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The Common Agricultural Policy (CAP) of the European Union implements several farmland eco‐schemes, but most are considered ineffective in halting the population declines of farmland birds. Sown flower fields are among the few eco‐scheme types that rate as clearly beneficial. Yet, current CAP regulations lack minimum criteria for flower fields to qualify as eco‐scheme, and thus only partially exploit their potential biodiversity benefits.Earlier research on the attraction of farmland birds to different types of sown flower fields has focused on the breeding season. We know far less about relative use of these fields during the non‐breeding season, when food limitation can become severe. We therefore compared the attractiveness of four flower field types in SW Germany to 17 bird species during autumn and winter. Based on replicate surveys on 75–168 fields, we analysed bird incidences across these four types, and in relation to vegetation structure and landscape features.Flower field types showed little variation in species richness, but striking differences in selection by particular species. Finches and tits were disproportionally abundant on fields in their first year since sowing, buntings and whinchat on fields in later successional stages. Most flower fields established under CAP greening regulations were ploughed between September and November in their sowing year. Therefore, such fields fail to support farmland birds and other wildlife during a critical phase in their annual cycle.Birds were consistently more abundant on larger fields with a differentiated vegetation structure. Flower fields along hedgerows and groves primarily attracted inhabitants of woodland ecotones, while farmland birds had higher incidences on fields embedded in open landscapes.Policy implications. EU member states currently revise their regulations for farmland eco‐schemes, including sown flower fields. We propose minimum quality standards to assure that such fields effectively support farmland birds also during the non‐breeding season. Standards include a minimum maintenance for two years, more diversified seed mixtures, field sizes exceeding 12 m width or 0.18 ha area, and local diversity in flower field placement relative to other landscape elements such as hedgerows. [ABSTRACT FROM AUTHOR]

Proliferative kidney disease (PKD) caused by the myxozoan parasite Tetracapsuloides bryosalmonae is an emerging salmonid disease implicated in recent declines in salmonid populations. Laboratory experiments have shown that the clinical symptoms of PKD exacerbate with increasing temperature. However, empirical evidence for a relationship between climate change and PKD driven declines in wild salmonid stocks is scarce.The current study uses both empirical data and ecological niche modelling to extrapolate future changes in temperature and precipitation on the spread of PKD in relation to changes in suitability of rivers for its primary bryozoan and secondary salmonid hosts.A 20‐year dataset on brown trout density using standardised method shows a decline of more than 50% in the population of the river Wutach, south‐western Germany at 536–755 m elevation. The decline coincides with higher prevalence of PKD. This decline was temperature related and driven by reduced local survival of parr to yearlings. Kidney hyperplasia was highest at low elevations and correlated negatively with trout density.Niche models based on state‐wide data show strong overlap in the areas suitable for T. bryosalmonae and its primary bryozoan hosts, and a strong link with temperature. Projections based on moderate to high emission‐case climate change scenarios predict a 50%–82% decrease in the area suitable for salmonids within this century, linked to PKD.The empirical data identify temperature‐mediated PKD as the underlying cause of the population decline. This relationship was corroborated by the niche modelling results. The highest losses are expected in projected salmonid suitable areas where salmonid habitats currently overlap with areas suitable for T. bryosalmonae.With ongoing climate change, both current and future populations are at severe risk to T. bryosalmonae and its associated disease PKD. Conservation efforts of salmonid stocks are dependent on climate mitigation and measures to help salmonids adapt to the disease. [ABSTRACT FROM AUTHOR]

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