The White-eyed Vireo is a very rare spring and fall visitor to New Brunswick. Our first record was an immature bird banded at Kent Island in September, 1980. It has been seen nearly every year since then with most sightings being near the coast lines, the Grand Manan archipelago, St. Andrews, Saint John, Miscou, etc. The adult bird shown above was seen in the Lorneville area in October, 2022.
Vireos are members of the Vireonidae family. There are 15 members of this family all in the genus, Vireo. Here in NB we normally have 5 species; Yellow-throated, Blue-headed, Red-eyed, Warbling and Philadelphia Vireos. Vireos grace our spring, summer and fall landscape with their song and plumage. They are important members of our ecosystems.
The White-eyed Vireo (Vireo griseus) is a small active grayish-yellow bird that can often be mistaken for a warbler or a kinglet. But close examination or the song can quickly identify this species. It is 13 cm long and likes to stay hidden in thick bushes. It often announces its presence by its explosive song. That is the way I found my first White-eyed Vireo. I was in South Carolina where it sometimes winters and there was this loud very unusual sound (noise?) coming from a thick small bush. I tried unsuccessfully 2 or 3 times to see what it was and could not see that bird (at least I thought it was a bird!). I started to give up but then stubbornly went back to find out what it was. With more searching and crawling around on my knees the bird finally popped out and much to my surprise I was looking at a White-eyed Vireo. I was delighted to find a new bird and to have it behave exactly as the literature describes it; secretive, explosive loud song, white eye.
The breeding range of the White-eyed Vireo is the south-eastern US extending to the area south of the Great Lakes and eastward to Pennsylvania and Massachusetts. It winters in the southern-most part of its range and in Mexico, and the Caribbean. Vagrants are found to the west and to the Maritime Provinces.
The White-eyed Vireo often announces its presence with explosive song. This hasn't been the case of the ones I have seen in the alder bushes near Lorneville probably because it was beyond the breeding season. They popped out to see who was present but were quiet. This species has a bold facial pattern with yellow spectacles and a white iris. Examining photos of this species, the iris can be white, light gray or slightly yellowish. The plumage is grayish-olive above, shows a gray back and two white wing bars. The bird is white below with grayish on the throat and yellowish on the sides. The bill is dark in colour and noticeably bigger and thicker than a warbler's bill. The young of this species looks similar to the adult but has a brown or gray iris into the late fall.
The voice of this species is distinctive. The bird is often heard before it is seen. The song is loud, explosive and is described as wren-like. I wound describe it as very varied and full of squeaks, 'chicks', and many other weird sounds. The actual mating song begins and ends with 'chick'. In fact, in Bermuda where it is common, the bird is known as the 'chick of the village' which is the people's interpretation of its song. One thing is for sure, this species does not sound like any of our native species.
The White-eyed Vireo builds its nest in thick tangled vegetation usually low to the ground. It is usually built in the fork of a sapling and is anchored with strands taken from spider webs. Both adults build the nest which is made of twigs, rootlets, strips of bark, grass, leaves, plant down, lichens, moss and bits of wasp nests. They clearly are good engineers, using all materials at their disposal. The nest is cup-shaped and is lined with fine grass and plant fibres. The male serenades the sitting female incessantly from early spring to fall, just like our native vireos. Four white eggs speckled with brown or black are laid and incubated by both adults for 13 to 15 days. The young fledge in 9 to 11 days. This species raises one brood in the northern part of its range and two in the southern part.
This species is an insectivore with a varied diet. It eats insects of many kinds and berries including caterpillars, moths, butterflies, beetles, ants, wasps, bees, grasshoppers, spiders, snails and sometimes small lizards. It eats almost entirely insects in the breeding season. During migration and in the winter it will eat berries and small fruits.
There have been slight declines in the White-eyed Vireo population since the 1960s. Habitat loss has undoubtedly played a part. The species is also susceptible to cowbird parasitism. An interesting fact about the White-eyed Vireo is that it is one of only two perching birds in the US with white eyes. The other is the Wrentit which is found in the western US.
The White-eyed Vireo is also famous in archeology. An approximately 400,000-year-old wing bone from a White-eyed Vireo is the only fossil record of any Vireo in North America. So, the White-eyed Vireo has been around for a long time!
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