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1. In the North Sea, sandeels provide a vital food source for breeding seabirds, but are also the target of an industrial fishery. GPS tracking suggests that the most productive fishing grounds overlap with foraging areas of black-legged kittiwakes from eastern England, raising the prospect that the fishery could affect the birds. Rising sea temperatures also threaten sandeels, so kittiwake food supplies could be affected by local and larger-scale processes. 2. Drivers of kittiwake breeding success at Flamborough Head and Bempton Cliffs Special Protection Area, the UK's largest colony, and one of the closest to the sandeel fishing grounds, were examined. Relationships between sandeel stocks, sea surface temperature and kittiwake breeding success were analysed with generalized linear mixed models and generalized linear models, with model performance assessed using the Akaike Information Criterion and R². 3. Higher kittiwake breeding success was associated with higher sandeel spawning stock biomass (SSB; biomass of sexually mature fish) the preceding winter (R² = 21.5%) and lower sandeel fishing mortality two years previously (R² = 22.3%). After temporal trends were removed, only the fishing mortality effect remained. Models with multiple predictors supported the importance of fishing mortality. Higher sandeel SSB was associated with lower temperatures (R² = 15.2-38.6%) and lower sandeel fishing mortality (R² = 24.2-26.1%). 4. Hence, lower temperatures and fishing mortality were positively associated with sandeel biomass, and higher sandeel biomass and lower fishing mortality were positively associated with kittiwake productivity. In light of worsening environmental conditions and declining sandeel and kittiwake populations, careful consideration should be given to the requirements of sandeel-dependent predators when making fishery management decisions. [ABSTRACT FROM AUTHOR]

The cirl bunting ( Emberiza cirlus L.) has been the subject of targeted and successful conservation efforts based on agri-environment schemes ( AES) in the UK since 1993. Recent work has suggested that although focused on a single species, there have been wider biodiversity benefits for plants and some invertebrates., In this study we investigated whether a similar pattern could be found for the Auchenorrhyncha (plant- and leafhoppers) within agricultural grasslands, where they form an important component of the herbivore community., Sweep netting was used to sample Auchenorrhyncha from AES pastures, on which no pesticide or fertiliser inputs are allowed, and from conventionally grazed and cut (silage) fields at 25 locations in south Devon UK, during 2008., Generalised linear mixed models and non-metric multidimensional scaling were used to model abundance, species density, and community structure., AES fields had the highest abundance, followed by conventionally grazed and then cut fields. The same pattern occurred for species density, although there was no significant difference between conventionally grazed and cut fields. There was no difference in community structure between field types., Number of plant species, sward age, and nitrogen input were important covariates of field type, suggesting that the limitations on inputs resulting from AES are the likely drivers of the observed differences., The results add to the evidence base that suggests that increased agricultural intensity is inversely related to invertebrate biodiversity. They also provide evidence that AES designed for the cirl bunting have provided wider biodiversity benefits. [ABSTRACT FROM AUTHOR]