Cassin's vireo (''Vireo cassinii'') is a small North American

songbird A songbird is a bird belonging to the suborder Passeri of the perching birds (Passeriformes). Another name that is sometimes seen as the scientific or vernacular name is Oscines, from Latin ''oscen'', "songbird". The Passeriformes contains 5000 ...

, ranging from southern

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

through the western coastal states of the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

. This bird migrates, spending the winter from southern

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

(the

Sonoran Desert The Sonoran Desert ( es, Desierto de Sonora) is a desert in North America and ecoregion that covers the northwestern Mexican states of Sonora, Baja California, and Baja California Sur, as well as part of the southwestern United States (in Ariz ...

) to southern

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. The vireo is 11–14 cm (4–6 inches) in length, with a gray head, back, and flanks, and whitish underparts. It has solid white "spectacles" and white wing bars. The song, given persistently, consists of short, rough whistled phrases of several notes, spaced about 2 seconds apart. The phrases often alternate ending on a high note and a low note, giving an impression of question and answer. It prefers open woodlands of the western mountains and foothills. It is usually found in the middle to lower portions of the forest canopy, where it slowly and deliberately forages for

insects Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of j ...

among the foliage. Cassin's vireo builds a cup nest out of bark strips and down in the fork of a twig. It lays 2 to 5 white eggs with some brown spots. This species was formerly considered to belong to the same species as the plumbeous vireo and blue-headed vireo. At that time, this complex of species was referred to as the " solitary vireo". This vireo is named after the ornithologist

John Cassin John Cassin (September 6, 1813 – January 10, 1869) was an American ornithologist from Pennsylvania. He worked as curator and Vice President at the Philadelphia Academy of Natural Sciences and focused on the systemic classification of the Acad ...

References

External links

Cassin's Vireo species account
Cornell Lab of Ornithology

at USGS
Article & RangeMaps
InfoNatura NatureServe

VIREO * ttp://ibc.hbw.com/ibc/phtml/especie.phtml?idEspecie=8750 Cassin's Vireo videoson the Internet Bird Collection {{Taxonbar, from=Q1588260 Vireo (genus) Native birds of the West Coast of the United States Birds of the Sierra Nevada (United States) Fauna of the Sonoran Desert Fauna of the Lower Colorado River Valley Birds of Mexico Birds described in 1858 Taxa named by John Xantus