New World Blackbirds and Orioles (Icteridae)

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New World blackbirds and orioles

(Icteridae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Icteridae

Thumbnail description
Medium to large-sized songbirds with short and massive to rather long and slender conical bills; many are colorful and sexually dimorphic in both size and coloration

Size
6.7–21.5 in (17–55 cm); 0.6 oz–1.2 lb (16–528g)

Number of genera, species
25 genera; 103 species

Habitat
Forest, woodlands, marshes, and grassland

Conservation status
Critically Endangered: 3 species; Endangered: 4 species; Vulnerable: 4 species; Near Threatened: 1 species; Extinct: 1 species

Distribution
North, Central, and South America (Alaska to Cape Horn)

Evolution and systematics

The New World blackbirds, troupials, and meadowlarks (Icteridae) include the beautiful orioles (Icterus) and caciques (Cacicus), as well as many other colorful songbirds. The icterids are variously treated as a family, subfamily, or tribe in a more inclusive family (Emberizidae or Fringillidae) that also contains a number of other songbirds having only nine primary wing feathers. Most sources separate these at the familial level. Other groups of birds that are closely related to the blackbirds are the olive warbler (Peucedramus taeniatus), bananaquit (Coereba flaveola), and other New World warblers (Parulidae), and the tanagers, buntings, and other New World finches (Emberizidae). These birds no doubt evolved in the New World, and today all, with the exception of the Emberizidae, are confined in their distribution to the New World. The Icteridae almost certainly evolved in South America where today the largest number of species occur. One large genus of blackbirds, the orioles, may be of Central American origin. These families probably differentiated rather recently in geological time, perhaps during the Pliocene. All of the fossils of icterids, however, are from the Pleistocene or Holocene.

Molecular studies delineate five distinct lineages within the Icteridae. These are: (1) the grackles and allies (including Agelaius, Euphagus, Quiscalus, Molothrus, and 11 other genera), (2) the caciques and oropendolas (Cacicus and Psarocolius), (3) the orioles (Icterus), (4) the meadowlarks and allies (Dolichonyx, Xanthocephalus, Sturnella, and Leistes), and (5) the cup-nesting caciques (Amblycercus holosericeus).

Physical characteristics

Icterids are remarkably diverse in size. They range from the slim orchard oriole (Icterus spurius), which weighs as little as 0.6 oz (16 g), to the robust Montezuma's oropendola (Psarocolius montezuma), which can weigh as much as 1.2 lb (528 g), making it one of the largest songbirds. Most species are brightly colored, commonly with black (often with a bright metallic gloss) and yellow, but many species have prominent red coloration, and some of the oropendolas are greenish. Some species have a neck ruff; others, a sparse crest.

The family name comes from the Greek ikteros which was a yellow bird, perhaps the golden oriole (Oriolus) which was

thought to cure jaundice. The English vernacular name for the New World orioles (Icterus) was given to them by early naturalists who thought them to be related to the Oriolus orioles of the Old World, but today it is realized that these birds are not closely related.

There is a great deal of variation in bill size and shape in the Icteridae. Many blackbirds have rather long, stout, and pointed bills; the ridge of the upper mandible is often straight in profile, and may extend onto the forehead, forming a frontal shield. Some of the orioles have slim, gracile bills that are slightly downturned, and the bobolink (Dolichonyx oryzivorus) and some of the cowbirds (Molothrus) have a finch-like conical bill. Blackbirds—particularly those species that forage extensively on the ground—have rather large legs and long claws.

Many species of blackbirds are strikingly sexually dimorphic in size. This is especially true in species where males are commonly polygynous (a male will be mated to two or more females in a single breeding season), e.g., Psarocolius, Agelaius, Quiscalus, and Xanthocephalus. As well, many blackbirds are sexually dimorphic in color. In dimorphic species, the males tend to have a bright display plumage whereas females are dull and relatively inconspicuous; the young tend to resemble females, and males may not develop their full display plumage until they are two years of age. Plumage dimorphism is characteristic of icterids that breed in north temperate areas. Within the orioles, the species that breed in North America, including some of the Mexican species, are dimorphic in color, whereas the tropical species (including the three South American species) are monomorphic (although the female is sometimes somewhat less brightly colored).

