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Protected areas are a key component in biodiversity conservation strategies, but evaluations of how effective they are in capturing species diversity is lacking for many ecosystems. We compared different protection types (animal sanctuaries, nature reserves and unprotected areas) using data on species richness and occurrence of coastal breeding bird species in a large archipelago in the Baltic Sea. Data were from extensive inventories based on a grid with 1 × 1 km resolution covering 4646 km2 on the East coast of Sweden. We focused on specialist species breeding exclusively in coastal habitats since these species are of specific conservation concern, but considered generalists, which also breeds in inland wetlands, as well. Animal sanctuaries had significantly higher species richness of specialist species than unprotected areas and nature reserves. Nature reserves had even lower richness of specialist species than unprotected areas. Further, a rarity-weighted diversity index showed that animal sanctuaries were better in capturing hotspots of bird diversity compared to nature reserves and unprotected areas. Hotspots, both protected and unprotected, were scattered throughout the entire archipelago. The rarity-weighted richness is therefore useful to identify gaps in the protected area network. Overall, we conclude that the establishment of animal sanctuaries has been a successful conservation measure for protecting specialist species in several aspects. Ongoing human exploitation of the Baltic archipelagos prompt further consideration of protecting still unprotected but species rich shorelines for the benefit of many coastal breeding birds. Keywords: Animal sanctuaries, Area protection, Coastal breeding birds, Nature reserves, Rarity-weighted richness, Human exploitation

Wetland creation is a common conservation practice to mitigate biodiversity loss, caused by global wetland destruction. Despite this, there is a lack of large-scale evaluations of how created wetland characteristics and landscape context relate to bird diversity and reproductive success. We inventoried 89 created wetlands (0.2–20 ha) in central Sweden to investigate which local and landscape components were associated with breeding wetland bird species richness, pair abundance and reproductive success. Wetland size was positively associated with species richness, pair abundance and chick abundance. However, several small (1 ha) wetlands taken together were similar to or exceeded individual large wetlands of similar total wetland area, in terms of species richness, pair abundance, and chicks produced. While species richness showed a clear negative relationship with the proportion of the adjacent 50 m buffer composed of forest, pair abundance was positively related to the proportion of flooded grassland area and negatively related to the proportion of emergent water vegetation. Reproductive success measures showed no clear relationships to local habitat characteristics but tended to increase with a decreasing forest at the landscape scale. Our results suggest that breeding wetland bird populations could benefit from creating wetlands with a high flooded area, continuous management to minimise both the area of emergent water vegetation and the establishment of shrubs and trees in the immediate surroundings. We also suggest a practice of creating mainly small wetlands with a few larger ones to facilitate breeding wetland bird communities at the regional scale (gamma diversity).

Biodiversity offsetting is becoming a principal instrument for managing biodiversity and ecosystem services in society. Still, it is unclear whether biodiversity offsetting can fully mitigate losses to natural values. When reviewing published studies on offsetting, we found only 40 evaluations with primary outcome data on biodiversity or ecosystem services. Among these, we found no evidence that biodiversity gains from offsets actually compensate for development-associated losses, because losses were never estimated. The failure to quantify losses is troubling from a conservation perspective, as applying offsets that do not match up losses and gains will result in continued net loss of biodiversity. Instead, most studies (76%) included only reference habitats as comparator and evaluated singular taxa of biodiversity (66%), and rarely ecosystem services (ES). The overall meta-analysed effect size from reference habitat comparisons suggests that offsets perform poorly when contrasted to these habitats. There was a strong bias towards North American freshwater biomes, with only six published evaluations from terrestrial habitats. The bias and small number of studies precluded any detailed meta-analytical enquiries, such as identification of main drivers of outcomes. For biodiversity offsetting to be an important instrument for halting biodiversity losses, all actions must build on solid scientific evidence, and our review show that this evidence base is yet not in place. We conclude that there is a strong need for rigorous evaluation of offsetting projects, and to this end governments could request long-term monitoring programmes as an integral part of offsetting actions and make data openly available for assessment.

Predicting suitable locations for invasive alien terrestrial vertebrates (IATV) under different scenarios of global change is essential for local and transboundary management aimed to prevent the spread of invasions. Using a spatial modelling approach adapted to invasive species, we identify range-shifts in suitable areas for 15 of the most harmful IATV in Europe, considering future climate and land-use changes. We predict range contractions for seven of these IATV, expansion for four, and inconclusive outputs for the rest. For most Europe, future aggregated distributions show stable or decreasing trends in total IATV richness. Still, specific regions will increase their suitability for additional IATVs, including some protected and last-of-the-wild areas. Our results are informative for early decision-making and long-term strategies to prevent negative effects of IATV. Our approach is based on publicly available data, so predictions can be revised as new data becomes available.

The Polish breeding population (3,200–3,250 males) of the globally threatened Aquatic Warbler Acrocephalus paludicola represents almost 25% of the global population. Except for the relatively stable large population in the Biebrza valley in north-east Poland less is known about population trends of peripheral populations in western, central and south-eastern regions of the country and whether trends differ depending on region. We investigated the long-term population dynamics in 38 small populations between 1969–2013 in the four Polish regions. Summarizing the trends of all small populations of Aquatic Warblers showed a significant decline in total number of individuals and declining number of populations over time. However, population trends were distinctly different in the different regions, with stable dynamics in south-east, moderate decline in north-east and sharp decline in the central and western regions. During the study period 19 out of 38 populations became extinct (11 populations in t...

Forest clear-cuts may offer suitable habitats for farmland birds, however empirical evidence on the effect of clear-cut size, age and distance from farmland habitats is largely lacking. In this study we investigated local (alpha) and total (gamma) diversity of farmland birds in 137 clear-cuts in a large forest in western Poland. Eighteen farmland bird species were recorded, of which 10 are included in the Polish Farmland Bird Index. Local alpha diversity of farmland birds was higher in older (5–10 yrs) and larger clear-cuts and declined with increasing distance to the forest-farmland edge. Local species communities displayed a high degree of turnover among clear-cuts and the gamma diversity of farmland birds was nearly twice as high in clear-cuts located close to the forest-farmland edge (i.e. below 1.3 km from the edge; 17 species) compared to clear-cuts located in the forest interior (9 species), and in large clear-cuts (i.e. over 3.1 ha, 17 species) compared to small clear-cuts (9 species). Our study shows that the additional habitat of clear-cuts in forest landscapes may potentially contribute to overall biodiversity of farmland birds in a region and should thus be included in monitoring and conservation of farmland birds.

Summary Crop diversification has been introduced as an environmental strategy in the ‘Greening’ of the EU Common Agricultural Policy (CAP) for 2015–2020. The primary target of crop diversification is soil and ecosystem resilience, but claims for potential benefits for farmland biodiversity are also common. However, understanding of relationships between the number (compositional heterogeneity) and spatial arrangement (configurational heterogeneity) of crop fields and biodiversity is generally poor, making such claims relatively unfounded. In this study, we monitored crop and farmland bird diversity on 178 farms across Sweden's main agricultural areas. From a pre-implementation assessment, we show that >97% of the assessed farms would not be required to change their management under the CAP crop diversification measure (minimum of three crops for farms with 30+ ha), suggesting that this measure has generated little change on Swedish farms. While accounting for non-crop elements and farming system (conventional or organic), we show that crop structural diversity (i.e. the management and vegetation structure of crops) rather than crop diversity senso lato positively affected richness of non-crop breeding bird species with stronger effects in arable, compared with forest-dominated landscapes. No such effects were observed among field-nesting farmland bird species. Organic farming had little influence on farmland birds with positive effects only in the most arable-dominated landscapes and for field-nesting species only. In forest-dominated landscapes, organic farms even held lower field-nester densities compared with conventional farms, possibly due to the dominance of grasslands on organic farms that in these landscapes support lower densities of field-nesting species compared with cereals. Policy implications. Our study illustrates the importance of a consideration of structural instead of species diversity of crops for biodiversity, in this case farmland birds. We also underline the absence of such a distinction in current EU Common Agricultural Policy Greening, while simultaneously setting levels on crop diversification too low resulting in little to no change in landscape-scale crop diversity on Swedish farmland. We recommend that future efforts to manage farmland biodiversity should include ways of increasing the structural diversity of crops at the scale of farms and landscapes.

