Rory has kindly allowed us to reproduce his dissertation abstract here and I'm sure he'd be happy for me to forward the whole thing to anyone who is interested.
Lowland farmland birds both in the UK and in Europe have declined since the 1970s,
resulting from post World War II agricultural intensification. As a result of these changes
in practices the Yellowhammer (Emberiza citrinella) population remains in decline. A
reduction in Over-winter survival derived from insufficient food resources is now thought
to be the most principle factor causing the demise of the Yellowhammer population in the
UK. In this study, data on winter foraging habits of the Yellowhammer in order to
establish the importance of supplementary feeding in a local population. Individuals were
recorded along line transects throughout December 2009 and January 2010 at
Brackenhurst estate, Southwell (England, UK). The results show that despite the presence
of semi natural habitats provided by the Environmental Stewardship Scheme (ESS) (e.g.
conservation headlands), the bird feeding station contained the highest frequency of
foraging yellowhammers than any other recorded habitat type. This study supports the
findings of Siriwardena et al. (2008) suggesting the ESS provides insufficient food
reserves through winter to reverse the decline of the Yellowhammer. Further research into
food availability throughout winter could provide information leading to the formulation
of new conservation measures which may not solely benefit the Yellowhammer but to
also other granivorous farmland birds currently in decline.