By Sarah Mukherjee
Environment correspondent, BBC News
A lack of greenery may be responsible for the decline in sparrow populations
A new report suggests that modern garden design, urban development and paving over front gardens to use them as parking spaces could all be contributing to the catastrophic decline in the numbers of sparrows in our towns and cities.
Researchers say the study, by scientists from the RSPB, De Montfort University and Natural England, is the first to investigate the 20-year decline of house sparrows in suburbia.
But what does it take to create a sparrow friendly garden?
The sparrow used to be a familiar sight in our towns and cities, but within a generation, numbers have plummeted.
Researchers say numbers started falling in towns and cities in the mid-1980s. Cockney sparrows are almost non-existent, and the species has almost vanished from London.
House sparrows are also disappearing from Bristol, Edinburgh and Dublin.
One of the co-authors of the study, Dr Kate Vincent, describes it as "one of the most mysterious and complex declines of a species in recent years".
This new research studied house sparrows in Leicester and surrounding villages.
The birds declined by 28% during the three-year study - but scientists found that while sparrow chicks were hatching, they weren't surviving.
Dr Mark Avery, from the RSPB, says the research suggests that a lack of garden greenery means that the insects that sparrows rely on to feed their young are in short supply:
"When even the common sparrow is declining, it shows the world is in a bad state," he says.
"Massive changes in population can happen in a very short space of time, even in species that start off as very common. For example there were 9 billion passenger pigeons just 50 years before they became extinct."
One place that sparrows continue to thrive is in St Ives, Cambridgeshire - more particularly, in Will Peach's back garden.
But as the lead author of the new sparrow research, he admits that, if sparrows didn't thrive in his garden, it would be a rather worrying state of affairs.
He attributes his sparrow success to honeysuckle, and being a "useless, lazy gardener".
"Honeysuckle attracts loads of spiders and insects, which the sparrows love," he says, "and leaving vegetation to grow gives the right conditions".
It certainly seems to work - two sparrows are, as we speak, perching on a nearby tree looking at us inquisitively, and the air is melodious with birdsong.
So, now you have an excuse for doing nothing in the garden - you're helping one of Britain's best loved, and rapidly disappearing, birds.