Summary To counteract the decline of farmland biodiversity in Europe, it is crucial to recognize habitats that are hot spots. Old rural settlements (e.g. villages) may be such important habitats, although these presumably biodiversity-rich habitats have received little attention. Socio-economic changes in central-eastern Europe since 1989 mean that old homesteads and farmsteads are being replaced by new ones. We investigated bird species composition, richness and abundance at three spatial scales (single rural property, village and landscape) in the farmland of Poland to test: (i) their association with age (built before vs. after 1989) and type of property (farmstead vs. homestead), (ii) their relationship with the increasing share of new homesteads at the village scale and (iii) the difference in diversity between the village environment and four other environments (open fields, forest–field ecotones, forests and towns) at the landscape scale. At the single property scale, 15 out of 33 species preferred old farmsteads, while only one species preferred new homesteads. Old properties hosted a higher number of species and individuals than new ones, and farmsteads hosted a higher number of species than homesteads. At the village scale, bird species richness and abundance were markedly negatively associated with the proportion of new homesteads. At the landscape scale, species composition differed between villages and the other environments, and villages had the highest average bird abundance. Synthesis and applications. Rural villages and old farmsteads are important habitats for many farmland birds; thus, the increasing number of new homesteads not associated with farmland production will likely lead to a substantial further decline of farmland bird numbers and biodiversity. To counteract this process, we recommend (i) implementing educational programmes to develop rural residents’ awareness about the importance of farmsteads and homesteads for biodiversity, (ii) including villages and farmsteads and consideration of bird-friendly habitats within these as part of EU conservation policies and (iii) compensating for changes in the structure of rural villages by increasing the amount of similar alternative habitats in the surrounding landscape.

To halt the decline of biodiversity in European farmland, two major tools are available: the Natura 2000 network and agri-environment schemes (AES). We investigated the effect of these two measures on local species richness, single species occurrence and beta diversity of grassland birds in Poland. We counted birds on AES parcels (with less intensive grassland management) and control parcels, both within and outside Special Protection Areas (SPAs, part of Natura 2000), during 2013–2014. Local species richness of AES-target birds was not associated with AES. Similarly, the turnover of AES-target species among sites was comparable at AES and control parcels. Furthermore, no positive interaction between AES and SPAs was observed, indicating a general lack of effect of AES. Local species richness of SPA-target birds was not higher within than outside SPAs, but two SPA-target species were more common and the beta diversity of SPA-target species was higher within than outside SPAs. Thus, our study showed no positive effects of AES on the occurrence of their target species, but confirmed some positive effects of SPAs on their target species. The decision to restrict AES to Special Protection Areas in 2015–2020 has no justification in our analyses. Actually, many AES-target species will be protected within SPAs irrespective of whether the area is an AES or not, but future AES should also include parcels outside SPAs, as many target species occur there. However, to improve the effectiveness of AES management prescriptions should be diversified and customized to meet the largely different habitat preferences of present target species (such as, for instance, the lapwing and corncrake).

Summary Nearly 60% of European wetlands have been lost to drainage or to the cessation of grassland management. Large amounts of resources are put into wetland restoration with the aim to recover biodiversity. However, few studies have simultaneously evaluated effects of management, wetness and flooding dynamics on biodiversity of restored wetlands such as seasonally flooded wet grasslands. We inventoried bird communities over 4 years at 137 sites (each 3·1 ha) within five restored wet grassland areas in Sweden to investigate whether species richness and occurrence of 12 common wet grassland species were related to (i) local conditions such as management (grazing, mowing and unmanaged areas), basic wetness and spring flooding dynamics. Further, we investigated whether (ii) the composition of the adjacent landscape (20 ha) related to local bird diversity and (iii) species turnover (i.e. beta diversity) differed between sites characterized by their basic wetness, degree of flooding and predominant management regime. Local species richness was positively linked to degree of flooding and basic wetness of grasslands but not to type of grassland management. Species richness tended also to be negatively linked to proportion of forest at the landscape scale. Although variable, the same results were also true concerning the probability of the occurrence of a single species at the local scale. Species turnover between sites, and thus total species richness, was distinctly higher in (i) grazed as compared to mowed grasslands except in dry non-flooded grasslands and (ii) flooded as compared to non-flooded sites. Similar patterns held for the subset of 12 red-listed species. We suggest that the high beta diversity in grazed and flooded grasslands is driven by the heterogeneous vegetation structure, resulting in good conditions for foraging and nesting for several wet grassland bird species. Synthesis and applications. The selection of wetlands for conserving wet grassland birds should prioritize temporary flooded grasslands of moderate wetness, preferably far from forest edges. Restoration and management of wet grasslands should include water level management, removal of shrubs and trees, and low-intensity grazing, whereas mowing could be used in non-flooded grasslands of low basic wetness.

Variation of habitats and resources important for farmland birds seems to be only partly captured by ordinary statistics on land-use and agricultural production. For instance, densities of rodents being prey for owls and raptors or structures of rural architecture providing nesting sites for many species are central for bird diversity but are not reported in any official statistics. Thus, modelling species distributions, population abundance and trends of farmland birds may miss important predictive habitat elements. Here, we involve local socio-economy factors as a source of additional information on rural habitat to test whether it improves predictions of barn owl occurrence in 2768 churches across Poland. Barn owls occurred in 778 churches and seemed to prefer old churches made of brick located in regions with a milder climate, higher share of arable land and pastures, low road density and low levels of light pollution. Including data on local unemployment, the proportion of elder citizens, commune income per citizen, the share of citizens with high education and share of farmers among working population improved the model substantially and some of these variables predicted barn owl occurrence better than several land-use and climate data. Barn owls were more likely to occur in areas with high unemployment, a higher proportion of older citizens in a local population and higher share of farmers among working population. Importantly, the socio-economy variables were correlated with the barn owl occurrence despite all climatic, infrastructure and land-use data were present in the model. We conclude that the socio-economy of local societies may add important but overlooked information that links to spatial variation in farmland biodiversity.

Woodpecker diversity is usually higher in natural forests rich in dead wood and old trees than in managed ones, thus this group of birds is regarded as an indicator of forest biodiversity. Woodpeckers excavate cavities which can be subsequently used by several bird species. As a consequence, their abundance indicates high avian abundance and diversity in forests. However, woodpecker-made holes may be also important for other animals, for example, mammals but it has seldom been investigated so far. Here, we examine how well one species, the Great Spotted Woodpecker, predicts species richness, occurrence and acoustic activity of bats in Polish pine forests. In 2011 we conducted woodpecker and bat surveys at 63 point-count sites in forests that varied in terms of stand age, structure and amount of dead wood. From zero to five Great Spotted Woodpeckers at a point-count site were recorded. The total duration of the echolocation calls during a 10-min visit varied from 0 to 542 s and the number of bat species/species groups recorded during a visit ranged between zero to five. The local abundance of the woodpecker was positively correlated with bat species richness (on the verge of significance), bat occurrence and pooled bat activity. The occurrence of Eptesicus and Vespertilio bats and Nyctalus species was positively related with the abundance of the Great Spotted Woodpecker. The activity of Pipistrellus pygmaeus, Eptesicus and Vespertilio bats and a group of Myotis species was not associated with the woodpecker abundance, but echolocation calls of Nyctalus species, P. nathusii and P.pipistrellus were more often at sites with many Great Spotted Woodpeckers. Moreover, the probability of bat presence and the activity of bats was generally higher shortly after dusk and in middle of the summer than in late spring. We suggest that the observed correlations can be driven by similar roosting habitats (e.g., woodpeckers can provide breeding cavities for bats) or possibly by associated invertebrate food resources of woodpeckers and bats. The abundance of Great Spotted Woodpecker seems to be a good positive indicator of bat species richness, occurrence and activity, thus adding a group of relatively cryptic forest species that are indicated by the presence of the Great Spotted Woodpecker.

