IT may seem surprising, but house sparrows are in trouble.
The RSPB's Sparrowatch survey has revealed that the birds are being seen in fewer and fewer West Yorkshire gardens.
As one of our more familiar birds, at home in our towns and cities, it is perhaps easy to think they will always be here.
But the latest study, coupled with surveys over recent years, have shown that their population has more than halved.
In urban areas, such as West Yorkshire, the decline has been even more dramatic.
Kirsten Whittaker, based at the RSPB's Denby Dale headquarters, said: "Putting out a handful of birdseed each day could hold the key to the survival of one of Yorkshire's most charismatic little birds.
"Our survey showed that the sparrows are far more likely to be seen in gardens where people put out food for the birds.
"In West Yorkshire, the average was 6.42 sparrows per home," she added.
"The results of the survey will help us to probe deeper into the exact problems facing this brilliant bird. Until the riddle is solved, it will be very tricky to reverse the bird's worrying decline."
There are many theories for the decline:
* The lack of food in the wider countryside, due to more efficient farming methods
* The lack of nest sites; modern buildings offer sparrows fewer opportunities
* Development of waste land may have reduced food availability
* The increased use of pesticides in the countryside and gardens may reduce the numbers of insects which sparrows need to feed their young.
* The birds are found across the world.
* Sparrows can live to the age of 12.
* They breed between May and July.
* Sparrows are also known as "spuggies" or "spadgers"
* The female lays between three and five eggs at a time.