Contrasting population trends of Common Starlings (Sturnus vulgaris) across Europe

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Contrasting population trends of Common Starlings (Sturnus vulgaris) across Europe

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.Peer reviewe

Declining population trends of European mountain birds

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.Peer reviewe

Declining populations of European mountain birds

Mountain areas often hold special species communities and are thus in the high priority list of conservation. Changes in human land use, such as grazing pressure and afforestation, and especially in climate have been suggested as major threats for biodiversity in the mountain areas, because species have difficulties to find new suitable habitats in circumstances. Despite the special species communities very little is known about the population trends of species in mountain areas [1,2]. Here we studied population trends of 44 bird species in four major European mountain regions: Fennoscandia, UK upland, south-western (including Pyrenees) and south-central mountains (including Alps), covering 12 countries. We predicted that more species should show negative trends due to unfavourable environmental conditions. We also predicted the declines to be more severe in mountain specialists compared to mountain generalists, which are also found in the lowlands. We found in accordance with our predictions that mountain bird species have experienced significant declines (c. -7%) during 2002–2014. Mountain specialists showed a significant c. -10% decline in population numbers, and the slope for generalists was also negative but not significantly so. The slopes of specialists and generalists did not differ from each other. Fennoscandian and south-western populations were on average declining, but UK or south-central mountain birds showed on average stable situations. Our findings support the hypothesis that mountain species are declining. Thus more efforts should be undertaken to identify the causes of decline in order to protect these populations. [1] Lehikoinen, A., Green, M., Husby, M., Kålås, J. A. & Lindström, Å. 2014: Common montane birds are declining in northern Europe. Journal of Avian Biology 45: 3–14. [2] Scridel, D., Brambilla, M., Martin, K., Lehikoinen, A., Iemma, A., Anderle, M., Jähnig, S., Caprio, E., Bogliani, G., Pedrini, P., Rolando, A., Arlettaz, R. & Chamberlain, D. E.: The effect of climate change on holarctic mountain and upland birds: a review and meta-analysis. Ibis (in press).peerReviewe

Atrial signal amplitude predicts atrial high-rate episodes in implantable cardioverter defibrillator patients: Insights from a large database of remote monitoring trasmissions

Background: Parameters measured during implantable cardioverter defibrillator (ICD) implant also depend on bioelectrical properties of the myocardium. We aimed to explore their potential association with clinical outcomes in patients with single/dual-chamber ICD and cardiac resynchronization therapy defibrillator (CRT-D). Methods: In the framework of the Home Monitoring Expert Alliance, baseline electrical parameters for all implanted leads were compared by the occurrence of all-cause mortality, adjudicated ventricular arrhythmia (VA), and atrial high-rate episode lasting 6524\ua0hours (24\ua0h AHRE). Results: In a cohort of 2976 patients (58.1% ICD) with a median follow-up of 25\ua0months, event rates were 3.1/100 patient-years for all-cause mortality, 18.1/100 patient-years for VA, and 9.3/100 patient-years for 24\ua0h AHRE. At univariate analysis, baseline shock impedance was consistently lower in groups with events than without, with a 40\ua0\u3a9 cutoff that better identified high-risk patients. However, at multivariable analysis, the adjusted-hazard ratios (HRs) lost statistical significance for any endpoint. Baseline atrial sensing amplitude during sinus rhythm was lower in patients with 24\ua0h AHRE than in those without (2.45 [IQR: 1.65-3.85] vs 3.51 [IQR: 2.37-4.67]\ua0mV, P\ua01.5\ua0mV vs those with values 641.5\ua0mV was 0.52 (95% CI: 0.33-0.83), P\ua0=.006. Conclusions: Although lower baseline shock impedance was observed in patients with events, the association lost statistical significance at multivariable analysis. Conversely, low sinus rhythm atrial sensing ( 641.5\ua0mV) measured with standard transvenous leads could identify subjects at high risk of atrial arrhythmia