Binomial N-mixture models are commonly applied to analyze population survey data. By estimating detection probabilities, N-mixture models aim at extracting information about abundances in terms of actual and not just relative numbers. This separation of detection probability and abundance relies on parametric assumptions about the distribution of individuals among sites and of detections of individuals among repeat visits to sites. Current methods for checking assumptions are limited, and their computational complexity have hindered evaluations of their performances. We develop computationally efficient graphical goodness of fit checks and measures of overdispersion for binomial N-mixture models. These checks are illustrated in a case study, and evaluated in simulations under two scenarios. The two scenarios assume overdispersion in the abundance distribution via a negative binomial distribution or in the detection probability via a beta-binomial distribution. We evaluate the ability of the checks to detect lack of fit, and how lack of fit affects estimates of abundances. The simulations show that if the parametric assumptions are incorrect there can be severe biases in estimated abundances: negatively if there is overdispersion in abundance relative to the fitted model and positively if there is overdispersion in detection. Our goodness of fit checks performed well in detecting lack of fit when the abundance distribution is overdispersed, but struggled to detect lack of fit when detections were overdispersed. We show that the inability to detect lack of fit due to overdispersed detection is caused by a fundamental similarity between N-mixture models with beta-binomial detections and N-mixture models with negative binomial abundances. The strong biases in estimated abundances that can occur in the binomial N-mixture model when the distribution of individuals among sites, or the detection model, is mis-specified implies that checking goodness of fit is essential for sound inference in ecological studies that use these methods. To check the assumptions we provide computationally efficient goodness of fit checks that are available in an R-package nmixgof. However, even when a binomial N-mixture model appears to fit the data well, estimates are not robust in the presence of overdispersion unless additional information about detection is collected.

In many migratory birds, males precede females during migration and arrival at the breeding sites. Three proximate mechanisms are proposed to explain this phenomenon of protandry: males 1) winter closer to breeding sites, 2) start spring migration earlier, and/or 3) migrate faster than females. So far, the relative contribution of these mechanisms to protandry is unknown. The present study investigated the importance of each of the 3 proximate mechanisms of protandry for a songbird migrant wintering in Africa, the northern wheatear (Oenanthe oenanthe). Two subspecies co-occur in Europe on migration, of which the leucorhoa northern wheatears breeding from Iceland to Canada have to cross the North Atlantic, whereas the nominate form breeding in Europe does not face any significant sea barrier. We show that the leucorhoa subspecies had a significantly higher degree of protandry at stopover sites across Europe than the oenanthe subspecies (−6 vs. −2 days). Leucorhoa northern wheatear’s higher degree of protandry was associated with a larger age effect, in which old males preceded young males, and greater sex-specific differences in wing shape and refueling yielding higher migration speeds in males than females. In oenanthe northern wheatears, light-level geolocators revealed that males did not winter closer to the breeding sites or migrate faster than females, but initiated spring migration earlier. Our results demonstrate that the significance of the mechanisms causing protandry can differ between related taxa and highlight the importance of the advancement in male arrival date with age as a potential factor shaping the degree of protandry.

Context Habitat heterogeneity is often assumed to benefit farmland biodiversity. Increasing heterogeneity of non-crop habitats is often too costly in terms of agricultural production. It has been suggested that increased crop heterogeneity could mitigate the negative effects of intensification on biodiversity while still maintaining high production levels. Objectives We investigated if habitat-specific species pools of two groups of farmland birds, fieldnesting and non-crop-nesting species, were related to landscape-level heterogeneity of crop and non-crop cover. We analysed total number of species (gamma diversity) and average local species richness (alpha diversity) in landscapes and related these two biodiversity measures to four components of landscape heterogeneity (compositional and configurational heterogeneity of crop and non-crop cover). Methods We selected 30 farmland landscapes (each 25 km 2 ) in Sweden that largely broke up correlated relationships between crop and non-crop heterogeneity and between compositional and configurational heterogeneity. Estimates of species richness (alpha and gamma diversity) were calculated with bird survey data from specific habitats within landscapes (farmsteads and arable fields) and then related to measures of landscape heterogeneity. Results No measure of landscape species richness was associated with landscape-scale crop cover heterogeneities. However, gamma diversity of both bird groups was negatively related to the compositional and configurational heterogeneity of non-crop land-use in the landscapes, respectively. Conclusions Our results suggest that: (i) crop heterogeneities are not related to habitat-specific richness of farmland birds, (ii) heterogeneity effects of habitat complementarity in general are weak and (iii) relationships between diversity and heterogeneity in landscapes are dependent on the biodiversity measure used.

Stopover behaviour is a central element of migration strategies. But in recent geolocator studies, despite now being able to track individual songbirds during their entire migration, their stopover behaviour has received little attention. We used light-sensitive geolocators to identify the migratory routes and schedules of 12 northern wheatears (Oenanthe oenanthe) breeding in Sweden. Three geolocators collected temperature data complementing inferences from light data by providing additional information on behaviour during migration. The wheatears performed a slow migration with considerable stopover time (84%/76% of autumn/spring migration), with short stops while traveling through Europe, and a prolonged stopover period in both autumn and spring in the Mediterranean region. Spring migration was faster than autumn migration, mainly because of decreased stopover time. Migration routes and time schedules were similar to those from a German breeding population. Compared to wheatears breeding in Alaska with a three-fold migration distance, Swedish wheatears spent more time during stopovers during autumn and spring migration, suggesting less time constraints and potential flexibility in migration schedules. The finding of prolonged stopovers, similar to other recent geolocator studies, shows that temporary residency periods may be common. This changes our current view on stopover ecology to one where temporary residency periods are part of spatio-temporal strategies optimising resource use during the entire annual cycle.

Binomial N-mixture models are commonly applied to analyze population survey data. By estimating detection probabilities, N-mixture models aim at extracting information about abundances in terms of actual and not just relative numbers. This separation of detection probability and abundance relies on parametric assumptions about the distribution of individuals among sites and of detections of individuals among repeat visits to sites. Current methods for checking assumptions are limited, and their computational complexity have hindered evaluations of their performances.We develop computationally efficient graphical goodness of fit checks and measures of overdispersion for binomial N-mixture models. These checks are illustrated in a case study, and evaluated in simulations under two scenarios. The two scenarios assume overdispersion in the abundance distribution via a negative binomial distribution or in the detection probability via a beta-binomial distribution. We evaluate the ability of the checks to detect lack of fit, and how lack of fit affects estimates of abundances.The simulations show that if the parametric assumptions are incorrect there can be severe biases in estimated abundances: negatively if there is overdispersion in abundance relative to the fitted model and positively if there is overdispersion in detection. Our goodness of fit checks performed well in detecting lack of fit when the abundance distribution is overdispersed, but struggled to detect lack of fit when detections were overdispersed. We show that the inability to detect lack of fit due to overdispersed detection is caused by a fundamental similarity between N-mixture models with beta-binomial detections and N-mixture models with negative binomial abundances.The strong biases in estimated abundances that can occur in the binomial N-mixture model when the distribution of individuals among sites, or the detection model, is mis-specified implies that checking goodness of fit is essential for sound inference in ecological studies that use these methods. To check the assumptions we provide computationally efficient goodness of fit checks that are available in an R-package nmixgof. However, even when a binomial N-mixture model appears to fit the data well, estimates are not robust in the presence of overdispersion unless additional information about detection is collected.

Abstract Aim To improve predictions of spatial and temporal patterns of species richness it is important to consider how species presence at a site is defined. This is because this definition affects our estimate of species richness, which should be aligned with the aims of the study, e.g. estimating richness of the breeding community. Here we explore the sensitivity of species richness estimates to criteria for defining presence of species (e.g. in relation to number of days present during the breeding season) at 107 wetlands. Innovation We use opportunistic citizen science data of high density (a total of 151,817 observations of 77 wetland bird species; i.e. about 16 observations per day) to build site-occupancy models calculating occupancy probabilities at a high temporal resolution (e.g. daily occupancies) to derive probabilistic estimates of seasonal site use of each species. We introduce a new way for defining species presence by using different criteria related to the number of days the species are required to be present at local sites. We compared patterns of species richness when using these different criteria of species inclusions. Main conclusion While estimates of local species richness derived from high temporal resolution occupancy models are robust to observational bias, these estimates are sensitive to restrictions concerning the number of days of presence required during the breeding season. Unlike complete local species lists, summaries of seasonal site use and different presence criteria allow identifying differences between sites and amplifying the variability in species richness among sites. Thus, this approach allows filtering out species according to their phenology and migration behaviour (e.g. passer-by species) and could improve the explanatory power of environmental variables on predictive models.