Distribution

New World blackbirds are widespread in the New World, and, with the exception of a few records of vagrant individuals, they are confined to the New World. The species with the northern-most range, the rusty blackbird (Euphagus carolinus), breeds from the limit of trees in northern Alaska, northern Yukon, southwestern Nunavut, and Labrador southward into central Alberta and into northern-most parts of the northeastern United States. The species with the southernmost range, the austral blackbird (Curaeus curaeus), is found south to Cape Horn, and the long-tailed meadowlark (Sturnella loyca) breeds from Chile and Argentina south to the Beagle Channel Islands in Tierra del Fuego and in the Falkland Islands. Between these extremes, there is no place in the Americas where there is not at least one breeding icterid. The areas of the greatest richness of species are southern Mexico, northwestern South America, and southern Brazil, Paraguay, Uruguay, and northeastern Argentina. The genus with the largest number of species, Icterus, reaches its greatest richness in Central America where nine species breed, and an additional three species winter. The oropendolas (Psarocolius), which are forest dwelling, are confined to the Neotropics; two species are found north to the humid forests of southern Mexico. Nine of the 10 species of caciques likewise are limited to the Neotropics, although one species does range north to the Pacific coastal lowlands of central Sinaloa. The genus Euphagus, with two species, is the only genus restricted in range to North America (one winters south to central Mexico). The grackles (Quiscalus), which are closely related to the Euphagus blackbirds, are also found in North America, but some species are also found in Central and northern South America and in the Caribbean. Several studies have indicated that the blackbirds that are presently placed in the genus Agelaius should be divided into two genera, one found in North and Central America and the Caribbean, and the other confined to South America.

Habitat

New World blackbirds are found in a variety of different habitats, such as forests, savanna, grasslands, deserts, marshes, and bogs. The caciques and oropendolas are all found in forests, commonly humid lowland tropical forests. Many species, however, are associated with forest edge or clearings and are not generally found in the forest interior, and some are found in montane cloud forests. The yellow-winged cacique (Cacicus melanicterus), which occurs north to at least central Sinaloa, Mexico, may be found in thorn scrub, plantations (coconuts, mangos) and other settled areas, and in mangroves.

Most of the orioles (Icterus), the melodious, Brewer's, and yellow-shouldered blackbirds (Dives dives, Euphagus cyanocephalus, and Agelaius xanthomus), and the common and greater Antillean grackles (Quiscalus quiscula and Q. niger) are found in open woods, early successional habitats, riparian woods, savannas, or urban areas. The bobolink, meadowlarks (Sturnella), and the brown-headed cowbird (Molothrus ater) are found in grasslands, the yellow oriole (I. nigrogularis) and Bolivian blackbird (Oreopsar bolivianus) are found deserts, and the rusty blackbird occurs in boreal bogs. Lastly, a large number of blackbirds nest in marshes. Included in this group are the widespread and familiar North American red-winged blackbird (Agelaius phoeniceus) and other species in this genus, the yellow-headed blackbird (Xanthocephalus xanthocephalus), the marshbirds (Pseudoleistes), and the scarlet-headed blackbird (Amblyramphus holosericeus) of South America, and several of the grackles. Many of these marsh-nesting blackbirds are colonial or breed in grouped territories.

