habitat and other environmental conditions. Aims To test for associations between changes in Whinchat abundance between 1994 and 2018 and measures of habitat and environmental conditions on UK breeding sites. Methods Whinchat counts collected through a national monitoring scheme were tested at coarse 1 km2 square and finer 200 m transect scales against habitat data collected in 2017/2018, plus remotely sensed data to test for long-term change. Results At the 1 km2 square scale, mean change in Whinchat abundance was more negative where woodland occurred more frequently, and at more northerly latitudes. Rates of decline were lower where there was greater cover of Purple Moor-grass Molinia caerulea and non-bracken vegetation height was taller. At the finer 200 m transect scale, more closely resembling Whinchat territory size, rates of decline were greatest in areas dominated by human sites, woodland, and enclosed farmland, compared to unenclosed open semi-natural habitats; however, within the latter category, declines were lower in grass-dominated relative to heather-dominated habitats. Rates of decline were also lower closer to valley bottoms, with greater Bracken Pteridium aquilinum cover and at mid-elevations (300 m), and greatest where there was greater cover of bare ground and trees, and moderate cover of grasses (excluding Molinia and Lolium spp.). The strength of the finer-scale associations varied between dominant habitat types. Whinchat abundance was lower where a remotely sensed index of vegetation productivity (normalized difference vegetation index [NDVI]) was higher, and abundance change more negative where temporal increases in NDVI were greater. Conclusion Unenclosed semi-natural grassland showed the lowest rate of decline and offers the best opportunities to conserve Whinchats. Woodland expansion is likely to have a detrimental impact on breeding Whinchats. Future research should investigate how important habitat and environmental correlates influence key demographic rates affecting recruitment.

Making virtual species less virtual by reverse engineering of spatiotemporal ecological models

AbstractThe virtual species (VS) and virtual ecologist (VE) approaches are useful tools that allow testing different methodological aspects of species distribution modelling. However, methods used to generate VS so far lack solutions that can ensure a high degree of biological realism, taking into account spatial and temporal variability of population densities.We have developed a method for generating dynamic VS that can reconstruct their living prototypes in a realistic way. The framework consists of fitting a spatiotemporal model to real abundance data, generating a VS population from that model over the entire study area and spanning the whole study period, calibrating the VS, and obtaining the VE data by sampling from the VS. The effectiveness of the developed approach has been illustrated by data from large‐scale and long‐term bird abundance monitoring, using the whinchatSaxicola rubetraas a study system. We evaluated how well the spatiotemporal model can reconstruct the ‘true’ system by comparing response curves and population trends between those used to generate the VS (i.e. what constitutes the ‘truth’) and those estimated from the replicated instances of VE data. In addition, we performed a sensitivity analysis to test how the varying sampling effort affects the accuracy of trend estimation.The synthetic VE data thoroughly reconstructed the real monitoring data. Response curves from generalized additive mixed models (GAMMs), fitted to these two types of data, showed high concordance, as indicated by the 95% confidence intervals of coverage probability of 87.7%–99.8% (mean 96.9%). The population trend estimated from the VE data accurately reconstructed the ‘true’ trend calculated from VS (coverage probability: 82.3%).The proposed method for generating VS and VE data by reverse engineering of the spatiotemporal ecological model reproduces well the properties of the original system, substantially increasing the ecological realism of simulation results. The method may have further applications in evaluating various modelling techniques used to study species range dynamics, where real‐world properties are of particular importance, like conservation and invasion biology or climate change impact assessment.

Early life conditions influence fledging success and subsequent local recruitment rates in a declining migratory songbird, the Whinchat Saxicola rubetra.

