A recent study carried out by Anglian Water and the British Trust for Ornithology (BTO) has shown that a decline in nightingale numbers could be due to habitat changes in their migratory route to Africa.
By fitting a solar powered tracking device to 10 birds in Grafham Water, Cambridgeshire, last year, the device was able to determine where the birds were at any given time due to the electronic clock, calendar and light meter all contained in its 0.5g weight.
According to the BTO, numbers have dropped more than half since 1995 with only 6,000 singing males left in the UK. Their range is also shrinking and they are now only found predominantly in the South and East of England.
Seven birds made it back from the 3,000 mile journey through France, Spain, Gibraltar and along the African coast to The Gambia or Senegal. The journey took six weeks with the birds returning to breed in March, often to the same shrub they were on the previous year.
The data will be fully analysed by the Autumn but could hold many answers to their decline.