Red-Eyed Vireo declining are concern because they so effective at controlling insect pests.

The red-eyed vireo is a Neotropical migrant, breeding in deciduous and mixed deciduous forests in North America and migrating to South America to spend the winter months. Like most songbirds, red-eyed vireos migrate almost entirely at night. They are more abundant deep in the forest, but are also found in urban areas and parks with large trees.

Red-eyed vireos have been one of the most abundant and widespread birds of North America, although their population has recently declined. Forest fragmentation and destruction of both its northern breeding habitats and tropical wintering habitats has a great impact on the red-eyed vireo population. These songbirds are also vulnerable to predation by cowbirds that lay their eggs inside the nests of other bird species. Their declining populations are of particular concern because they so effective at controlling insect pests.