Euphagus is a small genus of New World blackbirds

Icterid

The Icterids are a group of small to medium-sized, often colorful passerine birds restricted to the New World. Most species have black as a predominant plumage color, often enlivened by yellow, orange or red. The family is extremely varied in size, shape, behavior and coloration...

. It contains two North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

n species, the Brewer's Blackbird

Brewer's Blackbird

The Brewer's Blackbird is a medium-sized New World blackbird, named after the ornithologist Thomas Mayo Brewer....

, Euphagus cyanocephalus, and the Rusty Blackbird

Rusty Blackbird

The Rusty Blackbird, Euphagus carolinus, is a medium-sized blackbird, closely related to grackles .-Appearance:...

 E. carolinus. Both species are migratory

Bird migration

Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...

, wintering in the southern United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 and Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

, although some Brewer's Blackbirds are present all year in the western USA.

A prehistoric relative, Euphagus magnirostris, is known from Late Pleistocene

Late Pleistocene

The Late Pleistocene is a stage of the Pleistocene Epoch. The beginning of the stage is defined by the base of the Eemian interglacial phase before the final glacial episode of the Pleistocene 126,000 ± 5,000 years ago. The end of the stage is defined exactly at 10,000 Carbon-14 years BP...

 fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

s found in the famous tar seeps of Rancho La Brea

Rancho La Brea

Rancho La Brea was a Mexican land grant in present day Los Angeles County, California given in 1828 to Antonio Jose Rocha and Nemisio Dominguez by José Antonio Carrillo, the Alcalde of Los Angeles. Rancho La Brea consisted of one square league of land of what is now Wilshire's Miracle Mile, ...

, California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

.

The living species are very similar medium-sized bird

Bird

Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s. Adult males have mainly black plumage

Feather

Feathers are one of the epidermal growths that form the distinctive outer covering, or plumage, on birds and some non-avian theropod dinosaurs. They are considered the most complex integumentary structures found in vertebrates, and indeed a premier example of a complex evolutionary novelty. They...

 and a bright yellow eye; the females are dark grey-brown.

They build cup nests, and the female alone incubates the eggs. They are gregarious outside the breeding season.

Both species feed on seeds and insects, the Rusty having a particularly high insect component to its diet. The fortunes of the two species are contrasting, with Brewer’s expanding east in the Great Lakes

Great Lakes

The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...

region, whilst Rusty shows a worrying decline in numbers.