Life history traits and environmental conditions influence reproductive success in animals, and consequences of these can influence subsequent survival and recruitment into breeding populations. Understanding influences on demographic rates is required to determine the causes of decline. Migratory species experience spatially and temporally variable conditions across their annual cycle, making identifying where the factors influencing demographic rates operate challenging. Here, we use the Whinchat Saxicola rubetra as a model declining long-distance migrant bird. We analyse 10 years of data from 247 nesting attempts and 2519 post-fledging observations of 1193 uniquely marked nestlings to examine the influence of life history traits, habitat characteristics and weather on survival of young from the nestling stage to local recruitment into the natal population. We detected potential silver spoon effects where conditions during the breeding stage influence subsequent apparent local recruitment rates, with higher recruitment for fledglings from larger broods, and recruitment rate negatively related to rainfall that chicks experienced in-nest. Additionally, extreme temperatures experienced pre- and post-fledging increased fledging success and recruitment rate. However, we could not determine whether this was driven by temperature influencing mortality during the post-fledging period or later in the annual cycle. Brood size declined with hatching date. In-nest survival increased with brood size and was highest at local temperature extremes. Furthermore, nest survival was highest at nests surrounded with 40%-60% vegetation cover of Bracken Pteridium aquilinum within 50 m of the nest. Our results show that breeding phenology and environmental factors may influence fledging success and recruitment in songbird populations, with conditions experienced during the nestling stage influencing local recruitment rates in Whinchats (i.e. silver spoon effect). Recruitment rates are key drivers of songbird population dynamics. Our results help identify some of the likely breeding season mechanisms that could be important population drivers.

Niche segregation on the landscape scale of two co-existing related congeners in the sympatric zone – modelling approach

Co-occurence of related congeners is one of the most complicated ecological phenomena. Although such species are characterised by niche conservatism, which should exclude their stable co-existence, a communities often consist of sister species. Thus, there must be some ecological mechanism that separates them spatially or temporally. This study advocates that the answer is niche divergence that results from interspecific competition. Despite numerous studies documenting this biotic interaction as an important ecological process that segregates species spatially, only few deal with niche divergence between allotopy and syntopy in a mosaic of a large sympatric zone. That is why I decided to analyse the co-existence of two sister species, the Whinchat Saxicola rubetra and the Stonechat Saxicola rubicola in a sympatric zone, where both species occur alongside in syntopic sites, and separately in allotopic sites. Besides, I analyse the Whinchat's potential niche divergence between sympatric and allopatric zones which can be designated on the territory of Poland. It is assumed that niche divergence resulting from interspecific competition can be observed on the basis of differences in habitat preferences of one or both species between syntopy and allotopy, and also for the Whinchat between the sympatric and the allopatric zone. The assumptions were tested in generalised mixed-effect modelling and contrast analyses based on a large dataset of bird density in Poland. Both species demonstrated shifted environmental preferences between syntopy and allotopy, while in allopatry both species had similar niche preferences. The Whinchat also indicated no differences between allopatry and allotopy. Thus, the adopted analytical system clearly proves that the co-existence of congeneric species is possible due to niche divergence, which most likely results from interspecific competition.

No evidence that declining Whinchat Saxicola rubetra are currently limited by the availability of apparently suitable breeding habitat within the UK uplands

No evidence that declining Whinchat Saxicola rubetra are currently limited by the availability of apparently suitable breeding habitat within the UK uplands

Upward elevational shift by breeding Whinchat Saxicola rubetra in response to cessation of grazing in upland grassland

ABSTRACT Capsule The distribution of breeding Whinchats Saxicola rubetra shifted uphill following the cessation of grazing, potentially compromising their breeding success through additional squeezing of suitable habitat and environmental niches. Aims To assess whether breeding territories occupied by a conservation-priority grassland bird followed changes in sward structure associated with environmental exposure following cessation of grazing. Methods Whinchat territories and breeding success were monitored at upland study sites in Scotland during a period of habitat transformation from livestock-grazed grassland to young woodland with herbivores excluded. Results After grazing was excluded, there was generally an upwards elevational shift of breeding attempts by Whinchats (by 43 m in 7 years at one site). While the study sites were grazed, breeding attempts were more successful at lower elevations. After grazing ceased, there was lower breeding success at lower elevations where the resulting taller, denser vegetation likely restricted available foraging habitat. Despite that, lower areas continued to be occupied by territorial Whinchats. Conclusions The conservation of grassland birds within afforestation schemes could be supported by the maintenance of some open habitats at suitable elevations. However wider conservation of grassland birds, including within forested and pastoral high nature value farmed landscapes would benefit from a better understanding of the mechanisms operating on breeding success and habitat choice within these dynamically changing habitats.

