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1. How demographic factors lead to variation or change in growth rates can be investigated using life table response experiments (LTRE) based on structured population models. Traditionally, LTREs focused on decomposing the asymptotic growth rate, but more recently decompositions of annual ‘realized’ growth rates have gained in popularity.2. Realized LTREs have been used particularly to understand how variation in vital rates translate into variation in growth for populations under long-term study. For these, complete population models may be constructed by combining data in an integrated population model (IPM). IPMs are also used to investigate how temporal variation in environmental drivers affect vital rates. Such investigations have usually come down to estimating covariate coefficients for the effects of environmental variables on vital rates, but formal ways of assessing how they lead to variation in growth rates have been lacking.3. We extend realized LTREs in two ways. First, we further partition the contributions from vital rates into contributions from temporally varying factors that affect them. The decomposition allows us to compare the resultant effect on the growth rate of different environmental factors that may each act via multiple vital rates. Second, we show how realized growth rates can be decomposed into separate components from environmental and demographic stochasticity. The latter is typically omitted in LTRE analyses.4. We illustrate how to use the approach in an IPM for data from a 26 year study on northern wheatears (Oenanthe oenanthe), a migratory passerine bird breeding in an agricultural landscape. For this population, consisting of around 50-120 breeding pairs per year, we partition variation in realized growth rates into environmental contributions from temperature, rainfall, population density, and unexplained random variation via multiple vital rates, and from demographic stochasticity.5. The case study suggest that variation in first year survival via the random component, and adult survival via temperature are two main factors behind environmental variation in growth rates. More than half of the variation in growth rates is suggested to come from demographic stochasticity, demonstrating the importance of this factor for populations of moderate size.

Wetlands are biodiversity hotspots that provide several essential ecosystem services. On a global scale, wetlands have greatly declined due to human activities. To counteract wetland loss, created wetlands are used as a conservation tool to facilitate biodiversity and provide habitats mainly for birds and amphibians. Fishes are likely to colonise the created wetlands and potentially affect the diversity and occurrence of amphibians. Still, species occurrence data for fish in created wetlands are largely lacking. Using eDNA metabarcoding, we investigated occurrence and co-occurrence patterns of fish and amphibian communities in 52 wetlands (some of which are ponds) created to benefit mainly bird and amphibian communities in south-central Sweden. Altogether, 17 fish and five amphibian species were detected in the created wetlands out of the 32 fish and six amphibian species found in the regional species pool. Amphibians were less common in wetlands physically connected to other wetlands. Connected wetlands were more fish-rich than isolated ones, suggesting potential fish avoidance. Additionally, the amphibian community occupied a narrower environmental niche compared to the fish community. Nevertheless, we observed only five statistically significant negative fish-amphibian species co-occurrences (out of 14 species considered). Even though our results suggest amphibian avoidance/exclusion from the created biodiversity wetlands, they also show that fish and amphibians frequently co-exist. Increased habitat heterogeneity in terms of water vegetation, size, shape, and structure of the wetland could be possible factors enabling the co-existence of these two taxa. With this study, we contribute to the general knowledge of fish occurrence patterns in created biodiversity wetlands. By comparing the frequencies of fish occurrence in natural and created wetlands, we have shown that there was some mismatch in what is common in natural compared to created wetlands. This mismatch probably comes from species-specific habitat requirements, stocking, and differences in detectability when using eDNA metabarcoding (small species detected) versus conventional multi-mesh gill-net methods (small species missed). Therefore, our results obtained using eDNA metabarcoding can complement the pre-existing knowledge of amphibian and fish associations and increase our understanding of how to create wetlands to facilitate biodiversity of several taxa.

