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Nomadic species can rely on unpredictable resources making them challenging to understand and, consequently, to conserve. Here, we present knowledge advancement for a nomadic predator, the Short‐eared Owl Asio flammeus, by tracking individuals from a wide latitudinal range inclusive of most breeding populations in western Europe (Iceland, Scotland and Spain). Tracked owls showed pronounced plasticity in both inter‐ and intra‐individual behaviour. Distances between sequential breeding areas of individual owls ranged from 41 to 4216 km, with similar low fidelity to areas used at other times of year. Owls spent most (> 60%) of their time occupying home‐ranges (including breeding) and least (< 10%) undertaking long‐distance movements. The propensity for long‐distance movements was least for the most geographically isolated population, Iceland. Annual survival rates of 47% were lower than expected for an owl of comparable body mass with mortality concentrated during long‐distance displacements and immediately after breeding. Extensive, nomadic travel to find areas where large broods might be reared may incur carry‐over costs that lower survival. Conservation planning and assessment for nomadic species and their habitats must acknowledge the uncertainties associated with nomadism at scales from local to international. [ABSTRACT FROM AUTHOR]

Mountain areas often hold special species communities, and they are high on the list of conservation concern. Global warming and changes in human land use, such as grazing pressure and afforestation, have been suggested to be major threats for biodiversity in the mountain areas, affecting species abundance and causing distribution shifts towards mountaintops. Population shifts towards poles and mountaintops have been documented in several areas, indicating that climate change is one of the key drivers of species' distribution changes. Despite the high conservation concern, relatively little is known about the population trends of species in mountain areas due to low accessibility and difficult working conditions. Thanks to the recent improvement of bird monitoring schemes around Europe, we can here report a first account of population trends of 44 bird species from four major European mountain regions: Fennoscandia, UK upland, south‐western (Iberia) and south‐central mountains (Alps), covering 12 countries. Overall, the mountain bird species declined significantly (−7%) during 2002–2014, which is similar to the declining rate in common birds in Europe during the same period. Mountain specialists showed a significant −10% decline in population numbers. The slope for mountain generalists was also negative, but not significantly so. The slopes of specialists and generalists did not differ from each other. Fennoscandian and Iberian populations were on average declining, while in United Kingdom and Alps, trends were nonsignificant. Temperature change or migratory behaviour was not significantly associated with regional population trends of species. Alpine habitats are highly vulnerable to climate change, and this is certainly one of the main drivers of mountain bird population trends. However, observed declines can also be partly linked with local land use practices. More efforts should be undertaken to identify the causes of decline and to increase conservation efforts for these populations. Overall populations of 44 mountain bird species declined significantly c. −7% in Europe (inc. Fennoscandia, UK upland, Alps and Iberia) during 2002–2014. Mountain specialists species, which occur only in the mountain areas in Europe, showed a significant −10% decline in population numbers. [ABSTRACT FROM AUTHOR]

CapsuleThe recent population decline of Whinchats has accelerated, including core breeding areas of Britain. Contrasting patterns of change with Stonechat suggest a large-scale environmental driver is affecting the entire Whinchat population. AimsTo explore broad geographical and landscape related differences in long-term patterns of population change in the Whinchat and Stonechat across Britain to identify candidate mechanisms of change. MethodsThe study uses 40 years of large-scale, long-term data from a series of three atlas studies to compare trends in range and abundance in Whinchats and Stonechats relative to landscape and weather variables. ResultsFor Whinchats there has been a long-term and accelerating decline in abundance, that includes stronghold areas of Britain. The Stonechat population has undergone a net gain in abundance with regional and altitudinal variations. These two very different patterns of change suggest the relative ubiquity of decline in Whinchats has a common source affecting the whole population. ConclusionsThe scale and magnitude of decline in Whinchats should stimulate a revision of the species conservation status in Britain, with renewed focus on studying the species' ecology across its breeding and winter range in order to determine the likely large-scale drivers of its decline. [ABSTRACT FROM PUBLISHER]