Grassland bird species in mountain pastures Zaprikraj and Zapleč in the southern Julian Alps, Slovenia

AbstractGrassland birds were surveyed in two mountain pastures (Zaprikraj and Zapleč) in the southern part of the Julian Alps, Slovenia. The survey was carried out during the mornings between 26 and 30 June 2005. Due to the incomplete survey (only one visit, no nocturnal or targeted surveys and late season survey), the surveyed birds’ breeding density is only a rough estimate. 167 pairs belonging to 12 species were counted, with Tree (average density of 1.64 p/10 ha) and Water Pipit (average density of 1.60 p / 10 ha) being the most abundant. Both were observed in all altitudinal belts. The highest density in individual altitudinal belt was calculated for Red-backed ShrikeLanius collurio(3.78 p/10 ha) and Water Pipit (3.61 p/10 ha). In well preserved grasslands in the study area, most species reached high breeding densities compared to other parts of Slovenia and all were recorded higher than during the 1992 survey, although still mostly within limits of the elevations elsewhere in Slovenia. Breeding density of SkylarkAlauda arvensisdecreased with the elevation. WhinchatSaxicola rubetra, Skylark and Red-backed Shrike used significantly gentler slopes, while Pipits showed no preference for particular slopes.

Whinchat survival estimates across Europe: can excessive adult mortality explain population declines?

AbstractEuropean farmland birds show massive large‐scale population declines due to agricultural intensification. Long‐distance migrants are particularly affected as their populations appear to undergo larger declines than those of residents and short‐distance migrants, raising the question about the impact of non‐breeding environmental conditions and their potential impact on annual survival. The whinchatSaxicola rubetra,an Afro‐Palaearctic migrant inhabiting open habitats, has strongly declined over the last decades. Most of the conservation effort for this species has focused on improving the breeding success in Europe, but it remains unclear whether habitat changes in non‐breeding areas may also have contributed to the population declines through a decrease in adult survival. We studied survival of whinchats from eight breeding populations across Europe by analysing capture–recapture data. We found that apparent survival was consistently higher in males than in females and higher in successful than in failed breeders independently of the sex. True adult survival may, however, hardly differ between sexes being about 0.5 and 0.6 and a simple population model suggests true juvenile survival to be between 0.2 and 0.35. Adult survival was unrelated to population trends suggesting that the main demographic problem of the whinchats is likely insufficient reproduction, a feature that is shared with other declining grassland specialists. Finally, in line with results on other migratory farmland species, our study suggests that conservation activities for whinchats should in first place focus on Europe.

Evidence for senescence in survival but not in reproduction in a short-lived passerine.

Senescence has been studied since a long time by theoreticians in ecology and evolution, but empirical support in natural population has only recently been accumulating. One of the current challenges is the investigation of senescence of multiple fitness components and the study of differences between sexes. Until now, studies have been more frequently conducted on females than on males and rather in long‐lived than in short‐lived species. To reach a more fundamental understanding of the evolution of senescence, it is critical to investigate age‐specific survival and reproduction performance in both sexes and in a large range of species with contrasting life histories. In this study, we present results on patterns of age‐specific and sex‐specific variation in survival and reproduction in the whinchat Saxicola rubetra, a short‐lived passerine. We compiled individual‐based long‐term datasets from seven populations that were jointly analyzed within a Bayesian modeling framework. We found evidence for senescence in survival with a continuous decline after the age of 1 year, but no evidence of reproductive senescence. Furthermore, we found no clear evidence for sex effects on these patterns. We discuss these results in light of previous studies documenting senescence in short‐lived birds. We note that most of them have been conducted in populations breeding in nest boxes, and we question the potential effect of the nest boxes on the shape of age‐reproductive trajectories.

