Farmland birds have declined in recent decades because of agricultural intensification, involving changes in cropping patterns, loss and deterioration of hedgerows and landscape simplification. Management to enhance farmland bird populations could aim to influence any of these, but which set of factors is the most important? A new study by the BTO and the University of Cambridge has investigated this question. Comprehensive statistical models were applied to BBS data to show that for most species, variation in abundance was best predicted by landscape structure, followed by field boundary composition and finally crop types in farmland-dominated BBS squares. This means that landscape features (such as the presence of woods, villages or the mixture of grass and arable farming) have the strongest influence on farmland bird populations. However, field boundaries and, especially, crops can be both changed more easily and have changed more over time than landscape features, and so have a key role to play in driving farmland bird population trends. This makes them realistic targets for management action, as well as potential sources of future conservation problems, although the extent of these effects will be constrained by the landscapes they are found in. Among the specific habitat influences tested, the presence of hedges with trees, which provide nesting habitat and song-posts, was shown to positively affect populations of several species, as did high levels of landscape and cropping heterogeneity. The latter boost habitat and resource variety, and therefore the number of individuals and species that can be supported. This study has important conservation implications because it shows the potential of different components of farmland management (such as national agri-environment schemes and the Common Agricultural Policy) to contribute to bird conservation. It also demonstrates the overriding importance of landscape structure in determining bird community composition, even within landscapes dominated by farmland.

The UK government is committed to establishing an ecologically coherent network of Marine Protected Areas (MPAs) to manage and conserve marine ecosystems. Seabirds are vital to such ecosystems, but until now these species have received little protection at sea. This is partly because there is scant information available on the oceanic regions they use at the different stages of their lifecycle. A new study led by the BTO, in partnership with the RSPB and Birdlife International, has sought to address this by bringing together work on how far UK-breeding seabirds travel from their colonies (typically in search of food for themselves or their chicks) during the breeding season. This study used results from tracking, indirect measures and survey-based observations of seabird movements to calculate ranges over which seabirds might forage. It also assessed the validity of these ranges based on the quality of the methods underpinning them. Manx Shearwater, Northern Gannet and Northern Fulmar had the largest maximum foraging ranges at 330, 590 and 580 km respectively, while Red-throated Diver (9 km) and Little Tern (11 km) had the smallest. The approach taken in this study can be used as a first step in identifying areas of ocean away from breeding colonies that may be crucial for sustaining seabirds. Further work would then be then required to firm up the boundaries of specific MPAs. This approach is however, relatively cheap and simple, and could easily be adopted outside the UK to become an important tool in protecting seabird habitat globally.