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Simple Summary: This article demonstrates the dampening of small mammal population dynamics and describes the numerical response of owls in Latvia. Numerical response was measured by diet, breeding performance, and trends in population change of six owl species. The responses varied among owl species, ranging from increased food niche breadth in more plastic species to reduced breeding performance and decreasing population size in more specialized species. The eagle owl seems to depend on voles in the previous autumn via the carry-over effect as measured by reduced breeding performance. Species more specialized in breeding in mature forests showed greater population declines, since mature forests are vital for owl breeding, as well as hold higher vole densities. Strong numerical and functional responses of owls to voles in cyclic environments are well known. However, there is insufficient knowledge from the boreonemoral region in particular, with depleted populations of small mammals. In this study, we describe the dynamics of the small mammal population in Latvia from 1991 to 2016 and link them to owl population characteristics. We used food niche breadth, number of fledglings, and population trends to lay out the numerical response of six owl species to dampened small mammal population cycles. We found temporarily increasing food niche breadth in tawny and Ural owls. There were no other responses in the tawny owl, whereas the breeding performance of three forest specialist species—pygmy, Tengmalm's, and Ural owls—corresponded to the vole crash years in Fennoscandia. Moreover, the populations of forest specialist owls decreased, and the change in the Ural owl population can be attributed to the depletion of small mammal populations. We found evidence of a carry-over effect in the eagle owl arising from a strong correlation of declining breeding performance with the small mammal abundance indices in the previous autumn. We conclude that dampening of the small mammal population cycles is an important covariate of the likely effects of habitat destruction that needs to be investigated further, with stronger responses in more specialized (to prey or habitat) species. [ABSTRACT FROM AUTHOR]

Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve conditions on poor-quality sites could be an effective approach, but only if local conditions consistently influence local demography and hence population trends. Using long-term measures of abundance and demography of breeding birds at survey sites across Europe, we show that co-occurring species with differing migration behaviours have similar directions of local population trends and magnitudes of productivity, but not survival rates. Targeted actions to boost local productivity within Europe, alongside large-scale (non-targeted) environmental protection across non-breeding ranges, could therefore help address the urgent need to halt migrant landbird declines. Such demographic routes to recovery are likely to be increasingly needed to address global wildlife declines. [ABSTRACT FROM AUTHOR]

The greatest loss of biodiversity in the EU has occurred on agricultural land. The Common Starling (Sturnus vulgaris) is one of the many numerous and widespread European farmland breeding bird species showing major population declines linked to European agricultural intensification. Here we present results based on monitoring data collected since 1975 in 24 countries to examine the influence of changing extent of grassland and cattle abundance (based on results of earlier studies showing the importance of lowland cattle grazed grassland for the species), wintering provenance and temperature on national breeding population trends of Starlings across Europe. Positive Starling population trends in Central-East Europe contrast with negative trends in North and West Europe. Based on this indicative approach, we found some support for the importance of cattle stock and no support for grassland, temperature or wintering provenance to explain Starling population trends in Europe. However, we acknowledge such a European-wide analysis may conceal regional differences in responses and suggest that currently accessible national land use datamight be insufficient to describe the detailed current changes in animal husbandry and grassland management that may be responsible for changes in food availability and hence breeding Starling abundance and their differences across Europe. Reviewing results from local studies relating Starling population trends to local agricultural change offer contradictory results, suggesting complex interacting processes at work. We recommend combining national datasets on demography, land-use/agricultural practices and from autecological research to better explain the reasons for contrasting Starling trends across Europe, to enable us to predict how changing agriculture will affect Starlings and potentially suggest mitigation measures to restore local populations where possible. [ABSTRACT FROM AUTHOR]

We surveyed themilitary training areaAdazi to evaluate the effects of disturbance caused by military activities on the abundance of protected bird species considered to benefit from disturbances at the site (SCBD).We collected data on the abundance of the selected bird species in a set of representative sample plots during three repeated surveys. In each plotwemapped areas affected by different visually detectable disturbances ofmilitary origin and areas covered by EU protected habitat types. Overall abundance and richness of SCBD were calculated for each of the surveyed squares. Generalised linear modelling was used to relate the recorded abundance of each species, and the overall abundance and richness of SCBD, with the available habitat and military disturbance parameters. We evaluated a set of competitive models to identify the most important explanatory variables. The modelling results imply clear positive effects of most of the military activities on the analysed species as well as overall species richness. The variables describing the availability of habitats alone could not explain as large variation in the data as together with the disturbance variables. The results show that the recent (up to one year) andmoderately recent (up to two years) disturbances were themost important tomaintain the habitats. The results suggest that these species tend to occupy the newly created suitable habitat patches in the next breeding season. At the time of the study, there was no measurable negative effect of the military activities on abundance and richness of the analysed species. However, some negative effects ofmilitary activities on species behaviour were observed. [ABSTRACT FROM AUTHOR]

