23/03/2014 at 09:56
Ooh dear, how can I put this delicately? Dunnocks have rather peculiar mating habits! They indulge in polyandry (two boys one girl) or sometimes even the opposite! This means territorial brouhahas flare up. A reflection is enough to provoke a response. In addition (blushes) the female up-tails to 'present' to the male, who pecks at her until she is red and swollen, before mating. So persistent pecking at glass, or walloping into glass, are down to the birds' rather odd love life arrangements! Hey....but who are we to make judgements?