1. Estimating the contribution of demographic parameters to changes in population growth is essential for understanding why populations fluctuate. Integrated population models (IPMs) offer a possibility to estimate the contributions of additional demographic parameters, for which no data have been explicitly collected— typically immigration. Such parameters are often subsequently highlighted as important drivers of population growth. Yet, accuracy in estimating their temporal variation, and consequently their contribution to changes in population growth rate, has not been investigated. 2. To quantify the magnitude and cause of potential biases when estimating the contribution of immigration using IPMs, we simulated data (using northern wheatear Oenanthe oenanthe population estimates) from controlled scenarios to examine potential biases and how they depend on IPM parameterization, formulation of priors, the level of temporal variation in immigration and sample size. We also used empirical data on populations with known rates of immigration: Soay sheep Ovis aries and Mauritius kestrel Falco punctatus with zero immigration and grey wolf Canis lupus in Scandinavia with near-zero immigration. 3. IPMs strongly overestimated the contribution of immigration to changes in population growth in scenarios when immigration was simulated with zero temporal variation (proportion of variance attributed to immigration = 63% for the more constrained formulation and real sample size) and in the wild populations, where the true number of immigrants was zero or near-zero (kestrel 19.1%–98.2%, sheep 4.2%– 36.1% and wolf 84.0%–99.2%). Although the estimation of the contribution of immigration in the simulation study became more accurate with increasing temporal variation and sample size, it was often not possible to distinguish between an accurate estimation from data with high temporal variation versus an overestimation from data with low temporal variation. Unrealistically, large sample sizes may be required to estimate the contribution of immigration well. 4. To minimize the risk of overestimating the contribution of immigration (or any additional parameter) in IPMs, we recommend to: (a) look for evidence of variation in immigration before investigating its contribution to population growth, (b) simulate and model data for comparison to the real data and (c) use explicit data on immigration when possible.

Los autores de la UAM pertenecen al Terrestrial Ecology Group (TEG), Agricultural intensification is one of the main drivers of species loss worldwide, but there is still a lack of information about its effect on functional diversity of arable weed communities. Using a large-scale pan European study including 786 fields within 261 farms from eight countries, we analysed differences in the taxonomic and functional diversity of arable weeds assemblages across different levels of agricultural intensification. We estimated weed species frequency in each field, and collected species' traits (vegetative height, SLA and seed mass) from the TRY plant trait database. With this information, we estimated taxonomic (species richness), functional composition (community weighted means) and functional diversity (functional richness, evenness, divergence and redundancy). We used indicators of agricultural management intensity at the individual field scale (e.g. yield, inputs of nitrogen fertilizer and herbicides, frequency of mechanical weed control practices) and at the landscape scale surrounding the field (i.e. number of crop types, mean field size and proportion of arable land cover within a radius of 500 m from the sampling points). The effects of agricultural intensification on species and functional richness at the field scale were stronger than those of intensification at the landscape scale, and we did not observe evidence of interacting effects between the two scales. Overall, assemblages in more intensified areas had fewer species, a higher prevalence of species with ruderal strategies (low stature, high leaf area, light seeds), and lower functional redundancy. Maintaining the diversity of Europe's arable weed communities requires some simple management interventions, for example, reducing the high intensity of field-level agricultural management across Europe, which could be complemented by interventions that increase landscape complexity. A free Plain Language Summary can be found within the Supporting Information of this article

Despite large conservation efforts to halt the loss of farmland biodiversity in Europe, negative population trends are still observed, especially for common species. Old villages and human settlements are biodiversity hotspots and important breeding habitats for farmland birds, but recent requirements for energy saving measures and improved living comfort have changed their architecture and habitats. Consequently, modernization of villages may negatively affect bird diversity due to the loss of nesting and foraging sites. We investigated how the abundance and diversity of birds breeding in 104 Polish villages varied in relation to the degree of modernization as estimated by the proportion of new and renovated homesteads. Abundance of building-nesting species, but not tree-nesting species, declined by 50% across a gradient of old to highly modernized villages. The contribution of new versus renovated houses to the observed decline was similar. Synthesis and applications. Rural modernization may have a dramatic effect on abundance of birds nesting on buildings, thus may be an important and overlooked contributor to farmland bird population declines in Europe. Villages and rural properties fall outside of current conservation policy as they are neither protected areas nor agricultural lands (where agri-environmental schemes can be applied). The observed conflict between sustainability goals such as increased building energy efficiency and biodiversity conservation suggests that sustainable rural development should better link modernization with conservation measures, for example, by constructing nesting sites when renovating and building new houses. The challenge is to design modern buildings that are both energy-efficient and biodiversity-friendly to generally improve quality of life for rural communities and to halt or reduce farmland bird declines in rural landscapes. Designers and architects can find inspiration from traditional architecture and add a variety of nest-box types.

