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Photo: Dominic Sherony / CC BY-SA 2.0 (Wikimedia Commons)

Least Concern

Cassin’s Vireo

Vireo cassinii

Cassin's Vireo (Vireo cassinii) — Songbirds & Perching Birds of North America.

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The Cassin’s Vireo (Vireo cassinii) is a member of the Vireonidae family found in Central America & Caribbean and North America. Adults weigh 14.7 g. The IUCN Red List lists it as Least Concern.

LC Least Concern

Widespread and abundant — not currently at risk.

Where it fits

  1. Class Aves
  2. Order Passeriformes
  3. Family Vireonidae Vireos, Greenlets, Shrike-babblers
  4. Genus Vireo
  5. Species cassinii

Where it lives

Southwestern Canada through western USA to Baja California (northwestern Mexico)

Quick facts

Weight
14.7 g
Family
Vireonidae
Habitat
Woodland

How to identify

Similar birds

Biology & behaviour

Diet

The Cassin’s Vireo is a invertivore — it feeds mainly on invertebrates such as insects and other small prey.

Behaviour

A bird of semi-open forest, it spends much of its time perched in trees and shrubs.

Migration

The Cassin’s Vireo is migratory, making regular seasonal journeys between its breeding and non-breeding ranges.

The Cassin’s Vireo (Vireo cassinii) belongs to the Vireonidae family of the order Passeriformes. Its range spans Central America & Caribbean and North America. Its distribution covers NA, MA sw Canada through w USA to Baja California (nw Mexico).

It is a very small bird. Adults weighs around 14.7 g, with a wing length of about 7.4 cm and a tail of around 5.1 cm.

The IUCN Red List currently assesses it as Least Concern. That category covers species that remain widespread and reasonably abundant in the wild.

Its mapped global range covers an estimated 923,000 km².

Songs & calls

Cassin’s Vireo — Song

Recorded by Scott Olmstead Licence: CC BY-NC-SA 4.0

Frequently asked questions

How big is the Cassin’s Vireo?

The Cassin’s Vireo is a very small bird that weighs around 14.7 g.

Where does the Cassin’s Vireo live?

The Cassin’s Vireo is found across Central America & Caribbean and North America with a range covering NA, MA sw Canada through w USA to Baja California (nw Mexico), where it favours woodland, forest and well-treed country.

What family does the Cassin’s Vireo belong to?

The Cassin’s Vireo (Vireo cassinii) belongs to the Vireonidae family, in the order Passeriformes.

What does the Cassin’s Vireo eat?

The Cassin’s Vireo is a invertivore — it feeds mainly on invertebrates such as insects and other small prey.

Does the Cassin’s Vireo migrate?

The Cassin’s Vireo is migratory, making regular seasonal journeys between its breeding and non-breeding ranges.

Is the Cassin’s Vireo endangered?

The IUCN Red List currently assesses it as Least Concern That category covers species that remain widespread and reasonably abundant in the wild.

What sound does the Cassin’s Vireo make?

1 real field recording of the Cassin’s Vireo — including its song — can be played in the Songs & calls section on this page, credited to the recordist who captured it.

How large is the Cassin’s Vireo's range?

The Cassin’s Vireo has a mapped global range of about 923,000 km².

Conservation

Least Concern

Every bird benefits from bird-safe windows, native plants, and keeping cats indoors. Small changes at home add up to real protection.

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