The RSPB big garden birdwatch begins
The wildlife charity the RSPB is appealing to the public to take part in its annual Big Garden Birdwatch.
With well over half a million people submitting their results in 2010, this is one of the the world's largest wildlife surveys.
It could reveal, says the RSPB, what effect a year of "confusing weather" has had on our garden birds.
The event will take place on 28 and 29 January. Participants can register and submit results on the RSPB website.
Carrying out the survey during the winter, when the birds rely more on supplementary feeding, allows the charity to build a representative "snapshot" of how healthy the populations are of our most familiar birds.
"Doing the survey in winter allows us to predict how birds are faring ahead of the breeding season," explained the RSPB's Sarah Houghton.
She said that the unpredictable weather over the last few months would make the results even more interesting.
"With plenty of natural food still about some of the usual suspects might be a bit elusive, but heavy rain and strong winds could send other surprises our way.
"And spring-like signs might even be inspiring early breeding activities.
"There's already been lots of evidence of birds recce-ing potential nest sites so whatever the weather, it'll be a busy time."
Birds that might start nesting early this year include blue tits, great tits and robins.
"Don't just watch your feeders; keep an eye on your nest boxes too," Ms Houghton said.
You do not actually need to have your own garden in order to take part. This year, shopping centres, retail parks and even hospitals are offering their outdoor spaces for people to join in the count.
Despite a relatively mild winter so far, the RSPB is encouraging people to feed their garden birds.
Wildlife adviser Val Osborne, said: "We are very mindful that a late cold snap could be a real shock for the birds but the food we all put out can make a real difference to see birds through the winter."
Mike Toms, head of garden ecology at the British Trust for Ornithology (BTO), praised the annual survey for "introducing people to the notion of 'citizen science'".
The BTO runs a year-round garden bird survey and hopes to recruit more participants as a direct result of the interest in this weekend's event.
The Big Garden Birdwatch started in 1979, as an activity for the RSPB's junior members. It opened up to adults and non-members in 2001.
Source: BBC Nature