Adaptive management (AM) is widely promoted to improve management of natural resources, yet its implementation is challenging. We show that obstacles to the im- plementation of AM are related not only to the AM process per se but also to external factors such as ecosystem properties and governance systems. To overcome ob- stacles, there is a need to build capacities within the AM process by ensuring ade- quate resources, management tools, collaboration, and learning. Additionally, building capacities in the legal and institutional frames can enable the necessary flexibility in the governance system. Furthermore, in systems experiencing profound changes in wildlife populations, building such capacities may be even more critical as more flexibility will be needed to cope with increased uncertainty and changed environmental conditions.

Funding: The Swedish Bird Survey was supported by grants from the Swedish Environmental Protection Agency, with additional financial and logistic support from the Regional County Boards (Länsstyrelsen). The surveys were carried out within the framework of the strategic research environment Biodiversity and Ecosystem Services in a Changing Climate (BECC). The Norwegian breeding bird monitoring (Norsk hekkefuglovervåking) was financed by the Norwegian Environment Agency and the Ministry of Climate and Environment. Our research was funded through the 2017-2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND programme with financial support from the Research Council of Norway (295767), the Swedish Research Council FORMAS (2018-02440, 2018-02441), the Academy of Finland (323527, 326327, 326338) and the U.S. National Science Foundation (ICER-1927646). The relationships between species abundance or occurrence versus spatial variation in climate are commonly used in species distribution models (SDMs) to forecast future distributions. Under "space-for-time-substitution", the effects of climate variation on species are assumed to be equivalent in both space and time. Two unresolved issues of space-for-time-substitution are the time period for species' responses and also the relative contributions of rapid- versus slow reactions in shaping spatial and temporal responses to climate change. To test the assumption of equivalence, we used a new approach of climate decomposition to separate variation in temperature and precipitation in Fennoscandia into spatial, temporal and spatio-temporal components over a 23-year period (1996-2018). We compiled information on land cover, topography and six components of climate for 1756 fixed route surveys and we modelled annual counts of 39 bird species breeding in the mountains of Fennoscandia. Local abundance of breeding birds was associated with the spatial components of climate as expected, but the temporal and spatio-temporal climatic variation from the current and previous breeding seasons were also important. The directions of the effects of the three climate components differed within and among species, suggesting that species can respond both rapidly and slowly to climate variation and that the responses represent different ecological processes. Thus, the assumption of equivalent species' response to spatial and temporal variation in climate was seldom met in our study system. Consequently, for the majority of our species, space-for-time substitution may only be applicable once the slow species' responses to a changing climate have occurred. Whereas forecasts for the near future need to accommodate the temporal components of climate variation. However, appropriate forecast horizons for space-for-time substitution are rarely considered and may be difficult to reliably identify. Accurately predicting change is challenging because multiple ecological processes affect species distributions at different temporal scales. Publisher PDF

Restoring wetlands to improve habitats for birds has become an important conservation tool as many wetlands have deteriorated and wetland bird populations declined. To what extent such restorations are effective is not well known because surveys usually either lack data before the restoration or means of correcting for background population trends. We identified wetland restorations made in agricultural landscapes in Sweden and retrieved all available Before-After survey data of breeding birds. From the resulting heterogeneous surveys, we quantified the effectiveness of restorations for eight bird groups comprising 72 bird species from 30 wetlands. We used national survey data to correct for background population trends. We estimated that island breeder populations have increased by between 62 % and 315 % (95 % confidence intervals) following restorations. Deep water foragers, shallow water foragers and short meadow breeders also mainly increased following restoration. The direction of effect was uncertain for tall meadow breeders, reed breeders and predators. Shrubland breeder populations declined between-55 % and-4 % following restorations. While restoration measures seemed to generally benefit about half of the breeding wetland bird community, estimated species-and site-specific re-sponses varied greatly and were associated with large uncertainty. Such heterogeneity in responses can arise due to biotic and abiotic interactions, varying management actions and survey methods between wetlands. Thus, to improve the effectiveness of future wetland restorations, funding bodies and environmental agencies should require standardised Before-After bird surveys at both restored and non-restored reference sites. Such improved survey designs would facilitate the development of more efficient restoration efforts.

