the red-winged blackbird (agelaius phoeniceus) is a passerine bird of the family icteridae found in most of north and much of central america .
it breeds from alaska and newfoundland south to florida , the gulf of mexico , mexico , and guatemala , with isolated populations in western el salvador , northwestern honduras , and northwestern costa rica .
it may winter as far north as pennsylvania and british columbia , but northern populations are generally migratory , moving south to mexico and the southern united states .
claims have been made that it is the most abundant and most well studied bird in north america .
the red-winged blackbird is sexually dimorphic; the male is all black with a red shoulder and yellow wing bar , while the female is a nondescript dark brown .
seeds and insects make up the bulk of the red-winged blackbird's diet .
the red-winged blackbird is one of 11 species in the genus agelaius and is included in the family icteridae , which is made up of passerine birds found in north and south america .
the red-winged blackbird was originally described as oriolus phoeniceus by linnaeus in his 18th century work , systema naturae .
but was later moved with the other american blackbirds to the genus agelaius (vieillot , 1816. the genus name is latin derived from the ancient greek , agelaios , meaning "belonging to a flock" .
the species name , phoeniceus , is from the latin word meaning "deep red" .
there are a number of subspecies , some of doubtful status , which are mostly quite similar in appearance , but the 'bicolored blackbird' a .
p .
gubernator of california and central mexico is distinctive .
the male lacks the yellow wing patch of the nominate race , and the female is much darker than the female nominate .
the taxonomy of this form is little understood , with the relationships between the two isolated bicolored populations , and between these and red-winged still unclear .
despite the similar names , the red-winged blackbird is not related to the european redwing or the old world common blackbird , which are thrushes (turdidae) .
the common name for the red-winged blackbird is taken from the mainly black adult male's distinctive red shoulder patches , or "epaulets", which are visible when the bird is flying or displaying .
at rest , the male also shows a pale yellow wingbar .
the female is blackish-brown and paler below .
the female is smaller than the male , at 1718 cm (7 in) length and 36 g (1.2 oz) weight , against his 2224 cm (9.5 in) and 64 g (2.2 oz) .
young birds resemble the female , but are paler below and have buff feather fringes .
both sexes have a sharply pointed bill .
the tail is of medium length and is rounded .
the eyes , bill , and feet are all black .
the male is unmistakable except in the far west of the us , where the tricolored blackbird occurs .
males of that species have a darker red epaulet edged with  white , not yellow .
females of tricolored , bicolored , red-shouldered and red-winged blackbirds can be difficult to identify in areas where more than one form occurs .
in flight , when the field marks are not easily seen , red-winged can be distinguished from less closely related icterids such as common grackle and brown-headed cowbird by its different silhouette and undulating flight .
