A gorget is a patch of colored feather

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...

s found on the throat or upper breast of some species of 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. It is a feature found on many male hummingbird

Hummingbird

Hummingbirds are birds that comprise the family Trochilidae. They are among the smallest of birds, most species measuring in the 7.5–13 cm range. Indeed, the smallest extant bird species is a hummingbird, the 5-cm Bee Hummingbird. They can hover in mid-air by rapidly flapping their wings...

s, particularly those found in North America; these gorgets are typically iridescent. Other species, such as the Purple-throated Fruitcrow

Purple-throated Fruitcrow

The Purple-throated Fruitcrow is a species of bird in the Cotingidae family, the cotingas. It is the only species of the genus Querula....

 and Chukar Partridge, also show the feature. The term is derived from the gorget

Gorget

A gorget originally was a steel or leather collar designed to protect the throat. It was a feature of older types of armour and intended to protect against swords and other non-projectile weapons...

 used in military armor to protect the throat.

Feather wear and exposure to the sun can produce changes in the apparent color of iridescent gorget feathers. For example, fresh gorget feathers on the Anna's Hummingbird

Anna's Hummingbird

Anna's Hummingbird is a medium-sized hummingbird native to the west coast of North America. This bird was named after Anna Masséna, Duchess of Rivoli.-Description:...

are rose red; these fade to a coppery bronzy color with age.

Functions

A number of social functions have been suggested for the gorget. It may aid in mate attraction or in resource defense. It may signal social status or allow species to identify conspecifics. Among hummingbirds, gorgets are typically found only on males. In the rare instances where they are found on females, they appear to serve primarily for signaling threats.

Young hummingbirds, which need to intrude on adult territories to feed once they have fledged, all lack gorgets. This may help to make them less visible or less threatening to adult birds.