The aim of this study is to compare policy schemes for ecological compensation applied at national and regional levels, using exploited inland wetlands as an example. We study whether uncertainty, due to natural variability and measurement difficulties, motivates compensation that is carried out in the same region as that of the exploited site, or whether it rather motivates nationwide compensation schemes. For this purpose, we develop an empirical, chance-constrained programming model of cost-effective wetland management. The model is spatially differentiated and accounts for heterogeneity in wetland quality across wetland types and regions. Wetland quality is defined by three alternative biodiversity indices: species richness, population-weighted species richness, and red-listed species richness, estimated from voluntarily reported data on breeding bird species observations. Results show that regional schemes are more expensive, in particular if the policy maker dislikes uncertainty and wants to prioritize uncommon species. Contrary to expectations from the theoretical analysis, regional schemes would lead to a higher risk-adjusted level of biodiversity at the national level. However, regionalization also implies that targets cannot be achieved if a high safety margin is imposed. Trading ratios are robust to the choice of wetland quality index.

The central tenet of European farmland ecology is that agricultural intensification during the 20th century was largely responsible for dramatic declines in species abundances. However, during this time, human rural settlements were also undergoing radical changes through modernization, with undocumented biodiversity impacts in this important wildlife habitat. We performed the first ever large‐scale study to disentangle the impact of these simultaneous processes on farmland bird diversity in 104 Polish villages. We show that modernized villages and their surrounding agricultural fields had 50–60% fewer birds than those in and around comparable older villages. The relative contribution of modernization versus agricultural intensification to predicted bird declines was 88% versus 12% for bird communities in villages and 56% versus 44% in surrounding croplands, with considerable variation among ecological species subgroups. These results challenge our current understanding of agricultural ecosystem ecology and how best to implement conservation measures costing billions of euros annually.

An important function of agri-environmental schemes (AES) is to change management of pastures to better conserve biodiversity. However, the effects of most AES on biodiversity are poorly understood, especially when it comes to effects of AES management over time. The main aim of this study is to investigate if the species richness and abundance of grassland specialists of vascular plants and two important insect pollinator groups (bumblebees and butterflies) differ over time (5 years) in pastures with AES management (two value levels; general values and special values) and pastures without AES management. We also investigate if local vegetation characteristics and landscape composition relate to species richness in semi-natural grasslands. Using data from more than 400 sites we found that species richness of vascular plants (grassland specialists) was higher in pastures with AES management (for special and general values) compared to those without AES, which implies that these schemes do have value of the conservation of plant diversity. However, species richness and abundance of butterflies (grassland specialists) and bumblebees (all species) did not differ significantly among the three AES categories. We found no evidence that the type of AES management caused any changes in species richness of plants, butterflies or bumblebees during the 5 year period of our investigation. It appears that AES management that encourages uniform and minimum levels of grazing can have both positive and negative effects on biodiversity. For example, pollinators may benefit from a lower grazing intensity that could increase flower richness and heterogeneity in vegetation height. However, low grazing intensity may lead to increased cover of trees and shrubs, which can have negative effects for both insect pollinators and vascular plants. The effects of landscape composition were weak and only species richness of bumble bees were associated with landscape composition. Designing management regimes to maintain suitably heterogeneous vegetation layer, and continued long-term monitoring of biodiversity will be critical for safeguarding culturally and functionally important semi-natural grasslands.

The effect that extreme natural events have on biological diversity is relatively poorly known. We used a before–after control-impact (BACI) design to analyze changes in bird abundances and communities following Hurricane Gudrun, which struck southern Sweden in January 2005, felling 75 million m3 of forest and causing damage to 5% of forested areas (half a million hectares) in a few hours. We used recent measures of impact in combination with classical BACI contrasts to analyze bird count data from a monitoring program in Sweden. We investigated changes in the abundance of 17 species commonly found in forests, along with changes in species composition and functional structure of the bird community. In total, we considered 34 response variables and examined whether responses were immediate or long-term. There was no evidence of a strong effect of the hurricane on the abundances of six species. Estimates of the effects on five species were too uncertain to draw inferences. We detected positive and negative effects of the hurricane on the abundances of the remaining six species, but the magnitude of effects often was small. Generally, the effects were in the expected direction: negative on birds associated with mature forest and positive on birds associated with open land or young forest. We found evidence of an increase in the proportion of species that nest on the ground and a decrease in the proportion of species that nest in cavities and trees. In contrast, the hurricane had no discernible effect on functional measures of diversity (richness, evenness or divergence), or on communities’ reproductive or morphological characteristics. Our results suggest that the hurricane affected bird populations and communities, but the magnitude of effects was generally small. (Less)

