Apparently between 1994 and 2007 Nightingale numbers dropped by 60% and its range shrank towards the South-east, with concentrations limited to Kent, Sussex, Essex, Suffolk and Norfolk.
Now a study by Chris Holt of the University of East Anglia suggests that this is because deer are eating the woodland undergrowth the birds need for nesting, a new study has shown.
It has been suspected this has been the case for some time and the prime culprit is the Muntjac. Muntjac are capable of breeding all the year round and have no natural enemies. Their browsing is causing major changes in the structure of woodland vegetation.
Mr Holt's research at Bradfield Woods in Suffolk found that the density of nightingales was 15 times greater in areas that were free of deer.