To increase the efficacy of agri-environmental schemes (AES), as well as farmers' environmental engagement, practitioners are increasingly turning to collective forms of agri-environmental manage- ment. As yet, empirical evidence from such approaches is relatively scarce. Here, we examined a farm- land bird conservation project coordinated by BirdLife Sweden, the Swedish Volunteer & Farmer Alliance (SVFA). The key features of the SVFA were farmland bird inventories from volunteering birdwatchers and on-farm visits to individual farmers from conservation advisors for guidance on AES as well as unsub- sidised practices. Using an ex-post application of the theory of planned behaviour across project par- ticipants and a randomly sampled control group of farmers we assessed how SVFA affected behavioural intentions relating to AES and unsubsidised conservation, and how the behaviour was affected by atti- tudes, perceived social norms and perceived behavioural control. We also included a measure of self- identity as a conservationist to assess its importance for behavioural intentions, and if SVFA stimu- lated this self-identity. SVFA farmers reported greater commitment to implementing AES and unsubsi- dised conservation, as compared to the control group. However, greater commitment was associated with more positive attitudes for unsubsidised conservation only and not for AES, underlining the inability of existing AES to prompt intrinsic motivation. There were also differences between farmers within SVFA, where farmers applying to the project were motivated by social influences, while farmers recruited by project managers were motivated by their personal beliefs regarding nature conservation. Finally, farmers' self-perceived ability to perform practices (i.e. perceived behavioural control) was important for their commitment to implementing AES as well as unsubsidised practices. Therefore, increasing farmers' awareness regarding the availability and, not least, practicability of available con- servation options may be the key to successful biodiversity conservation in agricultural systems.

The loss of non-crop habitat is often suggested to be a key driver of biodiversity decline on arable land. Grass buffer strips on cereal field edges, to reduce erosion and agro-chemical runoff into surface water, could be useful to mitigate this diversity loss as they are often assumed to provide refuge and food for invertebrates, small mammals and birds. Evidence for this idea is, however, scarce and it remains unclear whether densely vegetated buffer strips benefit biodiversity in structurally complex landscapes of Northern Europe. Here, we examined whether buffer strips affected breeding skylark Alauda avensis numbers and its main food supply (i.e. beetles Coleoptera and spiders Arachnida) on cereal fields in a heterogeneous agricultural landscape of south-central Sweden. We also examined whether buffer strip effects on skylark density depended on seasonal sward height differences between sowing regimes (spring- vs. autumn-sown) as they presumably influence seasonal invertebrate accessibility. Fields with buffer strips supported on average 0.51 ± 0.26 more skylark territories per hectare up to 100 m into the field and boosted invertebrate activity densities compared to fields without buffer strips. These effects were most apparent early in spring, but persisted throughout the sampling period, and were similar among spring and autumn sown fields. Thus, our results provide evidence to suggest that buffer strips target multiple environmental objectives on cereal fields in heterogeneous farmland. Future research should work to identify buffer strip management practices that further increase their value to biodiversity at the local scale, and investigate how they affect farmland biodiversity in different landscape types at larger spatial scales for more efficient implementation across Europe.

In Europe, more than 20 billion Euros have been paid to farmers for agri-environment schemes (AESs) during the last half decade to counteract negative effects of farming on the environment. In Sweden alone 0.4 billion Euros are paid to farmers for AESs every year, but large-scale analyses of the relationship between AESs and biodiversity are scarce in northern Europe. We surveyed farmland birds at over 600 sites in non-crop habitats in 37 arable dominated landscapes (each 25 km2) in southern Sweden and investigated if bird species richness and abundance were related to the amount of agricultural land receiving subsidies for five common AESs. Abundance and species richness of three subsets of farmland birds were positively associated with AES for management of permanent pastures, and bird abundance was associated to habitat elements managed for the maintenance of nature and cultural values (e.g. old buildings, infield non-crop islands, stone walls and ditches). Farmland bird abundance was also positively associated with the amount of grasslands (leys and especially pastures) and set-aside without subsidies, whereas neither richness nor abundance was positively associated with the amount of organic fields at the local scale (i.e. within a 250 m radius). However, bird diversity was related to increased area of organic fields at the landscape scale (i.e. 25 km2); with a positive relationship in the most simplified landscapes but a negative relationship in more complex landscapes (i.e. with less arable land and more woodlands). Our results show that AESs are targeting habitats and habitat elements of high farmland bird diversity with the possible exception of organic farming in less simplified landscapes. Future studies investigating effects of AES management need to collect longitudinal before–after data on the change of biodiversity and need to investigate the possible landscape-dependent outcomes of specific management tied to AESs.

Farmland biodiversity continues to decline because changes in modern agriculture have led to the degradation and loss of key habitats. One farmland habitat that has received little attention during development of conservation measures is farmsteads. We use bird count data from a survey conducted at over 600 sites in 3725 km 2 agricultural landscapes in southern Sweden to investigate the importance of farmsteads as potential sources of biodiversity in simplified landscapes. We found that farmsteads, on average, had more bird species and individuals than semi-natural pastures and infield infield non-crop islands, probably due to a larger area of non-field habitats at farmstead sites. Presence of farm animals was an important predictor of bird diversity and numbers at farmsteads while variables associated with arable land-use intensification had limited effect. Old farmsteads with no current active farming, on average, had low bird numbers. We found no effect of agricultural intensification at the landscape level on alpha diversity at farmstead sites. Rather, species richness and abundance of birds tended to increase as landscapes became characterized by more intensive agriculture with larger fields. Farmsteads are widespread in simplified agricultural landscapes and may provide habitat to a range of farmland species. Applying conservation measures to farmsteads and local surroundings that increase the availability of safe nest-sites and good foraging grounds for birds could be implemented through publicity driven schemes. This combined with other agri-environment schemes in the surrounding landscape could enhance the amount of critical resources for farmland birds.

James A. Mills et al.-- Letter.

As the world's population continues to grow, the demand for food, fodder, fibre and bioenergy will increase. In Europe, the Common Agricultural Policy (CAP) has driven the intensification of agriculture, promoting the simplification and specialization of agroecosystems through the decline in landscape heterogeneity, the increased use of chemicals per unit area, and the abandonment of less fertile areas. In combination, these processes have eroded the quantity and quality of habitat for many plants and animals, and hence decreased biodiversity and the abundance of species across a hierarchy of trophic levels and spatial scales within Europe. This biodiversity loss has led to profound changes in the functioning of European agroecosystems over the last 50 years. Here, we synthesize the findings from a large-scale pan-European investigation of the combined effects of agricultural intensification on a range of agroecosystem services. These include (1) the persistence of high conservation value species; (2) the level of biological control of agricultural pests and (3) the functional diversity of a number of taxonomic groups, including birds, beetles and arable weeds. The study encompasses a gradient of geography-bioclimate and agricultural intensification that enables the large-scale measurement of ecological impacts of agricultural intensification across European agroecosystems. We provide an overview of the role of the CAP as a driver of agricultural intensification in the European Union, and we demonstrate compelling negative relationships between the application of pesticides and the various components of biodiversity studied on a pan-European scale.