Invasive alien plants are considered a major driver of global biodiversity loss. Therefore, there is a huge demand of spatial and temporal data on their distribution for investigating possible drivers of species invasions and for predictions of future distributions. We use Google Street View imagery (GSV) as a new source of spatial and temporal data. GSV provides millions of panoramic views along road networks worldwide allowing for the identification of many plant species, including invasive ones. Thus, GSV has a great potential to support ecological research in documenting species distribution, but reliable validation of its precision and accuracy is lacking. Here, we describe and evaluate an approach using GSV to visually track the spread of invasive alien plants, the North American goldenrods (Solidago canadensis and S. gigantea) occurring abundantly along road network in Poland (Central Europe). We determined presence/absence of the species along 160 randomly selected transects of a length of 500 m by visual inspection of GSV images and compared it with field surveys at the same transects. We show that the occurrence of goldenrods in GSV is a reliable predictor of their occurrence in the wild. Sampling parameters, like road width, season when GSV pictures were taken and number of months elapsed since taking the GSV pictures, did not change the correlation between outputs of the two methods (GSV and field sampling). Furthermore, both the occurrence of goldenrods observed in the field and their occurrence in GSV have similar relations to habitat characteristics investigated (the same direction of relationship and similar effect size). We suggest Google Street View images may be an additional tool to be used in the detection and tracking of the spread of invasive alien plants along roadsides. The approach may be useful in assessing temporal changes in roadside vegetation and managing problematic plant species across large spatial scales and may contribute to the further development of more efficient sampling methods in ecological studies.

The delivery of rigorous and unbiased evidence on the effects of interventions lay at the heart of the scientific method. Here we examine scientific papers evaluating agri‐environment schemes, the principal instrument to mitigate farmland biodiversity declines worldwide. Despite previous warnings about rudimentary study designs in this field, we found that the majority of studies published between 2008 and 2017 still lack robust study designs to strictly evaluate intervention effects. Potential sources of bias that arise from the correlative nature are rarely mentioned, and results are still promoted by using a causal language. This lack of robust study designs likely results from poor integration of research and policy, while the erroneous use of causal language and an unwillingness to discuss bias may stem from publication pressures. We conclude that scientific reporting and discussion of study limitations in intervention research must improve and propose some practices toward this goal.

Assessing the source–sink status of populations and habitats is of major importance for understanding population dynamics and for the management of natural populations. Sources produce a net surplus of individuals (per capita contribution to the metapopulation > 1) and will be the main contributors for self‐sustaining populations, whereas sinks produce a deficit (contribution, To access the source‐sink status of populations and habitats, the authors developed a novel integrated population model (IPM) that adjusts survival estimates for emigration outside the study area by using information about local movements. The authors show that spatial‐IPM can allow better assessment of source‐sink dynamics and better informed conservation interventions.

Abundant citizen science data on species occurrences are becoming increasingly available and enable identifying composition of communities occurring at multiple sites with high temporal resolution. However, for species displaying temporary patterns of local occurrences that are transient to some sites, biodiversity measures are clearly dependent on the criteria used to include species into local species lists. Using abundant opportunistic citizen science data from frequently visited wetlands, we investigated the sensitivity of α‐ and β‐diversity estimates to the use raw versus detection‐corrected data and to the use of inclusion criteria for species presence reflecting alternative site use. We tested seven inclusion criteria (with varying number of days required to be present) on time series of daily occurrence status during a breeding season of 90 days for 77 wetland bird species. We show that even when opportunistic presence‐only observation data are abundant, raw data may not produce reliable local species richness estimates and rank sites very differently in terms of species richness. Furthermore, occupancy model based α‐ and β‐diversity estimates were sensitive to the inclusion criteria used. Total species lists (all species observed at least once during a season) may therefore mask diversity differences among sites in local communities of species, by including vagrant species on potentially breeding communities and change the relative rank order of sites in terms of species richness. Very high sampling effort does not necessarily free opportunistic data from its inherent bias and can produce a pattern in which many species are observed at least once almost everywhere, thus leading to a possible paradox: The large amount of biological information may hinder its usefulness. Therefore, when prioritizing among sites to manage or preserve species diversity estimates need to be carefully related to relevant inclusion criteria depending on the diversity estimate in focus., Very high sampling effort can produce a pattern in which many species are observed at least once almost everywhere, thus leading to a possible paradox: The large amount of biological information may hinder its usefulness. The distinction between site use based on ecologically informed species inclusion criteria for determining composition of species communities is particularly relevant when prioritizing among sites to manage or preserve.