Behavior

Although they may occasionally sing during the night, blackbirds are diurnal. During migration and winter, many species form flocks—sometimes huge flocks—when they are both foraging and roosting. In the mid-1970s, there were 723 major roosting flocks in the United States containing an estimated 438 million blackbirds. An estimated 200 million icterids winter in Arkansas, Louisiana, Tennessee, and Mississippi. In the west, particularly in rice growing areas of east Texas and California, another 139 million icterids winter, and in North Carolina about 76 million winter. There are advantages to the birds in these large roosting flocks. There is strength in numbers: there are more birds to sight potential predators, and it can be dangerous for flying predators to enter a large flock of birds. There is also protection from rain, wind, and heat loss in a large flock. A disadvantage is that there is not sufficient food close to a large roost to feed the large numbers of birds present, and some individuals must travel up to 60 mi (100 km) each direction every day to reach feeding areas where the food has not already been depleted. Migrating and wintering blackbirds often forage in flocks as well, but foraging flocks are generally smaller than roosting ones. New World blackbirds walk rather than hop on the ground.

Blackbirds perform a wide variety of displays, many of which are quite interesting to watch. One common and widespread icterid display is the "song-spread" (or "rough-out") display. In this display, the bird (most commonly a male, but females of some species also do this) spreads its wings somewhat, and raises the feathers on its shoulders, back, and neck; on the red-winged blackbird this displays the bright red epaulets prominently. Some birds, such as some of the cowbirds (Molothrus), have a neck ruff that is exaggerated during this display. The "song-spread" display is accompanied by song. The "song-spread" appears to function both in territorial defense and for mate attraction. The "bill-tilt" display is another display that many blackbirds use. In this display, the feathers are sleeked, and the bill, head, and body are pointed upward. "Bill-tilting" is aggressive, and is used during encounters both within and between sexes. Many blackbirds have "flight-song" displays, and in some species these displays can be spectacular. Male white-browed blackbirds (Sturnella superciliaris) fly to a height of about 60 ft (20 m) and parachute

to the ground while giving their song. The "flight-song" of the bobolink is also spectacular. The male, with a fluttery flight and wings bowed—not rising above the horizontal, and tail pointed downward, fly up to perhaps 30 ft (10 m) from the ground while uttering their bubbling song. Male redwinged blackbirds commonly give a rapid series of notes, "tseee tch-tch-tch-tch chee-chee-chee" while in flight. Female blackbirds characteristically arch their backs, and with their heads down raise their tails and shiver their wings in a pre-copulatory display. Injury feigning distractions are given by some blackbirds, but are not common in the family. Male oropendolas perform a "bow-display." In this display, the male sits on a branch, partially opens his wings, thrusts his head downward and tail upward, until he is completely upside down, with his tail at right a right angle to his body, then rights himself as he finishes his song, and shakes his wings.

Feeding ecology and diet

The largely arboreal oropendolas, caciques, and orioles commonly forage by gleaning food from vegetation in trees. These birds, like many other blackbirds, often feed by

gaping—inserting their closed bills into a flower, fruit, or stem, then opening the bill to expose food or facilitate nectar feeding. Twigs and branches often harbor small insects, especially ants. By gaping into these branches, birds capture these insects. Bark can be pried loose by gaping, and yellow-backed orioles (Icterus chrysater) gape under the scales of pine cones, as well as flake away bark, in the search for insects. Black caciques, such as the Ecuadorian cacique (Cacicus sclateri), split the slender stems of bamboo to find insects, but like most blackbirds are generalists when foraging, eating fruit and nectar in addition to insects. An oriole often gapes when eating fruit: it thrusts its closed beak into the fruit, then opens it and uses its tongue to drink the laked juice. They also forage for nectar (or sugar in hummingbird or oriole feeders) and many commonly forage on the ground.