Explanations for causes of farmland biodiversity declines often assume no spatial or temporal variation in the effects of land use on species abundance and performance. For example, European populations of skylark are assumed to have declined partly due to the switch from spring sown to autumn sown crops. Still, land use preferences of farmland birds may vary with region, landscape structure and time in the breeding season. We inventoried 430 transects in 36 landscape plots (each 25 km2) in three major agricultural regions of southern Sweden and show that land use-specific densities of skylarks display strong temporal and regional differences. Pre-nesting densities in late April–early May were highest in autumn sown cereals and other arable land use with vegetation, but decreased during the course of the breeding season such that densities in spring sown cereals were slightly higher than those in autumn sown cereals late in the season. This temporal shift in crop-specific densities of skylarks differed between regions. Temporal patterns of crop-specific densities of skylarks could be explained in terms of vegetation-dependent nest predation risk and foraging conditions. We suggest that land use preferences of farmland birds often could be expected to display a temporal and spatial variation and this should be reflected in a more flexible, context-dependent approach for the conservation of farmland biodiversity.

Summary 1. Because habitats have profound effects on individual fitness, there is strong selection for improving the choice of breeding habitat. One possible mechanism is for individuals to use public information when prospecting future breeding sites; however, to our knowledge, no study has shown prospecting behaviour to be directly linked to subsequent choice of breeding site and future reproductive success. 2. We collected long-term data on territory-specific prospecting behaviour and subsequent breeding in the short-lived northern wheatear (Oenanthe oenanthe). Non-breeders established prospecting territories (

The switch from spring-sown to autumn-sown cereals and the loss of habitat heterogeneity are often suggested to be key drivers of breeding bird decline on arable farmland. Yet, both factors are interlinked and it remains uncertain whether autumn-sown cereals reduce breeding bird numbers also in the structurally complex arable farmland of northern Europe. We tested whether autumn-sowing of cereals at both local and landscape scales affected the breeding bird community in a heterogeneous agricultural landscape of south-central Sweden. Rotation between sowing types was used as a semi-experiment based on 34 spring- vs. 41 autumn-sown cereal plots centred on infield non-crop islands of similar structure, size and surroundings. Species richness and territory abundance of ground-foraging species were significantly lower in autumn- than in spring-sown cereal plots both in the crop fields and the infield non-crop islands during the breeding season. No such effect was observed among foliage gleaning birds. Species richness in spring-sown cereal plots was less the more autumn-sown crops in the surrounding landscape within a 500 m radius. Average skylark densities did not differ between autumn- and spring-sown cereal plots because habitat preferences changed; densities declined in autumn-sown cereals during the growing season whereas they increased on spring-sown fields which had shorter swards throughout the breeding season. Our results indicate that negative effects of autumn-sown crops on breeding bird numbers spill over into both neighbouring non-crop and crop habitats. We conclude that agri-environmental schemes should place more emphasis on facilitating the value of the cropped area of fields as a foraging and nesting habitat. The retention of various non-crop habitats alone may not provide sufficient food close to nest sites for farmland birds that rely on crop fields for foraging.

Species monitoring is one key approach to assess human impact on nature. Four main approaches have been applied in bird monitoring: comparing distribution atlases from different times, repeated monitoring programmes, checklist programmes, and species-specific surveys. We evaluate the potential of another type of data for monitoring: presence-only data on species sightings reported voluntarily by the public to open-access internet platforms, here the Species Gateway (SG) in Sweden. We regressed data on the 242 bird species observed 2001–2009 in the Swedish Bird Survey (SBS) against the corresponding SG data. We also investigated the relationship for groups of species utilizing different habitats and displaying a significant inter-annual variation, a coefficient of variation >0.3 according to the SBS. We found support for a positive relationship in inter-annual variation in population level between the two datasets. However, the species subsets displayed variation from positive to negative correlations. Restricting the analysis to species with high inter-annual variation increased the positive correlation between the data sets. The reason for the mismatch between the two datasets may be explained by temporal changes in the willingness to report certain common species to the SG. Another reason may be an imbalance in the coverage of common versus uncommon species among the two datasets. The use of voluntary citizen-based data requires great care and good knowledge of the limitation of the data. If these requirements are fulfilled, we suggest that they may be a complement to standardised programmes, especially for assessing uncommon species of conservation concern.

1. Organic farming in Europe has been shown to enhance biodiversity locally, but potential interactions with the surrounding landscape and the potential effects on ecosystem services are less well known. 2. In cereal fields on 153 farms in five European regions, we examined how the species richness and abundance of wild plants, ground beetles and breeding birds, and the biological control potential of the area, were affected by organic and conventional farming, and how these effects were modified by landscape complexity (percentage of arable crops within 1000 m of the study plots). Information on biodiversity was gathered from vegetation plots, pitfall traps and by bird territory mapping. The biological control potential was measured as the percentage of glued, live aphids removed from plastic labels exposed in cereal fields for 24 h. 3. Predation on aphids was highest in organic fields in complex landscapes, and declined with increasing landscape homogeneity. The biological control potential in conventional fields was not affected by landscape complexity, and in homogenous landscapes it was higher in conventional fields than in organic fields, as indicated by an interaction between farming practice and landscape complexity. 4. A simplification of the landscape, from 20% to 100% arable land, reduced plant species richness by about 16% and cover by 14% in organic fields, and 33% and 5·5% in conventional fields. For birds, landscape simplification reduced species richness and abundance by 34% and 32% in organic fields and by 45·5% and 39% in conventional fields. Ground beetles were more abundant in simple landscapes, but were unaffected by farming practice. 5. Synthesis and applications. This Europe-wide study shows that organic farming enhanced the biodiversity of plants and birds in all landscapes, but only improved the potential for biological control in heterogeneous landscapes. These mixed results stress the importance of taking both local management and regional landscape complexity into consideration when developing future agri-environment schemes, and suggest that local-regional interactions may affect other ecosystem services and functions. This study also shows that it is not enough to design and monitor agri-environment schemes on the basis of biodiversity, but that ecosystem services should be considered too.

Ecological Applications 21. 5 (2011): 1772-1781 copyright by the Ecological Society of America, Effects of agricultural intensification (AI) on biodiversity are often assessed on the plot scale, although processes determining diversity also operate on larger spatial scales. Here, we analyzed the diversity of vascular plants, carabid beetles, and birds in agricultural landscapes in cereal crop fields at the field (n=1350), farm (n=270), and European-region (n= 9) scale. We partitioned diversity into its additive components α, β, and γ, and assessed the relative contribution of β diversity to total species richness at each spatial scale. AI was determined using pesticide and fertilizer inputs, as well as tillage operations and categorized into low, medium, and high levels. As AI was not significantly related to landscape complexity, we could disentangle potential AI effects on local vs. landscape community homogenization. AI negatively affected the species richness of plants and birds, but not carabid beetles, at all spatial scales. Hence, local AI was closely correlated to β diversity on larger scales up to the farm and region level, and thereby was an indicator of farm-and region-wide biodiversity losses. At the scale of farms (12.83-20.52%) and regions (68.34-80.18%), β diversity accounted for the major part of the total species richness for all three taxa, indicating great dissimilarity in environmental conditions on larger spatial scales. For plants, relative importance of a diversity decreased with AI, while relative importance of β diversity on the farm scale increased with AI for carabids and birds. Hence, and in contrast to our expectations, AI does not necessarily homogenize local communities, presumably due to the heterogeneity of farming practices. In conclusion, a more detailed understanding of AI effects on diversity patterns of various taxa and at multiple spatial scales would contribute to more efficient agrienvironmental schemes in agroecosystems, We also thank the European Science Foundation and the connected eight national science foundations for funding the presented study through the Eurodiversity AGRIPOPES (agricultural policy-induced landscape changes: effects on biodiversity and ecosystem services) program and the biology program BIOPLEX of the German Federal Ministry of Education and Science (BMBF)

It has been suggested that an increase in the area of low-intensity land-use on arable land (e.g. set-aside fields and short-rotation coppice), and high or increased farmland habitat heterogeneity, may halt or reverse the observed population decline of farmland birds. We tested these hypotheses by undertaking farmland bird censuses during two contrasting periods of agricultural policies and land-use (i.e. 1994 and 2004) in a farmland region covering a gradient of forest- to farmland-dominated landscapes in Sweden. Local species richness (i.e. at 3 hectare sites) declined significantly between 1994 and 2004. Local species richness was positively related to habitat heterogeneity in both years of study whereas temporal change in species richness was not. Local change in species richness was positively associated with a change in the proportion of non-rotational set aside and short-rotation coppice (i.e. low-intensity land-use forms), but also to changes in the amount of spring-sown crops. However, the effect of low-intensity land-use was significantly dependent on the amount of forest in the surrounding landscape. An increase in low-intensity land-use was linked to an increase (or less marked decrease) in species richness at sites located in open farmland surroundings but to a decrease in richness at sites located in forest surroundings. This interaction between amount of forest and low-intensity land-use could be interpreted as a “rare habitat effect”, where an increase in a farmland habitat only positively affects biodiversity when it was originally uncommon (i.e. open farmland areas). Our results suggest that conservation measures of farmland biodiversity have to be put in a landscape context.