Despite large conservation efforts to halt the loss of farmland biodiversity in Europe, negative population trends are still observed, especially for common species. Old villages and human settlements are biodiversity hotspots and important breeding habitats for farmland birds, but recent requirements for energy saving measures and improved living comfort have changed their architecture and habitats. Consequently, modernization of villages may negatively affect bird diversity due to the loss of nesting and foraging sites. We investigated how the abundance and diversity of birds breeding in 104 Polish villages varied in relation to the degree of modernization as estimated by the proportion of new and renovated homesteads. Abundance of building-nesting species, but not tree-nesting species, declined by 50% across a gradient of old to highly modernized villages. The contribution of new versus renovated houses to the observed decline was similar. Synthesis and applications. Rural modernization may have a dramatic effect on abundance of birds nesting on buildings, thus may be an important and overlooked contributor to farmland bird population declines in Europe. Villages and rural properties fall outside of current conservation policy as they are neither protected areas nor agricultural lands (where agri-environmental schemes can be applied). The observed conflict between sustainability goals such as increased building energy efficiency and biodiversity conservation suggests that sustainable rural development should better link modernization with conservation measures, for example, by constructing nesting sites when renovating and building new houses. The challenge is to design modern buildings that are both energy-efficient and biodiversity-friendly to generally improve quality of life for rural communities and to halt or reduce farmland bird declines in rural landscapes. Designers and architects can find inspiration from traditional architecture and add a variety of nest-box types.

L-M.C. and P.d.V. acknowledge support from the European Research Council (ERC) (Grant 678140-FluctEvol). The Montpellier tit group acknowledges the long-term support of the Observatoire des Sciences de l’Univers – Obser-vatoire de REcherche Montpelliérain de l’Environnement (OSU-OREME). The bighorn, mountain goat, and eastern gray kangaroo studies were supported by Natural Sciences and Engineering Research Council (NSERC) of Canada. Recent data collection for Wytham has been provided by grants from Biotechnology and Biological Sciences Research Council (BB/L006081/1), ERC (AdG250164), and the UK Natural Environment Research Council (NERC) (NE/K006274/1, NE/S010335/1). The Columbian ground squirrel study was supported by the National Science Foundation (Grant DEB-0089473). Trait and fitness data for hihi were collected/managed by John Ewen under New Zealand Department of Conservation hihi management contracts and research permits AK/15073/RES, AK-24128-FAU, 36186-FAU, and 44300-FAU and with additional financial support via NERC UK, The Leverhulme Trust UK, Marsden Fund New Zealand, and the Hihi Conservation Charitable Trust. The data on reindeer were made available through the Reindeer husbandry in a Globalizing North Nordic Center of Excellence, and the crew at Kutuharju Experimental Reindeer Research Station in the Reindeer Herder’s Association are thanked for their valuable assistance and logistic support in data collection. The red deer, Silwood blue tit, and Soay sheep datasets were supported by UK NERC. Lundy sparrow data were supported by NERC, a Marie Skłodowska-Curie Action, and Volkswagenstiftung. The red squirrel project was funded by NSERC of Canada and the National Science Foundation. J.C.S. was supported by a grant from the Ministry of Economy and Competitivity, Spanish Research Council (CGL-2016-79568-C3-3-P). J.T., T.K., and M.G. were supported by the Research Council of Norway through its Centers for Excellence funding scheme, Project 223257. Research on fairy wrens has been supported by the Australian Research Council. The Northern wheatear and the flycatcher studies were supported by grants from the Swedish Research Council VR. Temporal variation in natural selection is predicted to strongly impact the evolution and demography of natural populations, with consequences for the rate of adaptation, evolution of plasticity, and extinction risk. Most of the theory underlying these predictions assumes a moving optimum phenotype, with predictions expressed in terms of the temporal variance and autocorrelation of this optimum. However, empirical studies seldom estimate patterns of fluctuations of an optimum phenotype, precluding further progress in connecting theory with observations. To bridge this gap, we assess the evidence for temporal variation in selection on breeding date by modeling a fitness function with a fluctuating optimum, across 39 populations of 21 wild animals, one of the largest compilations of long-term datasets with individual measurements of trait and fitness components. We find compelling evidence for fluctuations in the fitness function, causing temporal variation in the magnitude, but not the direction of selection. However, fluctuations of the optimum phenotype need not directly translate into variation in selection gradients, because their impact can be buffered by partial tracking of the optimum by the mean phenotype. Analyzing individuals that reproduce in consecutive years, we find that plastic changes track movements of the optimum phenotype across years, especially in bird species, reducing temporal variation in directional selection. This suggests that phenological plasticity has evolved to cope with fluctuations in the optimum, despite their currently modest contribution to variation in selection. Postprint

