Vireonidae

Vireonidae is a family of small to medium passerine birds commonly referred to as vireos. They are found primarily in the New World, with the greatest diversity in tropical Central and South America. North American vireos breed across temperate North America and migrate to the tropics for winter, while many tropical species stay year‑round.

Vireos are typically slender, with dull green, gray, or olive plumage. They usually have a fairly straight, pointed bill and a soft, often musical voice. They are insectivorous, but fruit is taken opportunistically, especially outside the breeding season.

They glean insects from foliage, often moving cautiously through the canopy. Some species will hover briefly to catch prey or sally after flying insects. Pair bonds are common, and many vireos are territorial during the breeding season.

Nests are cup-shaped and placed in trees or shrubs, sometimes in awkward-for-sight locations. Eggs are often pale with brown or gray markings. Both parents typically participate in incubation and feeding of the young, with fledging periods varying by species and region.

Taxonomy within Vireonidae includes several genera, notably Vireo (the true vireos) and Hylophilus (greenlets), among others. The family comprises around 50 species in total. Molecular studies have clarified relationships within the group, prompting reclassification and a better understanding of evolutionary history.

Conservation status varies by species. Many vireos are common or locally abundant, but habitat loss, especially in tropical regions and on islands, threatens several species with restricted ranges. Ongoing monitoring and habitat protection are important for sustaining populations.