Bye bye blackbird?: RSPB's Big Garden Birdwatch marks 40 years

World's biggest wildlife citizen survey maps changing fortunes of Britain's bird populations

The garden of 1979 was filled with glossy gangs of starlings, the atonal chirp of sparrows and the tap-tap of song thrushes breaking open snail shells.

In 2019, you're more likely to hear the screech of a ring-necked parakeet, the "coo" of a collared dove or the "woo" of a woodpigeon.