In Europe, agri-environmental schemes (AES) have been unsuccessful in halting biodiversity declines to any great extent. Two particular shortcomings of AES include the low farm uptake and the modest efficacy of many AES options. Partly in response to these shortcomings, initiatives encouraging farmers to take an active role in biodiversity conservation have gained in popularity. However, almost no evaluations of such initiatives exist. 2. We evaluated uptake of conservation advice on farms in the Swedish Volunteer & Farmer Alliance, a BirdLife Sweden-coordinated project aimed at farmland bird conservation, and the response of farmland birds to those actions using farm-level survey data, in a before-after implementation assessment. 3. Uptake was higher for unsubsidised (i.e. non-AES) measures than for AES options, and depended on farmers’ interest in nature, farm size (higher uptake on larger farms) and production type (higher on organic farms). 4. In general, abundances of non-crop nesting and field-nesting bird species declined between inventory years (median interval 3 years). Decreases were more marked in agriculturally marginal regions than in more arable-dominated regions, and declines were stronger on organic than conventional farms. 5. Negative abundance trends among non-crop nesting species were reduced by an increasing number of conservation measures at the farm, but only in the more arable-dominated landscapes. Changes in other non-crop species and in field-nesting species did not significantly relate to implemented measures, but the power to detect such effects was generally small due to the small sample size of high-uptake farms as well as high inter-farm variability. 6. Implications: Our results suggest that Volunteer Farmer Alliances and the addition of unsubsidised measures may be successful in changing the local number of non-crop nesting farmland birds at the farm level, and especially so in intensively managed agricultural landscapes. Thus, unsubsidised measures can be a useful addition to the set of agri-environment tools, although their effects on breeding bird numbers are (as with AES) dependent on landscape context, as well as on ensuring high on-farm uptake of different interventions.

Populations of meadow waders have shown steep declines in Europe during recent decades. However, empirical evidence concerning habitat preferences of different species in east Europe is largely lacking. In this study we investigate occurrence of the Eurasian curlew (Numenius arquata), black-tailed godwit (Limosa limosa), common redshank (Tringa totanus) and northern lapwing (Vanellus vanellus) in 413 grassland plots (c. 50,000 ha in total) located in Polish lowland surveyed three times during spring of 2015 and 2016. Using hierarchical occupancy models corrected for imperfect detection we link local water conditions, forest cover and scattered trees and presence of cows and buildings with occurrence of waders. Presence of godwit positively correlated with flooding and wetness while negatively with drainage ditches and single trees. Redshank was positively associated with flooding and negatively with ditches and proximity to buildings. Lapwing was less often observed in proximity to buildings and at sites with numerous trees whereas curlews, showed no clear associations with any of the environmental variables investigated. Detectability of studied species (except godwit) was higher when corvids were present suggesting that species interactions may affect detection. Field survey conditions (e.g. time of day, number of visit) also contributed to detectability of all studied species. Our study suggest that water availability, including natural flooding, increases habitat quality for breeding waders, while single trees and farm buildings may reduce grassland availability for these species. Thus waders-oriented agri-environment subsidies, besides adjusting grassland management to breeding phenology, should also focus on wetness and openness of grasslands.