CapsuleThe total area encapsulated by the hunting ranges of breeding Short-eared OwlsAsio flammeuswas broadly similar between day and night and also through the season, but activity was concentrated more on lower altitude graminoid-dominated areas during daylight and early in the breeding season. AimsTo assess the representativeness of diurnal observations alone for determining ranging behaviour and habitat-use of breeding Short-eared Owls. MethodsThe diurnal and nocturnal ranging behaviours of four radiotagged Short-eared Owls were compared. Further diurnal field observations were used to assess the representativeness of the behaviour of the radiotagged birds. ResultsShort-eared Owls tended to hunt more over higher ground (where there was a greater ericaceous component within the moorland vegetation) at night and also later in the breeding season; the area of the total hunting range remained similar through the season (mean about 200 ha). Nocturnal activity rates closely matched those during peak diurnal activity periods. ConclusionDiurnal observations of breeding Short-eared Owls could provide representative data to inform breeding population densities and distribution but they may not be representative of overall habitat-use or ranging behaviour within home-ranges. Assessments of the risks to breeding Short-eared Owls of developments on moorland (e.g. forestry, wind turbine construction, grazing changes) based on diurnal observations alone may not reflect the true scale of potential impacts, which would also need to consider nocturnal behaviour. [ABSTRACT FROM PUBLISHER]

Capsule The likelihood of an area being occupied by breeding Whinchats was inversely related to altitude, and areas with south- and east-facing aspects were favoured over those with north- and west-facing aspects. Aims To identify habitat features and physical attributes of Whinchat territories in upland areas of the UK. Methods Comparison of habitat features and physical attributes measured at random points within territories and > 100 m from a territory in an area with a relatively high breeding density were used to identify factors associated with Whinchat occurrence in upland Scotland. Further data were extracted from recent independent surveys conducted elsewhere in upland Britain. Results Within a favoured habitat (young sparse shrubs and developing ground vegetation) in the main study site, the probability of an area with south- and east-facing aspects being occupied by breeding Whinchats exceeded 80% below 300 m asl and declined linearly to less than 20% above 500 m. For areas with north- and west-facing aspects, the probability of occupancy at 300 m was 40% and close to zero at 500 m. Territory size increased with altitude. Data from elsewhere in upland Britain supported an association of altitude and aspect with Whinchat territories but suggested that such environmental limitations differed between regions. Conclusion Within marginal uplands, Whinchats could be constrained at their lower altitudinal limit by intensive agricultural land-use and at their upper altitudinal limit by environmental restrictions on their breeding biology. Such limitations need to be considered if such areas are to continue to support viable populations of a declining and formerly widespread species. [ABSTRACT FROM AUTHOR]

The article examines the ranging behavior and habitat selection by three Hawfinches Coccothraustes coccothraustes in late winter on the grounds of Scone Palace, near Perth, Scotland. Monitoring of the two radio-tagged male Hawfinches indicated a range of 34.9 and 1.2 square kilometers, respectively while the female had a range of 1.4 square kilometers. The birds were located at several tree species, including Oak Quercus robur/petrea, Yew Taxus baccata, Sitka Spruce Picea sitchensis, Lime Tilia, Sycamore Acer pseudoplatanus and Fir Abies. Observation shows that Sitka Spruce and Cypress were used as roost sites.

Capsule The proportion of time during which breeding Short-eared Owls could be seen during daylight hours was low and assessment of seasonal variation in their detection likelihoods suggests that surveys may only be able reliably to identify pairs that successfully reach the chick-rearing stage. Aims To identify the most appropriate times of day and stages of breeding for surveying and to contribute towards the development of feasible survey protocols. Methods Fixed point watches sampled the activity of breeding Short-eared Owls in three extensive study areas in Scotland during two breeding seasons; 2006 and 2007. Results The proportion of time for which breeding owls were visible during daylight hours was low (4.8% of the time for the season March-July) and there was a statistically significant effect of stage of breeding and also of time of day within some stages of breeding on the proportion of time during which owls were visible. There was a greater than 75% likelihood of seeing owls during a combined total of four hours of watching (1) in the evenings during incubation (mid-April to mid-May), (2) mornings and evenings during chick-rearing (June), and (3) early morning and late evening during fledging (July). The likelihood of seeing key territorial behaviours was always low. The mean distance from an observer at which owls were first detected in 2006 was 495 m (95% CI: 390-601 m), and significantly greater in 2007 at 741 m (95% CI: 651-832 m). Conclusion The interpretation of field surveys of breeding Short-eared Owls should take into account the effect of season and time of day on the likelihood of detection. Surveys may only be able to reliably identify pairs that successfully reach the chick-rearing stage and, therefore, the most robust survey/monitoring unit may be pairs that successfully hatch young. Distances at which owls could be reliably detected suggest that a survey of any defined area will require vantage points separated by a minimum distance of about 1.5 km with allowance for topography and a 180° field of view. Evidence of a disturbance or deterrence effect of field surveyors on the owls supports the need for unobtrusive survey methods. [ABSTRACT FROM AUTHOR]