Weak migratory connectivity, loop migration and multiple non‐breeding site use in British breeding Whinchats Saxicola rubetra

Determining the links between breeding populations and the pressures, threats and conditions they experience presents a challenge for the conservation of migratory birds which can use multiple sites separated by hundreds to thousands of kilometres. Furthermore, migratory connectivity – the connections made by migrating individuals between networks of breeding and non‐breeding sites – has important implications for population dynamics. The Whinchat Saxicola rubetra is declining across its range, and tracking data from a single African non‐breeding site implies high migratory spread. We used geolocators to describe the migration routes and non‐breeding areas of 20 Whinchats from three British breeding populations. As expected, migratory spread was high, with birds from the three populations overlapping across a wide area of West Africa. On average, in non‐breeding areas, British breeding Whinchats were located 652 km apart from one another, with some likely to share non‐breeding areas with individuals from breeding populations as far east as Russia. Four males made a direct non‐breeding season movement to a second, more westerly, non‐breeding location in January. Autumn migration was through Iberia and around the western edge of the Sahara Desert, whereas spring migration was more direct, indicating an anticlockwise loop migration. Weak migratory connectivity implies that Whinchat populations are somewhat buffered against local changes in non‐breeding conditions. If non‐breeding season processes have played a role in the species’ decline, then large‐scale drivers are likely to be the cause, although processes operating on migration, or interactions between breeding and non‐breeding processes, cannot be ruled out.

Low first-year apparent survival of passerines in abandoned fields in northwestern Russia

Abstract First-year survival probability of migratory passerines during the period between fledging and first reproduction is a highly variable parameter that has a major effect on population dynamics. We used a long-term mark–recapture dataset (2002–2018) to examine first-year survival of 3 passerine species breeding in abandoned agricultural fields of northwestern Russia: Booted Warbler (Iduna caligata), Whinchat (Saxicola rubetra), and Western Yellow Wagtail (Motacilla flava). We banded 3,457 nestlings, including 1,363 Booted Warblers, 1,699 Whinchats, and 395 Western Yellow Wagtails, and resighted 12 Booted Warblers, 29 Whinchats, and 13 Western Yellow Wagtails in the year after fledging. We evaluated first-year apparent survival rates using Cormack-Jolly-Seber models in MARK program within the multispecies approach. We tested effect of fledge date on the first-year apparent survival. In all focal species, first-year apparent survival rates were low and reached the lower limits known for migratory passerines. We found no differences in first-year survival rates among the 3 species: the estimated average first-year apparent survival rate of all species was 0.05 ± 0.01. The fledge date had a considerable impact on first-year survival rate: later fledge dates negatively affected first-year survival. We suggest that first-year apparent survival rates in our study were low due to low natal philopatry and high mortality in the post-fledging period. Low apparent first-year survival may be a specific feature of open-nesting birds breeding in abandoned fields that are low-quality habitats because of high predation pressure.

