Like so many of nature's beautiful creatures, the Eastern bluebird's erstwhile thriving existence in Bermuda has been under siege for a long time, thanks to man's over-development of the land, his use of pesticides, plus a variety of introduced predators, including the common sparrow.

So endangered had the bluebird become, in fact, that if it weren't for the concerted efforts of so many dedicated people, including conservationists, Tommy Outerbridge and the former Bluebird Society, and the Bermuda Audubon Society, the species would have faced certain extinction here.

While these collective efforts have pulled the bluebird population back from the brink -- there are an estimated 500 birds flying around at present -- the battle is by no means won.

So it is that, with the nesting season now underway, the call is once more going out for all of Bermuda to get involved in its success.

Before detailing the appropriate ways in which to help, however, it is first necessary to understand the problems which threaten our bluebird population.

The Eastern bluebird (sialia sialia) is a native species to Bermuda, and the only location outside North America where the species breeds. It was here before the Island was first settled in 1609. The original landscape, with its forest growth and coastal grasslands, provided a perfect home, with old cedars and cliff cavities making perfect nesting sites. Non-avian predators were non-existent.

How very different from the past 50 years, when man and various predators have seriously impacted on everything from nesting sites to survival of the eggs and fledglings.

The Bermuda Audubon Society lists the chief offenders as: the vicious house sparrow, the European starling, the Great kiskadee, pesticides, rats, feral cats, tropical fowl mite, the cedar blight, the increasing human population with its incessant urbanisation of the landscape, and vandalism.

Interestingly, most of the above problems have been introduced to Bermuda by man who has, in various ways, has had a long history of upsetting the balance of nature.

House sparrows, first introduced in the late 1870s, are a major enemy.

Invading bluebird nesting boxes for their own requirements, the males kill any chicks found there. With the escalation of the sparrow population and the lack of natural nesting sites, the bluebird has been unable to adapt quickly enough to the changing environment.

Kiskadees, first introduced in 1956, include bluebird chicks in their diet, and starlings compete for natural nesting sites. Since bluebirds only eat live worms and grubs, it is believed that their population was seriously decimated by pesticides widely used in the 1950s and '60s, particularly on golf courses.

The tropical fowl mite, another major hazard in nesting boxes, has caused a significant number of deaths.

The popular bluebird box, first introduced by the Bermuda Audubon Society in the 1950s, has played an important part in turning the tide for the waning bluebird population. By trial and error the current model, although imperfect in keeping out sparrows and fowl mite, has proved a boon for nesting pairs and their chicks -- but not without a great deal of diligence and hard work on the part of people like the Audubon Society's Stuart Smith.

An indefatigable supporter of the bluebird conservation programme, Mr. Smith not only makes dozens of the wooden boxes for sale by the Aubudon Society and the Bermuda National Trust, but also erects and monitors boxes up and down the Island. Urging all Bermudians to get behind the nesting boxes programme, Mr.

Smith says: "It is politically correct to have a bluebird box in your yard, but the most important issue is to monitor the nesting boxes once a week during the breeding season, which runs from March to August.'' Plea to save the bluebirds "That means emptying out all old nests and cleaning the boxes either by pouring boiling water through them or washing them out with a solution of water and bleach to kill any fowl mites after the chicks fledge.'' Bluebirds nest up to three times per season, producing three to five eggs each time. It takes between 13 and 14 days for eggs to hatch, and between 15 and 20 days for chicks to fledge.

While the entrance hole precludes starlings and kiskadees from invading the boxes, sparrows, being the same size as bluebirds, can easily hop through, which is one reason why they must be checked regularly, and all traces of their existence, including nests, eggs and hatchlings, removed.

Since sparrows are extremely persistent, it may be necessary to leave the door on nesting boxes open for up to five days at a time in order to really discourage them.

"Too many people with bluebird boxes leave them unmonitored, so instead of assisting the bluebird, they simply provide breeding grounds for the enemy -- the house sparrow, which is considered a pest,'' Mr. Smith explains. "I would recommend that if they don't have time to monitor the boxes, they should take them down.'' Asked how to tell the difference between a bluebird and a sparrow's nest, Mr.

Smith says: "The bluebird's is normally a neat cup of casuarina needles and/or grasses, whereas the sparrow's is an untidy ball of grass, weeds, pieces of paper and other trash, lined with feathers.'' As for destroying sparrows' eggs, Mr. Smith says they are identifiable by their greyish hue with brown speckles, whereas the bluebird's are pale blue.

Whenever dead chicks are found in nesting boxes, they should be removed immediately before they attract ants.

While sparrows dislike monitoring, bluebirds are more accepting, and while they may show "a little agitation'' they won't abandon the nesting box as a result of human interference.

Bluebird chicks can be handled up to 12-14 days old after which, except in an emergency, they should be left alone.

While hundreds of nesting boxes have been installed across the Island, many of them around golf courses -- a favourite bluebird habitat -- fledgling statistics do not include private boxes, and therefore give only a rough idea of the programme's successes, so Mr. Smith feels steps must now be taken to secure more accurate information.

"I want to register private boxes so that we can see the state of the bluebird population other than on golf courses and public land,'' he says.

"Then we can get a better idea of how many fledglings we get per year, how bad the problem is, and whether we are winning the battle or not,'' he explains. "Such statistics may also increase environmental awareness, as well as enthusiasm for bluebird nesting boxes.'' In future, the keen conservationist would also like to visit every school on the Island to heighten awareness of bluebird conservation, and also have every 11 and 12-year-old participate in building nesting boxes.

Like all volunteers, Mr. Smith says he can only do so much, so he is urgently appealing for more people to help make bluebird boxes for sale, and also assist in monitoring some of the bluebird trails under his aegis.

For further information please contact him at 238-1868.

Photos by Andrew Dobson Home Tweet Home: (Picture at left) While the female bird keeps watch for predators, her male mate checks out special bluebird box which will be their new home during the nesting season now in progress. (Picture at right) A female Eastern bluebird waits patiently for who knows what -- a worm to surface, her chicks to fledge.