A one hour walk in the sun around Fowlmere early morning wasn't helped by the blustery wind. A single Snipe was all I could find.
Edit (15/04/2010): Apparently females regularly 'beg' for food from males as part of their courtship. This must be what was happening. Still very early, but a bit more reasonable.
Edit (16/04/2010): The 'begging' (or rather 'demanding') behaviour only occurs in the later stages of courtship, once the female has been impregnated and requires extra food to supplement the developing eggs. So still a mystery!