1. Adult survival rates strongly affect population growth, but few studies have quantified if and why adult survival differs between breeding habitats. We investigated potential causes of habitat-specific adult survival rates for male and female northern wheatears (Oenanthe oenanthe L.) breeding in Swedish farmland. 2. We used multistate mark-recapture models based on 1263 breeding records between 1993 and 2007 to estimate survival rates based on habitat-type (SHORT vs. TALL ground vegetation) and breeding-success state parameters. We also used breeding-season observations from 2002 to 2007 and an experimental manipulation of ground vegetation height to identify factors influencing adult mortality. 3. Females had lower annual survival than males (0.42 +/- 0.02 vs. 0.50 +/- 0.02); this difference largely resulted from low female survival in TALL habitats because of higher nest-predation risk and the large proportion of adult females being killed on the nest (>20%) during nest predation events. 4. Among successful breeders, both sexes displayed similar survival rates, but survival was lower for breeders in TALL as compared to SHORT habitats (0.43 +/- 0.03 vs. 0.51 +/- 0.02). Experimental manipulation of ground vegetation height, controlling for individual and territory quality (n = 132), suggested the cost of rearing young to be higher in TALL habitats (survival of successful breeders in TALL vs. SHORT; 0.43 +/- 0.11 vs. 0.57 +/- 0.05). 5. Detailed observations of food provisioning behaviour during chick rearing revealed a habitat-related difference in parental workload corresponding to the observed habitat differences in adult survival for successful breeders. Adults breeding in TALL habitats were forced to forage further from the nest relative to SHORT-habitat breeders (mean +/- SE; 69 +/- 10 vs. 21 +/- 2 m), which increased the estimated daily workload for adults in TALL vs. SHORT habitats by c. 20%. 6. On-nest predation and parental workload during chick rearing combine to largely explain habitat-specific adult survival rates. The results have implications for our understanding of adult sex ratios, causes of source-sink demography and habitat-specific growth rates. Furthermore, it suggests SHORT field margins and other residual habitat elements to be important for the conservation of farmland passerines breeding in cropland plains.

We have assessed the population trends for the 255 bird species breeding in Sweden (including distinct subspecies), based on data for the last 30 and 10 years, respectively. Over the past 30 years more species have decreased (38%) than increased (32%) in numbers. In particular, formerly common farmland species have fared poorly but this is also true for some forest species. Over the past 10 years there are more species with increasing trends (29%) than there are species with decreasing trends (19%). Trends for several species in long-term decline have levelled off and have in some cases even started to increase. It is not known whether this recent change is a result of conservation efforts or simply that population numbers have stabilised at lower levels now permitted by the environment. It is therefore essential to initiate research devoted to finding factors directly linked to ongoing population changes, particularly for species in long-term decline. To cover population trends for all Swedish species additional monitoring programmes are needed, in particular on owls and in mountain habitats.

This study examines the importance of avian incubation costs as determinants of clutch-size variation by performing clutch-size and brood-size manipulations in the same population of Collared Flycatchers Ficedula albicollis during the same breeding season. In 2 5 cases when three or more clutches of the same size were completed on the same day, we moved two eggs on the day after the last egg had been laid from one randomly selected clutch (C) to another (C) and moved two other eggs from this to a third clutch (C+). In 20 other cases of simultaneously completed clutches of the same size, we moved two randomly selected young from one brood to a second and from that moved two other young to a third (B, B and B+groups). Most females were weighed the day after completion of the clutch and 1–4 days before hatching of the young, and some of them also 10–14 days after hatching of the young. We measured the daily energy expenditure of females incubating manipulated clutches of 4, 6 and 8 eggs by means of the doubly-labelled water (D218O) technique and also recorded their nest attendance. Hatching success of fertilized eggs was reduced in the enlarged clutches compared with control and reduced clutches. Females expired on average 3142.6 ml CO2 and expended 78.6 kJ per day while incubating, which corresponds to a metabolic intensity of 3.3 times BMR. Daily energy expenditure increased with clutch-size due to higher costs while incubating, and not because of changed activity patterns. There were no significant differences in length of incubation, female mass or mass changes between phases for the C, C and C+groups. In both the C and B groups, enlarged broods produced significantly more fledged young than control broods, and those significantly more than reduced broods. Fledgling tarsus-length and mass did not differ significantly between treatments in either the C or B groups. There was no significant difference in breeding success between clutch and brood manipulations. In this season, incubation costs did not entail significant fitness losses, expressed either as fledgling production or female condition. Also, control females could have raised more young to fledging age than they did with no apparent costs.

The diurnal pattern of foraging behaviour in birds is commonly linked to the risk of starvation and predation. During the breeding season, when offspring place additional demands on the quantity of food adults need to collect, diurnal foraging patterns may be influenced to a greater extent by food availability because adults need to balance starvation-predation risks not only for themselves but also their offspring. We used data-loggers to measure diurnal variation in rates of nest visits to 7- to 10-day-old nestlings of the insectivorous Northern Wheatear Oenanthe oenanthe in Swedish farmland habitat. Adults provisioned the nestlings with food for an average 19.5 h each day (n = 11 pairs), with visitation rates sharply increasing during the morning, remaining relatively stable between 0800 and 1700 hours, and then declining in the evening. This pattern is similar to daily temperature fluctuations and is consistent with the hypothesis that nest visit rates are a function of temperature-dependent prey availability. Higher rates of nest visits on warm days support this correlation between temperature and offspring feeding. However, without data on the rate of self-feeding by adults it is difficult to distinguish between patterns of nest visits being driven by food availability, or starvation-predation constraints being imposed on the parents; thus, future studies of patterns of offspring feeding should collect data on the self-feeding behaviour of the adults.

1. The widespread declines of farmland birds have generally been linked to agricultural intensification. We tested the hypotheses that (i) changes in agricultural policy, through its effects on agricultural intensification and (ii) regional differences in agricultural intensification affect temporal and spatial population trends of farmland birds in Sweden. 2. We analysed regional bird population trends (1976–2003) for seven common farmland bird species: the migratory lapwing Vanellus vanellus, skylark Alauda arvensis, starling Sturnus vulgaris and linnet Carduelis cannabina and the resident tree sparrow Passer montanus, house sparrow P. domesticus and yellowhammer Emberiza citrinella. We identified three periods of agricultural policy in Sweden between 1976 and 2003: the intensification period (i.e. 1976–87; promoting increased production), the set-aside period (1987–95; promoting extensification of farming) and the Common Agricultural Policy (CAP) period (1995–2003; promoting increased production). Population trends were compared between three types of Swedish farmlands: open plains (intensive farming with a marked intensification), mosaic farmlands (i.e. farmland-dominated forest mosaics, less intensive farming, but show moderate intensification) and forest regions (i.e. forest-dominated farmlands with low intensity farming and extensification/abandonment). 3. The four migrants displayed clear significant trend switches between the policy periods, with declines in the ‘intensification period’ and the ‘CAP period’ and less negative or even positive population trends in the ‘set-aside period’. The population trends of the three resident species showed no clear pattern in relation to agricultural policy periods. 4. All species except tree sparrow displayed significantly different population trends between farmland regions. Four species (lapwing, skylark, linnet and house sparrow) declined most in the open plains and the forest regions, whereas two species (starling and yellowhammer) declined most in the mosaic farmlands. 5. Synthesis and applications. Large-scale changes in agriculture policy have a strong potential to change the present poor state of farmland biodiversity as shown by the generally positive population trends in the ‘set-aside period’. It also suggests extensification to be beneficial to farmland birds. However, in regions of low profitability and an already ongoing extensification, a further extensification will lead to loss of both farmland habitat and bird diversity. In such regions mixed farming needs to be retained and hence should be supported.