Mowing is the greatest threat to Whinchat Saxicola rubetra nests even when compared to several natural induced threats

Birds in agroecosystems are among the most threatened in Europe, largely due to intensification of agricultural production. For the Whinchat (Saxicola rubetra), an indicator species of high nature value grasslands, and whose population is decreasing over most of Europe, mowing was reported as the most significant threat several times. However, no studies to date compare mowing to other potentially significant threats to confirm this. We investigated mowing and four additional nature-related threats simultaneously and used them to construct a set of models to explain which factor has the most significant impact on Whinchat nest survival. Our study was done on a type of a grassland often found in protected areas with moderately improved production, where the density of Whinchat is high, yet influenced by human activities and natural factors. Date of mowing explained nest failure the best, followed by predation and weather, confirming mowing as the most significant problem to nest survival. Changes in mowing regime were identified as an important conservation measure. To increase breeding success of grassland birds, some of these measures (e.g., mowing postponement) were already suggested and used in EU through Agri-Environmental measures (AEM) program, but with little effect. We believe this is due to the little known indirect effects of mowing on birds during the post-fledging and pre-migration period, which is one of the least understood parts of their life cycle.

Light stalks increase the precision and accuracy of non-breeding locations calculated from geolocator tags: a field test from a long-distance migrant

ABSTRACTCapsule: There is a substantial gain in precision and accuracy of geolocator locations when using a light stalk.Aims: Light stalks or tubes increase the accuracy of geolocators when tracking migrant birds because they reduce potential shading of the light sensor by feathers but may increase detrimental tag effects. We aimed to determine how adding light stalks to geolocator tags increased accuracy and precision of locations.Methods: We quantified how precision and accuracy of geolocator locations was affected by comparing variation of sunrise and sunset times from tags with variable length light stalks (6 of 0 mm, 8 of 5 mm and 21 of 10 mm). Tags were fitted to Whinchats Saxicola rubetra in central Nigeria (the known location to compare accuracy), and variance in latitude and longitude of geolocator estimated locations were also compared across light stalk lengths during spring migration stationary locations, and at breeding sites in Eastern Europe, for both Geolight and FlightR methods.Results: Without a light stalk, the standard deviation of sunset and sunrise times increased by 50% and 100%, respectively (i.e. less precise): confidence intervals for latitude were larger by about 4.3 degrees at non-breeding low latitudes and 1.8 degrees at stop-over latitudes, or confidence intervals for longitude were larger by 2.3 degrees, dependent on analysis method. Estimated sun elevation angles were significantly less accurate and so calculated non-breeding locations were significantly less accurate by about 8 degrees of latitude. Precision in sunrise, sunset times, latitude and longitude, was similar when using a 5 mm or 10 mm stalk.Conclusions: The results show a substantial gain in precision and accuracy of low latitude geolocator locations when using a light stalk that brings the sensor above covering feathers. There is no advantage from longer light stalk lengths than those necessary to just expose the light sensor above the feathers, at least for small passerines.

Breeding bird assemblages supported by developing upland shrub woodland are influenced by microclimate and habitat structure

ABSTRACTCapsule: Local micro-climate, as well as habitat, influences the abundance of birds within dynamically changing upland habitats.Aims: To identify the relative importance of near-ground temperature (as an index of climate at a scale typical of the territory of breeding passerines) and habitat for some breeding birds in upland Scotland where land uses and habitats are changing.Methods: Timed point counts sampled breeding birds within the marginal uplands of Scotland in habitats at successional stages between pasture and shrubland. Habitat composition and ambient temperatures were recorded at the same sampling points. Generalized linear mixed models were used to assess associations of bird abundance, species richness and species diversity with habitat and ambient near-ground temperature.Results: Species richness increased with mean temperature, was greatest within areas of shrubland and was lowest in open habitats. Different species showed individual associations with temperature and habitat. Species predominantly associated with shrubland tended to have a negative association with temperature.Conclusions: Understanding the habitat and climatic niche requirements of different species will facilitate appropriate land management to be targeted within appropriate climatic patches. For example, open habitats suitable for Whinchats Saxicola rubetra should be within warmer climate patches (typically lower elevation or southern aspects) while shrublands can support Willow Warblers Phylloscopus trochilus at cooler elevations and aspects. Management that delivers a mosaic of habitats, spanning areas of climatic heterogeneity should enhance the diversity of birds supported in the upland margins and potentially their resilience to changing environmental conditions.