The species of blackbirds that live in grasslands feed mostly on the ground, and the marsh-dwelling species also commonly feed on the ground, especially in the winter. Meadowlarks commonly feed by gaping. They insert their long bills into the ground, then open the mandibles to expose insect prey or grain; the muscles used for opening the bill are particularly well-developed in these birds. Particularly during the winter, many blackbirds forage extensively on the ground for grain and other seeds, and some species eat small vertebrate animals. Red-winged blackbirds have been observed to eat Nelson's sharp-tailed sparrows (Ammodramus nelsoni), and rusty blackbirds and grackles have been observed eating birds as large as white-throated sparrows (Zonotrichia albicollis). Grackles are also adept at catching small fish in shallow waters, and they can crush acorns with their powerful bills. Black-backed orioles (I. abeillei) are one of the few birds that will eat the often toxic monarch butterflies (Danaus plexippus). The toxicity of these butterflies is derived from some of the plants that they eat, and the majority of the butterflies are only weakly toxic. The orioles taste each butterfly that they capture, and release the more toxic ones. Blackbirds are not adept at flycatching, but they do take some low-flying insects. In winter, many species of blackbirds forage in flocks on the ground. Commonly these flocks are composed of mixed species. In North America, flocks often contain a combination of cowbirds, grackles, red-winged blackbirds and, in the west, yellow-headed blackbirds and Brewer's blackbirds. When the birds are foraging, these flocks appear to roll along as the birds toward the back of the flock fly to the front of the flock as it moves along.

Reproductive biology

Most icterids build an open cup-shaped nest, woven into supporting vegetation or in a crotch in a shrub. Hole nesting is extremely rare in blackbirds, but occasionally nests are placed cavities. The only species that regularly nests in holes is the Bolivian blackbird, which nests in arid areas on the eastern slope of the Andes, where there are few trees or shrubs. Thus, it is not surprising that they place their nests in crevices in cliffs. Baywings (formerly called the bay-winged cowbird) (Agelaioides badius) usually lay their eggs in nests built by other species of birds, and they seem to prefer the domed nests of ovenbirds (Furnariidae); they also will nest in nest boxes. Orioles, caciques, and oropendolas weave distinctive pendant bag nests, which are suspended from the branches of trees, although in Louisiana, where they often nest in marshes; orchard orioles (Icterus spurius) often weave their nests into supporting reeds. Nests of oropendolas may be over 50 in (125 cm) long. The nests of grassland icterids usually are placed on the ground, often a nest woven of fine grass, and placed at the base of a tuft of grass that may overhang the nest. The nests of some of the meadowlarks are domed, and there may be runways in the grass leading to the nest. The cowbirds (Molothrus) are brood parasites, that is, they lay their eggs in the nests of other species of bird. Some of these, such as the brown-headed and shiny cowbirds (M. ater and M. bonariensis) parasitize a large number of host species, but the screaming cowbirds (M. rufoaxillaris) lay their eggs only in the nests of baywings, and a few other species of blackbirds. Many species of blackbirds are colonial, or at least have grouped territories. Nest building is done exclusively or principally by the female. The number of eggs and their shape and coloration varies among species. Some oropendolas may lay only a single egg, whereas the parasitic brown-headed cowbird may lay a great many eggs in any season (perhaps 30; one captive female laid 77), but these tend to be laid daily, in sequences of one to seven eggs. They vary in shape from rather round to elongated; they are glossy and tend to be marked with spots and blotches, although some cowbirds may lay unmarked eggs.

Most blackbirds are at least socially monogamous, but a great many species are polygynous. Polygyny seems to be particularly frequent in colonial marsh-nesting blackbirds and many of the colonial caciques and oropendolas. In the polygynous

crested oropendola (Psarocolius decumanus), females greatly outnumber males, perhaps by as much as 10 to one in some populations. The much-studied red-winged blackbird commonly is polygynous, but some individuals are monogamous; in this species—and probably many others—extra-pair copulations are common. Females appear to solicit such copulations. A male red-winged blackbird may have as many as 15 mates. Not surprisingly, males give more assistance to females in monogamous pairs than in polygynous ones. The marsh-nesting scarlet-headed blackbird of South America, and some other marsh-nesting species, however, are monogamous.

Conservation status

Many species in the Icteridae are among the most numerous and successful of American songbirds. They are a conspicuous component of the fauna of many grasslands and marshes, and some, such as many of the grackles and cowbirds, have adjusted well to human-induced changes to the environment. Nonetheless, some 7% of the species are classified as being under some level of threat, ranging from endangered to further protection desirable.