Ecological traps are poor quality habitats that are preferred by individuals and that cause standard indicators of habitat quality (e.g., density, age structure, order of settlement) to be misleading. A maladaptive choice of habitats may have detrimental effects on individual fitness and long-term population persistence. For conservation purposes, it is therefore critical to identify ecological traps. We discuss a recent review on the relationships between density, reproductive success and productivity at the patch level. We also discuss the concept of ecological traps and definitions of habitat quality and habitat preference. Based on recent literature on ecological traps, we argue that no study shows evidence of an ecological trap in its strict sense, i.e., a preference for sink and an avoidance of source habitat. This lack of evidence is partly due to poor measures of preference and individual fitness, and to an absence of studies at the individual level. We suggest a two-step protocol at the level of individuals to investigate ecological traps by linking: (1) habitat characteristics, i.e., potential cues used by individuals, to fitness, and (2) preference for specific habitat characteristics. This protocol is illustrated by a long-term study on breeding territory selection in Northern Wheatears (Oenanthe oenanthe) in Sweden. Using our protocol, we could determine at least in part why Wheatears show a mismatch between habitat preference and fitness. We conclude that there is an urgent need for more studies on individual habitat-selection decisions before we can find less labour-intensive ways to identify potential trap situations.

The selection of breeding sites in heterogeneous habitats should ideally be based on cues closely reflecting habitat quality and thus predicting realized individual fitness. Using long-term population data and data on territory establishment of male Northern Wheatears (Oenanthe oenanthe), we examined whether territory characteristics linked to individual fitness (reproductive performance and survival) also were linked to territory preference. Breeding territories varied in their physical characteristics and their potential effects on reproductive performance, and this variation among territories was correlated from one year to the next. Of all measured territory characteristics (from the focal and the previous year) only territory field layer height predicted individual fitness, i.e., reproductive performance was higher in territories with permanently short rather than growing field layers. Territory preference, instead, was only linked to the size of territory aggregations, i.e., males settled earlier at territory sites sharing borders with several adjacent sites than at those with few or no adjacent sites. This mismatch between territory characteristics linked to fitness and those linked to territory preference was not explained by site fidelity or compensated for by the different fitness components measured. Because the results were not in agreement with an ecological trap scenario, where poor habitats are preferred over high-quality habitats, our results suggest a more general case of nonideal habitat selection. Whereas nonideal selection with respect to territory field layer height may be explained by its poor temporal predictability within the breeding season, the preference for territory aggregations is still open to alternative adaptive explanations. Our study suggests that nonideal habitat selection should be investigated by direct estimates of preferences (e.g., order of territory establishment) and their links to habitat characteristics and fitness components. Furthermore, we suggest that the probability of establishing a territory needs to be included as a factor influencing patterns of habitat selection.

Changes in agricultural policies have caused dramatic changes in land-use in agricultural landscapes. To investigate whether such changes in land-use relate to temporal changes in bird communities a repeated inventory (1994 and 2004) of farmland birds was made in 212 point-count sites in south-central Sweden.Distinct changes in abundance of several species over the study period were recorded, abundance of the 16 studied species decreased by 23%. The decline was significant for eight species, while two species increased significantly. Persistence and colonisation models suggested similar species-habitat relationships as the snapshot models, i.e. eight of the 12 associations were in line with what could be expected from the snapshot models. Occurrence of nine species was linked to land-use whereas six species displayed links between changes in occurrence and changes in land-use. In line with previous studies positive effects of short rotation coppice and negative effects of autumn-sown crops were found, while set-asides showed fewer effects than expected. In the snapshot models several species showed links to landscape characteristics such as amount of forest (negative for five species) and landscape heterogeneity (positive for six species). The evidence for effects of the landscape variables on persistence/colonisation was more restricted.The results suggest that both land-use changes and the landscape setting may cause local changes in abundance of farmland birds, even for species displaying a general decline in numbers between years, the effects of land-use changes being, however, strongly species specific. (C) 2014 Elsevier B.V. All rights reserved.

James A. Mills et al., The recent trend for journals to require open access to primary data included in publications has been embraced by many biologists, but has caused apprehension amongst researchers engaged in long-term ecological and evolutionary studies. A worldwide survey of 73 principal investigators (Pls) with long-term studies revealed positive attitudes towards sharing data with the agreement or involvement of the PI, and 93% of PIs have historically shared data. Only 8% were in favor of uncontrolled, open access to primary data while 63% expressed serious concern. We present here their viewpoint on an issue that can have non-trivial scientific consequences. We discuss potential costs of public data archiving and provide possible solutions to meet the needs of journals and researchers., C.T. was funded by the French Agence Nationale de la Recherche (grant ANR-12-ADAP-0006).

Studies, mainly from the UK, show that many farmland birds have declined as a result of recent agricultural intensification. We tested this idea by analysing farmland bird population trends in Sweden, a country displaying less dramatic agricultural changes and less intensive agriculture. Specifically we investigated whether (i) farmland specialists have declined more than generalists, (ii) population declines in Sweden are less marked than in England and (iii) Swedish population trends are associated with changes in the amount of autumn-sown crops, and inputs of pesticides and fertilizers. Data on population trends for 21 farmland bird species collected from the Swedish Breeding Bird Survey 1976-2001 were analysed in relation to agricultural changes in Sweden. Fifteen (71%) farmland bird species declined significantly in number (P < 0.05) over the 26 years. Farmland specialists displayed a significantly stronger average decline (55%) as a group than farmland generalists (7%). For seven species the declines were significantly steeper between 1976 and 1988 than between 1988 and 2001. Farmland bird populations have declined at least as much in Sweden as in England. Several specialist species displayed similar temporal patterns in population change in both countries. The area of autumn-sown crops has remained stable in Sweden, whereas use of pesticides and fertilizers has declined. There are no clear associations between these factors and observed farmland bird population declines. The similarities in bird population trends in Sweden and England, despite large differences in patterns of agricultural change in Sweden and England, may be explained by: (i) common wintering grounds, (ii) similar negative effects of agricultural intensification (England) and intensification/abandonment (Sweden) and (iii) a simultaneous loss of landscape heterogeneity. Synthesis and applications. Farmland birds in Sweden have declined by at least as much as in England, despite clear differences between the two countries in the degree of agricultural intensification over the last 30 years. We suggest that the marked declines in Swedish populations are caused by (i) the dual negative effects of intensification and abandonment of farmland at breeding grounds, and (ii) Swedish populations partly sharing wintering grounds with English populations. We conclude that agri-environmental schemes need to be flexible enough to address the negative effects both of intensification and the abandonment of farming. In addition, our results emphasize that farmland bird conservation is an issue without country borders. (Less)

Aim To examine temporal variation in nestedness and whether nestedness patterns predict colonization, extinction and turnover across islands and species. Location Dahlak Archipelago, Red Sea. Method The distributions of land birds on 17 islands were recorded in two periods 30 years apart. Species and islands were reordered in the Nestedness Temperature Calculator, software for assessing degrees of nestedness in communities. The occupancy probability of each cell, i.e. species–island combinations, was calculated in the nested matrix and an extinction curve (boundary line) was specified. We tested whether historical and current nested ranks of species and islands were correlated, whether there was a relationship between occupancy probability (based on the historical data) and number of extinctions or colonizations (regression analyses) and whether the boundary line could predict extinctions and colonizations (chi-square analyses). Results Historical and current nested ranks of islands and species were correlated but changes in occupancy patterns were common, particularly among bird species with intermediate incidence. Extinction and turnover of species were higher for small than large islands, and colonization was negatively related to isolation. As expected, colonizations were more frequent above than below the boundary line. Probability of extinction was highest at intermediate occupancy probability, giving a quadratic relationship between extinction and occupancy probability. Species turnover was related to the historical nested ranks of islands. Colonization was related negatively while extinction and occupancy turnover were related quadratically to historical nested ranks of species. Main conclusions Some patterns of the temporal dynamics agreed with expectations from nested patterns. However, the accuracy of the predictions may be confounded by regional dynamics and distributions of idiosyncratic, resource-limited species. It is therefore necessary to combine nestedness analysis with adequate knowledge of the causal factors and ecology of targeted species to gain insight into the temporal dynamics of assemblages and for nestedness analyses to be helpful in conservation planning.

