EMINENT ornithologist David B. Wingate has spent a lifetime studying Bermuda's birds. In the fourth article on Bermuda's birds, as part of this year's Caribbean Endemic Bird Festival, organised by the Society for the Conservation and Study of Caribbean Birds, David presents an account of our unique White-eyed Vireo.

AT the time I grew up in the late 1940s, just before the cedar scale epidemic that decimated the Bermuda cedar forest, the 'Chick-of-the-village" (so called in imitation of its cheery song) was abundant and well known to everyone. Of all the landbirds known from our fossil or early colonial period, this is the only surviving species that we can be absolutely sure existed on Bermuda before human settlement. We know this because it has the distinction of being a recognizably different (endemic) form. Its nearest relative is the White-eyed vireo, Vireo griseus<$>, of North America, but it differs in three ways that are commonly characteristic of island endemics: it has shorter wings because it is not migratory like its continental counterpart; it has a drabber, more washed out looking plumage; and its song is noticeably different - a Bermudian dialect if you will.

These differences are great enough that experienced birders can distinguish the locals from the migratory race that visits regularly in the fall and sometimes over-winters.

While the American race is sleek with bold yellow spectacles on the face, yellow flanks and bluish grey legs, our chunky-headed Bermuda birds have less yellow around the eyes and a greyer green body almost lacking yellow on the flanks. Also, their legs are blackish. But both races share the common character of two bold white bars on the wings.

It appears that the ancestors of the white-eyed vireo tribe had a propensity for colonizing islands because nearly every island in the Caribbean now has its own distinct species.

All are foliage gleaners that feed mainly on insects in the canopy of trees, but they are also highly adaptable and omnivorous, being just as happy to eat the berries of cedars, yellowwoods and sage bushes - and even the fiery hot Bermuda bird peppers - or to kill and eat lizards almost as long as themselves if occasion requires: and occasion does quite often require this when these islands are periodically raked by gales or hurricanes which decimate the insect supply. This quintessential adaptability seems to be the key to their success on these hurricane prone islands.

Considering their diminutive size at a mere 4.5 inches, they are tough little survivors, so far overcoming all of the trials and tribulations that fate has thrown at them since human settlement: and there have been many.

They survived the introduction of mammal predators like cats and rats because they are exclusively arborial and nest on the outermost branches, but the event that came closest to wiping them out was the rapid loss of Bermuda's once dominant cedar forest due to the scale epidemic in the 1950s and '60s. During that period when Bermuda was nearly denuded of trees for over a decade its population dipped alarmingly, and was not helped by the introduction of the Kiskadee in 1957, an aggressive predator on the eggs and chicks of other songbirds as well as the lizards it was brought in to control.

Fortunately, the vireo's nest is very inconspicuous and well camouflaged. It is a tiny deep cup suspended between the fork of a slender twig. It is made of bark and grass and decorated on the outside with mosses and lichens. Years ago it was discovered that they use the sticky web of the golden silk spider, Nephila clavipes, to glue the hanging nest to the twig. It requires skilful co-ordination of beak and foot to gather and transport this dangerous material which is easily capable of ensnaring an unwary small bird that flies into it.

Generally they prefer to use the sticky silk from the spider's yellow egg cases. Like most island birds our vireo lays smaller clutches of 2 - 3 eggs instead of the continental 4 - 5. The eggs are white with tiny black dots. Nesting usually begins in May and incubating adults sit low in the nest and are virtually undetectable, but if you can find a nest you can watch from a foot away without flushing them!

Chick-de-willy pairs stay together, forage together and sing their cheery song all year round. Many earlier Bermuda ornithologists have remarked on their confiding, almost cheeky nature, often stopping to scold at you from a few feet away. I once managed to reach out and stroke the breast of a juvenile which was accompanied by its parents on Nonsuch Island.

Sadly, few people on Bermuda today seem to be aware of its continued existence.

One of the most frequently asked questions I get from old timers who remember it from their childhood is "What ever happened to those Chick de willies that we used to see as children?"

Most are surprised when I tell them that they are still doing quite well on those dwindling areas of Bermuda that have not yet been totally urbanised.

Fortuitously, they are equally happy in those dense thickets of invasive tree species like the Fiddlewood, Brazil pepper and Casuarina that have grown in to replace the original cedar and sagebush forest. Indeed, the invasive woodlands are typically much denser and taller statured than the cedar forest ever was - sometimes up to three times as high.

So what the vireo has lost in a real extent of woodland due to urbanisation has partly been compensated for by increased tree height and foliage density.

There, in our woodland reserves, parks and nature reserves, it continues to sing its cheery song and would no doubt still be attracting our attention were it not for the constant din of modern motor traffic and the heavy excavating machinery that continues to eat away at its last oases.