Abstract: We studied the spatial connectedness of Natura 2000 site boundaries and the functional connectivity of the Natura 2000 network across the 34 terrestrial borders of the European Union. Connectivity was measured by the dispersal success of 192 reptile, amphibian, invertebrate and plant species from Annex II of the European Union Habitats Directive, based on the presence of same species on both sides of the borders. Connectedness and connectivity varied greatly between state borders, with good and bad examples found in all parts of the European Union. Connectedness and connectivity were positively correlated. However, a few outlying examples showed that good connectedness is not necessarily associated with good connectivity and that good connectivity is not always possible because of different habitats and/or different management on both sides of border. In 13 out of 34 borders the connectivity measure was 100% and in 11 other borders it was over 50%. Very few of the geographical and political factors tested to explain variation in connectedness and connectivity were significant. Better connectedness and connectivity, both at the border and site-pair level, was correlated with the rivers forming the border. The time since the designation of the second site in a site-pair was nearly significant, suggesting that connectivity might have always existed in nature but the ‘documentation of it’ required some time for additional site inventories. It seems that each country border has its own history with a unique subset of factors influencing Natura 2000 site selection and management thus generalising our findings to other international borders would be difficult. We did not find substantial differences in trans-boundary connectivity among taxonomic groups. The application of our method elsewhere in the World would perhaps bring interesting results at a large (continental or sub-continental) scale, provided that similar data are available. [Copyright &y& Elsevier]

• Species are often defined as either associated or not associated with a habitat. • Definitions for species' habitat specialization are also static and categorical. • Relative habitat use, RHU, provides a scalable, continuous alternative measure. • We show that RHU scores and literature classifications are generally well aligned. • RHU should be considered when defining species' habitat specialization. In order to understand species' sensitivity to habitat change, we must correctly determine if a species is associated with a habitat or not, and if it is associated, its degree of specialization for that habitat. However, definitions of species' habitat association and specialization are often static, categorical classifications that coarsely define species as either habitat specialists or generalists and can fail to account for potential temporal or spatial differences in association or specialization. In contrast, quantitative metrics can provide a more nuanced assessment, defining species' habitat associations and specialization along a continuous scale and accommodate for temporal or spatial variation, but these approaches are less widely used. Here we explore relative habitat use (RHU) as a metric for quantifying species' association with and degree of specialization for different habitat types. RHU determines the extent of a species' association with a given habitat by comparing its abundance in that habitat relative to its mean abundance across all other habitats. Using monitoring data for breeding birds across Europe from 1998 to 2017; we calculate RHU scores for 246 species for five habitat types and compared them to the literature-based classifications of their association with and specialization for each of these habitats. We also explored the temporal variation in species' RHU scores for each habitat and assessed how this varied according to association and degree of specialization. In general, species' RHU and literature-derived classifications were well aligned, as RHU scores for a given habitat increased in line with reported association and specialization. In addition, temporal variation in RHU scores were influenced by association and degree of specialization, with lower scores for those associated with, and those more specialized to, a given habitat. As a continuous metric, RHU allows a detailed assessment of species' association with and degree of specialization for different habitats that can be tailored to specific temporal and/or spatial requirements. It has the potential to be a valuable tool for identifying indicator species and in supporting the design, implementation and monitoring of conservation management actions. [ABSTRACT FROM AUTHOR]

In this article, we provide access to, and information on the production of 42 ecogeographical variables (EGVs) used to describe the landscape of Latvia at three scales (local and two landscape). Layers are focused on the description of forest heterogeneity, but account for other ecosystems and land cover types as well. The more temporarily changing land use and land cover (LULC) types as forest and agricultural lands are described from 2017 databases. With most of the other LULC information was gathered from the topographic map (2016) at the scale of 1:10 000. All the raster layers provided here are in the Latvian projected coordinate reference system (epsg:3059) with a grid cell size of 25 ha. Each layer provides quantitative information on the area, shape, and edge of habitat classes and additionally, age, time since the last forestry disturbance, relative soil humidity, relative soil richness etc. for forests. The three scales represent information from within 25 ha grid cell, and two radii - 1250 and 2500 m - around the centre of the grid cell., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)

Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve conditions on poor-quality sites could be an effective approach, but only if local conditions consistently influence local demography and hence population trends. Using long-term measures of abundance and demography of breeding birds at survey sites across Europe, we show that co-occurring species with differing migration behaviours have similar directions of local population trends and magnitudes of productivity, but not survival rates. Targeted actions to boost local productivity within Europe, alongside large-scale (non-targeted) environmental protection across non-breeding ranges, could therefore help address the urgent need to halt migrant landbird declines. Such demographic routes to recovery are likely to be increasingly needed to address global wildlife declines.