Many doubt the benefits of over-wintered stubble for birds, as clean stubbles seem devoid of seed food. Indeed, BTO studies found that most stubbles were poorly used by birds. However, large congregations of farmland birds in the winter are most often associated with stubbles, unless there are seed crops available for them.
Last weekend, I was delighted to find corn buntings on my home patch during a BTO winter atlas survey. There were only two of them, but I was begining to think that we had lost them completely. I identified the square as the most likely contender for corn buntings in the whole area, given the very open nature of the farmland. When I visited the square (400 ha), there was just one large stubble field. Not only did it contain the two corn buntings, but also all of the yellowhammers in the square (50) and all of the skylarks (120). These were all congregated in one area of the field where seeding annual meadow grass was available.
All comes down to the preceeding management - I have a farmer using low input cereals preceeding an over winter stubble and one using the reduced herbicide cereal crop management preceeding over winter stubbles - both are hugely attractive to Corn buntings with the former attracting well over 140 individuals.
These do tend to be depleted by February at the latest, but having a good annual cereal heavy wild bird mix (left until late March or early April) is good in combination for this species.
Merry Christmas!