Dispersal is a key life history trait impacting ecological and evolutionary processes. Yet, the fitness consequences of dispersal remain poorly investigated. Using a displacement experiment of 616 individuals in a patchy population of collared flycatchers, Ficedula albicollis, we investigated behavioural responses to forced movement in terms of settlement, subsequent breeding performance and return rate. Newly arrived birds were caught and displaced between patches or released back in the patch of capture. We analysed (1) the probability of successful settlement within the study area, (2) for displaced birds, the probability of accepting the forced movement rather than returning to the patch of capture, (3) components of reproductive performance and (4) return rate in subsequent years according to experimental treatment. The probability of settling within the study area tended to be lower for displaced than control birds and was lower for immigrants than local birds. This suggests that displacement induced long-distance dispersal movements or nonbreeding, which could reflect costs of unfamiliarity with the environment. Nondispersers (individuals caught early in the breeding season in the same patch as their previous one) were more likely to return to their patch of capture, probably because of higher benefits of familiarity. Once individuals had settled, their breeding performance did not vary markedly between treatments, although displaced individuals that did not return to their patch of capture raised lighter young than other individuals. This could indicate a lower phenotypic quality of these individuals or, again, a cost of breeding in an unfamiliar environment. Finally, individuals that settled (and nondispersers) were more likely to return to the study area in subsequent years than individuals that disappeared (and immigrants/dispersers, respectively). Together, these results suggest that, in addition to the costs of transience, dispersal (here forced) may entail costs linked to settlement in an unfamiliar habitat.

The seasonal timing of reproduction is a major fitness factor in many organisms. Commonly, individual fitness declines with time in the breeding season. We investigated three suggested but rarely tested hypotheses for this seasonal fitness decline: (1) time per se (date hypothesis), (2) late breeders are of lower quality than early ones (individual quality hypothesis), and (3) late breeders are breeding at poorer territories than early ones (territory quality hypothesis). We used Bayesian variance component analyses to examine reproductive output (breeding success, number fledged, and number of recruits) from repeated observations of female northern wheatears (Oenanthe oenanthe) and individual territories from a 20-year population study. The major part of the observed seasonal decline in reproductive output seemed to be driven by date-related effects, whereas female age and territory type (i.e. known indicators of temporary quality) contributed to a smaller degree. Other, persistent effects linked to individual and territory identity did not show any clear patterns on the seasonal decline in reproductive output. To better disentangle the quality effects (persistent and temporary) of individual and territory from effects caused by the deterioration of the environment we suggest a protocol combining experimental manipulation of breeding time with a variance-covariance partitioning method used here. This article is protected by copyright. All rights reserved.

The Northern Wheatear (Oenanthe oenanthe, including the nominate and the two subspecies O. o. leucorhoa and O. o. libanotica) and the Seebohm’s Wheatear (Oenanthe seebohmi) are today regarded as two distinct species. Before, all four taxa were regarded as four subspecies of the Northern Wheatear. Their classification has exclusively been based on ecological and morphological traits, while their molecular characterization is still missing. With this study, we used next-generation sequencing to assemble 117 complete mitochondrial genomes covering O. o. oenanthe, O. o. leucorhoa and O. seebohmi. We compared the resolution power of each individual mitochondrial marker and concatenated marker sets to reconstruct the phylogeny and estimate speciation times of three taxa. Moreover, we tried to identify the origin of migratory wheatears caught on Helgoland (Germany) and on Crete (Greece). Mitogenome analysis revealed two different ancient lineages that separated around 400,000 years ago. Both lineages consisted of a mix of subspecies and species. The phylogenetic trees, as well as haplotype networks are incongruent with the present morphology-based classification. Mitogenome could not distinguish these presumed species. The genetic panmixia among present populations and taxa might be the consequence of mitochondrial introgression between ancient wheatear populations.

Currently, the deployment of tracking devices is one of the most frequently used approaches to study movement ecology of birds. Recent miniaturization of light‐level geolocators enabled studying small bird species whose migratory patterns were widely unknown. However, geolocators may reduce vital rates in tagged birds and may bias obtained movement data. There is a need for a thorough assessment of the potential tag effects on small birds, as previous meta‐analyses did not evaluate unpublished data and impact of multiple life‐history traits, focused mainly on large species and the number of published studies tagging small birds has increased substantially. We quantitatively reviewed 549 records extracted from 74 published and 48 unpublished studies on over 7,800 tagged and 17,800 control individuals to examine the effects of geolocator tagging on small bird species (body mass, + Publisher's Statement: This is the peer reviewed version of the following article: "Brlík, V, Koleček, J, Burgess, M, et al. Weak effects of geolocators on small birds: A meta‐analysis controlled for phylogeny and publication bias. J Anim Ecol. 2020; 89: 207– 220", which has been published in final form at https://doi.org/10.1111/1365-2656.12962. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.; Read Only Lizenz.