Bird Photos
Species Accounts
Conservation Issues
| |
Red-eyed Vireo
(Vireo olivaceus)
Banded September 13, 1997 - Carmel, Indiana
General Information
|
The Red-eyed Vireo is a Neotropical migrant
that makes its way from its home in Central and South America to the deciduous woodlands
of North America to select a territory, win a mate and raise its young. Its persistent
song of short individual phrases, as many as 40 to 60 per minute, is commonly heard in
forests throughout the summer breeding season.
|
Figure 1 - Male Red-eyed Vireo
|
Figure 2 - Male Red-eyed Vireo
|
The black border on the white eyebrow stripe
and the gray distinguishes this species from other species of vireos that occur in North
America (except in South Texas, where the similar Yellow -green Vireo (V. flavoviridis)
occurs). The sexes are similar. Immature birds have a brownish iris that changes to red by
the following spring.
|
These birds are important to maintaining the
health of our forests. They consume large quantities of insects and caterpillars harmful
to tree foliage. It is an effective predator on gypsy moths, fall webworms, tree hoppers,
scale insects and others. On their wintering grounds, however, they switch to fruits.
|
Figure 3 - Male Red-eyed Vireo
|
Figure 4 - Red-eyed Vireo
|
The female builds a cup nest of bark, grass,
spider webs and other plant materials suspended in the fork of a horizontal branch. Three
to 5 eggs are produced. Both the male and the female feed the young, who leave the nest
after about 12 days. |
A view of the upper wing coverts of an
immature male. In the fall, contrast of old and new flight feathers is an aid to
separating hatching year birds from adult birds. |
Figure 5 - Upper Wing Coverts
|
Figure 6 - Primary Flight Feathers
|
Vireos as a group have 10 primary flight
feathers (here numbered left to right). The 10th primary of the Red-eyed Vireo is a full
sized feather (shown here as the feather to the right). The 10th primary of most other
vireo species is much reduced. This characteristic, along with plumage, wing length and
culmen length, is useful to identify this species in the hand.
|
Red-eyed Vireos were once considered one of
the three most abundant bird of the forests of Eastern North America. Their persistent
song is legendary among songbirds. A single individual was once heard to sing 22,197 songs
during a single day (de Kiriline, L. 1954). |
Figure 7 - Underwing Coverts
|
Figure 8 - Rectrices (Tail Feathers)
|
Populations of Red-eyed Vireos are declining.
Unfortunately, the Vireo nest is one of primary targets of Cowbird parasitism. Female
Cowbirds find and lay their eggs in the vireo nest. The Cowbird eggs hatch early and the
young Cowbirds out compete the young vireos for food and space with the result that the
young vireos perish.
|
Because these birds are effective at
controlling insect pests, their declining populations are a matter of concern. |
Figure 9 - Undertail Coverts
|
Nesting Behavior
The female builds a cup nest of bark, grass, spider webs and other plant materials
suspended in the fork of a horizontal branch. Three to 5 eggs are produced. Both the male
and the female feed the young, who leave the nest after about 12 days.
Banding Recoveries
Because these birds are effective at controlling insect pests, their declining
populations are a matter of concern. According to data at the Bird Banding Laboratory in
Laurel. MD, 174,175 Red-eyed Vireos have been banded since 1955. Of these, 189 have been
recovered, a recovery rate of 0.11%.
Conservation Status
Red-eyed Vireos were once considered one of the three most abundant birds of the
forests of Eastern North America. Their persistent song is legendary. A single individual
was once heard to sing 22,197 songs during a single day (Lawrence 1953).
Literature Cited:
Lawrence, L. de K. 1953. Nesting life and behavior of the Red-eyed Vireo. Canadian
Field-Nat. 67:47-77.
Back to Top | Back to Bird
Photos Menu
All images are courtesy of CWBO. All image copyrights are owned by CWBO.
Any use of these images must have permission of CWBO. |
|