The Martinique oriole (Icterus bonana) is Vulnerable, and Forbes's blackbird (Curaeus forbesi) is listed as Critically Endangered. The oriole is endemic on the West Indian island of Martinique where it was originally distributed throughout the forested areas of the island at lower elevations. The principal threat to this species is brood-parasitism from the shiny cowbird, which colonized the island during the late 1940s and is increasing in abundance. Today, about 75% of the nests are parasitized by cowbirds. Forbe's blackbird is known with certainty from only two regions near the Atlantic coast of Brazil. In the 1880s, when this species was first described, it was said to be local in occurrence, but apparently common where found; however, they are very similar in appearance to the chopi blackbird (Gnorimopsar chopi), so there is some uncertainty about their status because many so-called records of Forbe's blackbirds may have been of chopi blackbirds. Forbe's blackbird is threatened by deforestation and by pressure from parasitism by shiny cowbirds.

The pampas meadowlark (Sturnella defilippii) is Vulnerable, and the Baudó oropendola (Psarocolius cassini) and redbellied grackle (Hypopyrrhus pyrohypogaster) are listed as Endangered. The meadowlark was apparently always rare in Uruguay and Brazil, but was formerly common in central-eastern Argentina. Today, however, cultivation and over-grazing has resulted in a serious decline in their numbers. The red-bellied grackle is endemic to the Andes of Colombia. Although in the past these were not uncommon birds in humid

tropical forests, habitat destruction has led to declines in numbers, and today they are local in distribution, although common in a few sites. The saffron-cowled blackbird (Xanthopsar flavus) is a Vulnerable bird of moist grasslands, marshes, agricultural fields, and dry bushy areas of southern Brazil, Paraguay, eastern Argentina, and Uruguay. For reasons that are not well known, but include habitat destruction, their numbers have declined sharply in the last century, especially since the 1970s. The selva cacique (Cacicus koepckeae) is Vulnerable as well. This cacique is known only from the type-locality (the site where it was first collected), in the lowlands of Peru, although there are other sight records from Manú National Park in Peru. Little is known of their biology, but they are probably extremely rare. Although only seven of the approximately 103 species of blackbirds are listed, three of these represent monotypic genera (that is, they are the only species in that genus). In other words, if those three species were to go extinct, three of 25 genera, or approximately 12%, would be lost, leading to a fairly substantial loss of the diversity that has evolved in the Icteridae.

Significance to humans

Many North American blackbirds are considered agricultural pests in many areas where flocks of them descend to feed in grain fields (rice, corn) or feed lots, and thus compete with humans and their livestock for food. As well, they often congregate in immense flocks in migration and winter, and when these flocks gather in densely inhabited areas—as they frequently do—concern is often expressed that they could constitute a threat to human health. Additionally, many people find the noise associated with a blackbird flock to be unpleasant and the excrement unaesthetic, particularly when they are roosting in a city park. Consequently, there is often pressure on government and game officials for mass extermination, and millions have been destroyed.

New World blackbirds have also played an important part in biological research, in part because many are common, conspicuous, and easily observed, and in part because of the great diversity of lifestyles and behaviors represented in the family. Therefore, they have been important subjects of many major studies of behavior, breeding biology, mating systems, and ecology. In North America, studies of the yellow-headed and red-winged blackbirds have been important in the development and testing of theories about territoriality and mating systems of birds, and the paternity of young. These studies have helped to answer many general questions in biology.