Could Meadow Passerine Distribution Within a Grassland System be Influenced by Spatial Variation in the Mowing Schedule?

This study explored meadow passerine capacity to select habitat conditions likely to preserve their breeding success. We observed the variation in bird abundance, assessed with the point count method, over a 25-year period (1993–2017) within two phytosociological facies of the hay-meadows in the lower Saone Valley (3.000 ha), eastern France: a meso-hygrophilic facies characterized by increasingly early mowing, and a hygrophilic facies mown later, with thereby a lower risk of nesting failure. At the beginning of the monitoring (1993–2001), birds were evenly distributed within the two facies. Later on, as more than 90% of meso-hygrophilic meadows were already mown by July 1, birds became more abundant in the hygrophilic facies. This trend was observed in each of the two most abundant species, the Whinchat Saxicola rubetra and the Corn Bunting Emberiza calandra. In two hygrophilic areas (55 and 76 ha) and two meso-hygrophilic areas (49 and 116 ha), passerine territories were mapped in 2011 with the territory mapping method and invertebrates were captured weekly on transects with colour plates and Barber traps. In spite of substantially higher invertebrate abundance, passerine territory density was lower in meso-hygrophilic study sites (6.4 territories/ 10 ha vs. 10.6). Within each study site however, captured invertebrates were more abundant in the areas selected by territorial birds. In fact, bird abundance estimated from point counts in 2011 varied negatively with the percentage mown by July 1 within a 200m-radius in 2010. This apparently adaptive behaviour leading to a selection of later mown fields seemed to be successful since bird abundance increased until 2010. However, after a succession of extreme climatic events (droughts, late floods), passerine abundance declined thereafter in both facies.

Trends and synchrony in fluctuations of the numbers of Whinchat (Saxicola rubetra) and European Stonechat (S. rubicola) in chalk steppe of North-eastern Ukraine

The problem of coexistence of related species within the same communities poses a question of how similar are the fluctuations of their numbers. Whinchat (Saxicola rubetra) and European Stonechat (S. rubicola) is an example of such a pair of phylogenetically related bird species, which are members of a foraging guild of sit-and-wait insectivores in open habitats. In Ukraine both species are quite common in meadows, steppes, fallow lands and other grassland habitats including undisturbed areas in nature reserves. In North-eastern Ukraine Whinchat and European Stonechat are characteristic of the bird communities of hills with chalk outcrops where they represent a group of species linked to chalk steppe. The trends in numbers and synchrony in fluctuations in the numbers of both species in this habitat were studied in national nature park ‘Dvorichanskyi’, Kharkiv region, North-eastern Ukraine for 9 years’ period (2010–2018). The data were retrieved from the results of yearly monitoring bird counts in chalk grassland habitats. The total-area census method was used on 3 plots of unequal size (17.8, 33.2, and 41.0 ha). The trends were analysed in programme TRIM (TRends & Indices for Monitoring data) vers. 3.53. The extent of synchrony was estimated by means of zero-lag cross-correlation between the time series of log-transformed growth rates. Additionally, the coincidence of the direction of changes and the coincidence of peaks in series were checked. The trend in Whinchat abundance is characterised as significant steep decline (multiplicative slope 0.840, standard error 0.03; p<0.01). The trend in European Stonechat abundance is classified as non-significant uncertain (multiplicative slope 0.909, standard error 0.06). The trends in both species correspond to general trends in Europe evidenced in PanEuropean Common Bird Monitoring Scheme for 1980–2016 and 1989–2016 for Whinchat and European Stonechat accordingly. The synchrony in fluctuations of the numbers of Whinchat and European Stonechat in chalk steppe habitats proved to be weak. Time series of both species abundances run in different directions almost in all cases where the comparison was possible that indicates probable differences in the causes of the dynamics of their populations. The study prompts to launch new or extend existing monitoring schemes in nature reserves and national parks in Ukraine to get reliable estimates for the trends in numbers of both rare and common bird species.

