Yesterday was Dawn Chorus Day. Birds sing in the dawn chorus to stake their claim to their territory and warn off others and to demonstrate their fitness as mates.  The peak time is around daybreak in late April and early May and the arrival of summer visitors and before they have young to care for.

I love to hear the different birds joining in song especially in spring although yesterday. after having had a sleepless night, I had to close the window because a blackbird was singing so loudly in the crab apple tree in the hedge opposite   Even so its song and those of skylarks, robins, chiffchaffs, yellow hammers, pigeons and many others were still audible.

I am fortunate to hear so many birds as the dawn chorus is hardly heard now in some places because of the declining bird population.  The UK has lost around a third of its wild birds in the last 50 years mainly due to changes in agricultural practices and land use.  Habitats have been destroyed and pesticides have caused a decline in insects for birds to feed upon.  The intensity and volume of bird song has declined as a result.
 This is a very interesting article.