Ibis (2004), 146 (Suppl. 2), 155–162 © 2004 British Ornithologists’ Union Blackwell Publishing, Ltd. Sustainable Arable Farming For an Improved Environment (SAFFIE): managing winter wheat sward structure for Skylarks Alauda arvensis ANTONY J. MORRIS, 1 * JOHN M. HOLLAND, 2 BARBARA SMITH 2 & NAOMI E. JONES 3 1 The Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire SG19 2DL, UK 2 The Game Conservancy Trust, Fordingbridge, Hampshire SP6 1EF, UK 3 Central Science Laboratory, Sand Hutton, York YO41 1LZ, UK Research has shown a close correlation between the decline of the UK Skylark Alauda arven- sis population and the replacement of spring-sown cereals with winter-sown varieties, in which advanced sward development prevents successful multiple nesting attempts and reduces access for foraging. Widescale reversal of sowing times is unlikely for commercial reasons, so research has recently focused on ways of manipulating the sward structure of winter wheat to prolong access to nest-sites and food. An RSPB pilot study investigated leaving small ‘undrilled patches’ in otherwise conventionally managed winter wheat crops. This option was later incorporated into a fully replicated experimental design, as part of the Sustainable Arable Farming For an Improved Environment (SAFFIE) project. This large consortium-led project aims to test solutions for improving biodiversity within winter- cereal-dominated rotations. The experiment described here ran over 2002–3, with three field-scale ‘treatments’ on 15 sites in the first year. The treatments compare (1) conventional winter wheat, (2) winter wheat sown in double-normal width (25 cm) wide-spaced rows (WSR) and (3) winter wheat with two 4-m by 4-m undrilled patches per hectare (UP). Results from the 2002 breeding season showed that undrilled patch treatments supported more breeding Skylarks for longer, most likely by aiding accessibility of food. WSR rows were little used by Skylarks and did not improve the abundance of favoured seed and invertebrate food items over conventional crops. Nesting performance and foraging patterns are dis- cussed with reference to invertebrate food abundance and its accessibility, as determined by sward structure. In 2002, winter wheat crops were grown on over 2 million hectares of British farmland. In contrast, the area sown with all types of spring cereals was 600 000 ha. This figure represented an 80% decrease from the 1970 spring-sown total, compared with a decrease of just 13% in the total area of cereals grown. In some regions where soil conditions mean that spring cultivation is regarded as high risk, winter wheat may account for nearly 90% of all cereal crops (< 3.5% of which are spring sown) (Anon. 2002). The severe decline of 52% in the UK’s Skylark Alauda arvensis population between 1970 and 1999 (Gregory et al. 2003) has resulted in its listing as a UK Biodiversity Action Plan Priority Species. Skylark is also one of the 19 species of farmland birds that contribute to the UK Government’s Quality of Life breeding bird indictor. The government also has a Public Service Agreement to reverse the long-term decline in the number of farmland birds by 2020 (Gregory et al. 2004). Donald and Vickery (2000) identified a striking correlation between the replace- ment of spring-sown cereals with winter-sown varie- ties and the decline in Skylark abundance. The shift in sowing times is likely to have impacted on the Sky- larks via a number of different mechanisms. During winter, the loss of weedy stubbles (a key source of weed seed, spilt grain and invertebrate food) result- ing from winter sowing of cereals is likely to have been detrimental (Robinson 2001). There is also *Corresponding author. Email: tony.morris@rspb.org.uk