Energy crops affecting farmland birds in Central Europe: insights from a miscanthus-dominated landscape

The expansion of energy crops such as miscanthus Miscanthus x giganteus has changed the habitat of European farmland birds. However, most studies on the subject are based in Western Europe. We surveyed the avian community in a sample bioenergy landscape in Poland to investigate the pattern of use of the crop by birds in Central Europe. During a year-long survey, 80 species were noted, with 32 sighted in miscanthus. The number of bird sightings was negatively correlated with the area covered by miscanthus in study plots. In contrast to results from Western Europe, most woodland-generalist bird species tended to avoid miscanthus. Farmland species (e.g. the corn bunting Miliaria calandra; the tree sparrow Passer montanus; the starling Sturnus vulgaris; the yellowhammer Emberiza citrinella) were less frequently sighted in the crop than in other habitats. Only a few species were sighted more often in miscanthus than in other habitats, e.g. the marsh warbler Acrocephalus palustris; the reed bunting Emberiza schoeniclus; the whinchat Saxicola rubetra. The potential impact of expanded miscanthus cropping on bird communities in Central and Eastern Europe may diverge from predictions derived from studies based in Western Europe due to differing habitat preferences and bird densities between the regions. For a majority of farmland species, the crop may constitute only a suboptimal, supplementary habitat, with only a few birds potentially adapting to the exploitation of bioenergy plantations.

Simulated Rainfall Reduces the Insulative Properties of Bird Nests

Bird nests are variable in design but all are constructed for the purpose of incubation. The potentially onerous energetic costs of incubation have meant that previous studies have focussed on thermal insulation but nests are often exposed to a variety of environmental factors, including rainfall. Those few studies that have investigated the effects of water on nests have saturated the walls by soaking but this may not reflect what a nest would typically encounter in situ during rainfall. Here, nests of four species of songbird (Common Chaffinch Fringilla coelebs, Common Linnets Linaria cannabina, Meadow Pipits Anthus pratensis, and Whinchats Saxicola rubetra) were investigated using temperature loggers to determine the effect of simulated rainfall on nest wall insulation. Simulated rainfall, produced by water dripping through a coffee percolator, significantly reduced the insulatory values of nests, and significantly increased the rate of cooling of temperature loggers inside the nest cup. No significant effect of species, or nest mass, was observed. Even when wet nest walls provided some insulation but whether this is attributable to the nest materials chosen by each species was not clear. The nest site chosen by the birds may also offer considerable protection from the weather. Further research is needed to better understand how rainfall affects the insulative properties of nests in situ.

Nest monitoring does not affect nesting success of Whinchats Saxicola rubetra

It is important to assess the effect that research activities may have on animals in the wild, especially when key parameters, such as breeding success, could potentially be influenced by observer activity. For birds, some studies have suggested that nest monitoring can increase the chances of nest failure due to predation, whereas others suggest that human nest visits may actually deter mammalian predators. Nest monitoring visits can also influence breeding success more indirectly by altering parental provisioning behaviour. Here, the influence of monitoring activities on nest success was examined in a ground‐nesting grassland bird, the Whinchat Saxicola rubetra. During the egg phase, a sample of nests were not visited between the initial finding event and the estimated hatching date; instead, the nest status was assessed at a distance. Daily survival rates (DSR) for these nests were compared with that of nests visited every 2 days. During the nestling phase, the effects of observer nest visits on parental provisioning behaviour were determined. Nest visits were found not to affect egg DSR significantly, and parental provisioning was disrupted for a maximum of 20 min (0.52% of the nestling period) following an observer visit. Given the variation in response to nest visits across species, we suggest that consideration should be given to observer impact in all studies where predation risk is high. Here, we illustrate a method for researchers to assess the impact of their nest visits to ensure they are not biasing estimates of breeding success.