A nationwide survey of birds is being hailed as "a wake-up call" in the battle to protect the landscape.
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Stephanie Sim of the Royal Society for the Protection of Birds said that the 25th annual Big Garden Bird Watch drew the public's attention to their role in preserving their world.
"There is so much more we can do to live more harmoniously with wildlife and improve our quality of life at the same time," she said.
A celebrity chef from Northern Ireland is helping promote the watch which is the largest survey of its kind in the world.
Jenny Bristow will cook up treats for the birds in her garden as the RSPB calls on people to spend an hour recording the varieties of birds that they see.
"People are asked to observe the birds in their garden, a local park or simply out of their windows for an hour, and send their findings to the RSPB," said Ms Sim, the media and events officer for the society in Northern Ireland.
She said there was a serious point to the exercise.
"The results are compiled and used to see how our garden birds are fairing. Any decline in them signals a deterioration in the quality of our environment."
It was from surveys such as these that it became obvious that once common birds such as the starling and house sparrow were beginning to decline dramatically.
Declines in bird numbers indicate that the environment has less wildlife which may be a result of more pollution and poorer water and air quality.
"You can be sure that a wildlife garden that uses less pesticides and weed killers will have more birds. When we buy local and organic we are telling farmers that we value the fact that they farm in harmony with the land," Ms Sim said.
In the 2003 survey, the starling was recorded as the most common bird in Northern Ireland gardens. The house sparrow was in second place and was followed by the chaffinch, blue tit, greenfinch, blackbird, coal tit, great tit, robin and collared dove.
Those who wish to take part in the Big Garden Bird Watch can contact the RSPB Northern Ireland at 028 9049 1547 or log onto the website at www.rspb.org.uk/birdwatch.