It is a sight that is never forgotten.

With its heart-shaped face, light brown body and large wings, a barn owl in flight is a majestic image.

Yet now, that sight is becoming increasingly rare. Following drastic habitat loss and extreme weather, the number of barn owls is at an all-time low.

It is widely reported that these iconic birds have declined by 70 per cent since the 1930s. Now conservationists believe that the run of bad winters has left the UK's population at the lowest it has ever been. The number of breeding pairs is thought by the Barn Owl Trust to be as low as 1,000.

Last year went on record as the worst year ever for barn owls. The prolonged snow and cold leading into March 2013 was particularly devastating and saw a 280 per cent rise in the numbers of dead birds reported to the British Ornithology Trust, just before the breeding season.

Habitats have also been eroded due to farming or development, and the use of chemicals such as rodenticides, which removes their food source, has added to their decline.

Dr Rob Stoneman, chief executive of Yorkshire Wildlife Trust (YWT) says: “One of the main reasons behind the decline is the widespread loss of grassland habitat and natural nesting sites. Since the end of the First World War 97 per cent of the UK's natural lowland grasslands have either been ploughed up or built upon. Barn owls have far fewer nesting sites due to tree loss and barn restoration.”

Now Yorkshire Wildlife Trust (YWT), which manages reserves and runs conservation projects across the county including in the Bradford district, is launching a bid to help save this native bird.

and ensure its long-term survival.

Earlier this year the trust launched an appeal to create and improve barn owl habitats on nature reserves, and work has started to create new areas of grassland feeding habitat. They are also working with developers converting barns, to install nesting boxes.

As part of this appeal it has launched a new website to gather sightings of barn owls across Yorkshire. Members of he public are encouraged to visit the site and use a simple mapping tool to record where and when they made their sighting. By creating this database the charity will be able to identify areas in which increased conservation effort will help to make a difference to barn owl populations .

The website will be used by the Trust's conservation staff to target areas for further grassland work and nest box installation over the forthcoming year.

In the Yorkshire Dales intensive sheep grazing keeps grass short, eliminating cover for small rodents, in particular voles, a main source of food for barn owls. “The conversion of stone barns, as well as barns falling into disrepair and being left without roofs has also impacted as barn owls don't like to get wet.”” says Lizzie Dealey, communications officer with YWT, “Last year's breeding year was the worst recorded in history. Heavy snowfall and very harsh conditions in the winter up to March 2013 resulted in a very high mortality rate.”

Flooding can also wipe out populations of small mammals, depriving the owl of food.

Road building has also led to fragmented habitats. “The owls can be hit by lorries when flying across roads,” says Lizzie. The installation of barriers such as screens beside roads to raise the level of their flight path could help, but are difficult to implement.

Les Barnett, president of Bradford Urban Wildlife Group, says: "Over the years we have seen a big change in farming practices coupled with changes in land use. A lot of farmland has been taken up by development, industry, housing and roads so the habitat potential has shrunk."

He adds: "In the Bradford district, in particular, we don't have a lot of farmland, so the land that is available is even more precious. People with even small areas of land need to be more considerate in they way they tend it. Within urban areas we see a lot of mown grass verges, lawns and golf courses. Everywhere you go there is mown grass. Often there is a lack of understanding as to the importance of uncut grassland for wildlife."

Yorkshire Wildlife Trust works with landowners and farmers, advising them on how to mange their land for wildlife. Adds Lizzie: “Many farmers have worked hard to leave alone field edges and put in hedgerows to provide cover for small mammals. And we are in the process of putting up nest boxes on farmers' land.

*Visit barnowls.ywt.org.uk