Skylarks have declined by 59% in the UK since 1970. Winter food availability on farmland is a critical welfare determinant, as skylarks depend on weed seeds and invertebrates on overwintered stubbles and field margins that are increasingly absent from modern farms.
Skylarks dependent on modern cereal farmland face food shortages in winter when invertebrates are unavailable and weed seeds have been depleted. Weight loss in cold spells rapidly becomes critical for small passerines. Nesting skylarks on rapidly-growing cereal crops face repeated nest failure as vegetation height increases beyond the tolerance threshold. The repeated energy cost of failed nesting attempts across a season represents significant welfare impact.