Visiting breeding patches can allow prospecting individuals to gather information on local patch quality to make optimal decisions about selecting a breeding habitat in the following year. This prospecting behaviour has been described in many bird species. However, the nature of the information gathered by prospectors often remains unknown. We collected data on prospecting behaviour in the collared flycatcher, Ficedula albicollis , a small hole-nesting passerine bird, to investigate whether prospectors could gather information on their conspecifics' reproductive success, that is, ‘public information’. If they could, they would be expected to inspect conspecific nests, prospect at the time when public information is reliable, and be attracted to, and spend time at, successful sites. Prospecting at conspecific nests was frequent. Prospectors were mainly males, and prospecting activity closely matched the peak of nesting activity. The probability of observing a prospector at a nest increased with parental activity, measured by feeding rate and vigilance behaviour, but did not depend on direct measures of success of the inspected nest (nestling number and condition), or on female characteristics. Because feeding rate and vigilance behaviour were predictors of breeding success at fledging, prospectors were attracted to the most successful nests when cueing on conspicuous parental activity. Therefore, prospectors could gather accurate information on local conspecific reproductive success that may be used for breeding patch choice in the following year. We discuss alternative explanations for our results, and the need to test experimentally whether prospectors gather public information. We also discuss the role of breeding constraints on, and the origin of sex differences in, prospecting.

Availability and use of public information and conspecific density for settlement decisions in the collared flycatcher

Summary 1. Predation may be a strong selective factor affecting individual behaviour and life histories. However, few studies have investigated whether predators affect breeding habitat selection of prey species. 2. We tested whether breeding habitat selection and reproduction of a tropical migrant, the red-backed shrike ( Lanius collurio L.), was related to the presence of breeding pairs of its potential nest predators, magpie ( Pica pica L.), hooded crow ( Corvus corone cornix L.) and jackdaw ( C. monedula L.). 3. Only magpie and hooded crow territories were associated with an elevated risk of predation based on an artificial nest experiment with nests mimicking red-backed shrike nests. Predation risk on real red-backed shrike nests was also higher close to nests of hooded crow and magpie than elsewhere in the landscape. 4. Occupation frequency of known red-backed shrike territory sites during 3 years of study increased with increasing mean distance to the nearest magpie nest. 5. Changes in spatial distribution of corvids affected the spatial distribution of redbacked shrikes. Vacant red-backed shrike territory sites were more likely to become occupied in the next year when magpie and hooded crows had moved away from the site, while occupied sites were more likely to be abandoned in the next year when at least hooded crows had moved closer. 6. Our results suggest that breeding territories of nest predators may affect breeding habitat selection of prey species. Thus, a large part of an observed spatial dynamics of prey species may be caused by a corresponding spatial dynamics of predators. Because sink territories are occupied more irregularly than source territories, we suggest that the dynamics in predator sinks may be the driving force of the spatial dynamics of prey species.

Because habitat quality strongly affects individual fitness, understanding individual habitat selection strategies is fundamental for most aspects of the evolution and conservation of species. Several studies suggest that individuals gather public information, i.e. information derived from the reproductive performance of conspecifics, to assess and select habitats. However, the behavioural mechanisms of information gathering, i.e. prospecting, are largely unknown, despite the fact that they directly constrain individual selection strategies. To test whether prospectors gather public information or other cues of habitat quality, we manipulated brood size of collared flycatchers (Ficedula albicollis) and investigated subsequent attraction of prospectors. Experimentally adding two nestlings increased the probability of attracting prospectors to the nest as a result of increased parental feeding rates. Prospectors were attracted to the most successful sites because feeding rate predicted subsequent fledgling production. In the year following prospecting, individuals selected a breeding site very close to the prospected site. These results provide the first experimental evidence, to our knowledge, of the links between information gathering behaviour and breeding habitat selection strategies based on public information.

Highly ornamented males are often thought to be better able to provide females with resources, parental assistance, or good genes. Individual variation in such male abilities may override the costs of polygyny and therefore largely explain within-population variation in mating patterns. We investigated the influence of variation in male ornamentation and the environment on the costs of polygyny for female collared flycatchers (Ficedula albicollis), using data from a long-term study involving 2733 breeding attempts over 19 years. We show that females suffer reduced reproductive success when mated polygynously but that the costs of polygyny depend on an interaction between male ornamentation and timing of breeding. Among early breeders, polygynously mated females experience higher reproductive success when mated to less ornamented males, but among late breeders, females mated polygynously to highly ornamented males were more successful. We suggest that a high effort spent on obtaining extrapair matings early in the season renders highly ornamented males less able to assist two females in caring for the young. Thus, a male's ability to simultaneously gain from extrapair matings and polygyny may be limited through direct effects on female reproductive success. Given such limitation, extrapair matings may be expected to be less frequent in species with biparental care and a high level of social polygyny. Key words: collared flycatchers, extrapair mating, Ficedula abicollis, ornamentation, polygyny, timing of breeding.

Present knowledge of the effects of nest predation on spatial distribution, habitat selection and community structure of birds is to a large extent based on results from experiments with artificial nests. Although nest predation risk is likely to differ between artificial and real nests, most previous studies of nest predation using artificial nests have been lacking a proper control. We investigated whether predation rates on artificial nests predicted those on real nests by simultaneously comparing the fate of real and artificial nests (containing quail Coturnix coturnix and plasticine eggs) in 92 territories of the northern wheatear Oenanthe oenanthe in 1996. We also investigated whether risk for artificial nests was related to relative average risk for real nests in these territories (based on data collected two years before and two years after the experiment). Nest predation on artificial nests did predict relative predation risk for real nests only when quail egg depredation was used as the criterion for artificial nest predation. Despite plasticine egg depredation being the most common type of predation it was not associated with predation risk for real nests. Small mice and vole species dominated among cases with only plasticine egg depredation, while predatory mammals and snakes destroyed most quail eggs in artificial nests and most eggs in real wheatear nests. The results suggest that artificial nests may only predict the risk for real nests when the nest predator species are similar among the two types of nest. Furthermore, our data suggest that small mice and vole species rarely depredate nests of mid-sized passerine birds. Our results cast doubt on many previous conclusions based on experiments with artificial nests, since predation risk for such nests is likely to be uncorrelated with risk for real nests due to nest-type-specific differences in nest preying species.

Adverse weather conditions during parental care may have direct consequences for offspring production, but longer-term effects on juvenile and parental survival are less well known. We used long-term data on reproductive output, recruitment, and parental survival in northern wheatears (Oenanthe oenanthe) to investigate the effects of rainfall during parental care on fledging success, recruitment success (juvenile survival), and parental survival, and how these effects related to nestling age, breeding time, habitat quality, and parental nest visitation rates. While accounting for effects of temperature, fledging success was negatively related to rainfall (days > 10 mm) in the second half of the nestling period, with the magnitude of this effect being greater for breeding attempts early in the season. Recruitment success was, however, more sensitive to the number of rain days in the first half of the nestling period. Rainfall effects on parental survival differed between the sexes; males were more sensitive to rain during the nestling period than females. We demonstrate a probable mechanism driving the rainfall effects on reproductive output: Parental nest visitation rates decline with increasing amounts of daily rainfall, with this effect becoming stronger after consecutive rain days. Our study shows that rain during the nestling stage not only relates to fledging success but also has longer-term effects on recruitment and subsequent parental survival. Thus, if we want to understand or predict population responses to future climate change, we need to consider the potential impacts of changing rainfall patterns in addition to temperature, and how these will affect target species' vital rates.