Species accounts

List of Species

Montezuma's oropendola
Yellow-rumped cacique
Yellow-billed cacique
Baltimore oriole
Jamaican blackbird
Oriole blackbird
Yellow-headed blackbird
Yellow-hooded blackbird
Red-winged blackbird
White-browed blackbird
Long-tailed meadowlark
Western meadowlark
Brown-and-yellow marshbird
Chopi blackbird
Melodious blackbird
Great-tailed grackle
Rusty blackbird
Baywing
Brown-headed cowbird
Bobolink

Montezuma's oropendola

Psarocolius montezuma

taxonomy

Cacicus montezuma Lesson, 1830, Mexico.

other common names

French: Cassique de Montezuma; German: Montezumastirnvogel; Spanish: Chacarero de Montezuma, Oropéndola de Moctezuma.

physical characteristics

15–20 in (38–50.5 cm); female 7–9 oz (198–254 g), male 12.5 oz–1.2 lb (353–528 g). Sexes similar in color. A large chestnut oropendola with a black head, a bare blue cheek patch, a small pink patch at the base of the lower bill, orange-tipped black bill, and yellow lateral tail feathers.

distribution

Resident from southeastern Mexico south to central Panama.

habitat

Tropical lowland forests and secondary forests, to 3,300 ft (1,000 m).

behavior

During the breeding season they are highly colonial. Females forage away from the colony in small groups. Males often feed solitarily. Males have an elaborate courtship display: they bow forward, pointing their bill downward, and fan their tail, while uttering a characteristic vocalization.

feeding ecology and diet

Forage in trees; their diet is almost exclusively fruit.

reproductive biology

Highly polygamous; successful males mate with several different females. Females weave a long basket-like nest of grasses and other fibers, which is suspended from the tips of branches of a tree; nests are up to 47 in (120 cm) in length. Oropendolas are highly colonial with over 60 nests in some colonies. Nesting trees are characteristically tall trees that are away from other trees (so that it is difficult for monkeys and other arboreal predators to get to them). Generally two eggs are laid January–May. Incubation about 15 days; young fledge about 30 days.

conservation status

Not threatened. Montezuma oropendolas are locally common on the Caribbean coast of Central America, but generally local on the Pacific coast of Nicaragua, northwestern Costa Rica, and Panama.

significance to humans

None known.

Yellow-rumped cacique

Cacicus cela

taxonomy

Parus cela Linnaeus, 1758, Surinam.

other common names

French: Cassique cul-jaune; German: Gelbbürzelkassike; Spanish: Charro de Rabadilla Amarilla.

physical characteristics

8–11 in (22–29 cm); female 2.4–3.9 oz (67–110 g), male 2.9–4.3 oz (81–121 g). Sexes similar in color. A large black cacique with a yellow rump, undertail coverts, and wingbar. The bill is pale yellow.

distribution

Resident from southern Panama to northern and central South America, east of the Andes south to southern Bolivia and central and eastern Brazil, and west of the Andes in western Ecuador and northwestern Peru.

habitat

Tropical lowland forest edge and river-edge forest.

behavior

Yellow-rumped caciques often nest colonially, and at colonies females outnumber males. Males display by roughing out their feathers, especially the yellow rump feathers, and with their body in a horizontal position, they flutter their wings and thrust their head downward while vocalizing.

feeding ecology and diet

They feed in trees, primarily in the outer foliage or in the canopy. Their food is primarily insects, but they also eat fruit. They often feed in pairs or small groups, but males often feed singly.

reproductive biology

Successful males mate with several different females in a season. Within both sexes, dominance hierarchies are established, with the largest individuals at the top of the hierarchy. Dominant males obtain the most mates, and dominant females can occupy prime nesting sites, near wasp nests; they often nest on islands. The nest is a hanging basket, averaging about 17 in (43 cm), woven of palm strips, and suspended from a tree branch. Generally two eggs are laid; eggs can be laid at any season, but most nesting takes place in the driest times of the year. Incubation 13–14 days; fledging takes place after 24–30 days.

conservation status

Not threatened. Widespread and common in suitable habitat.

significance to humans

None known.

Yellow-billed cacique

Amblycercus holosericeus

taxonomy

Sturnus holosericeus Deppe, 1830, Veracruz, Mexico.

other common names

French: Cassique à bec jaune; German: Gelbschnabelkassike; Spanish: Charro Piquihueso; Cacique Piquiclaro; Pico de Plata.

physical characteristics

8.5–10 in (22–25 cm); female 2 oz (56 g), male 2.5 oz (71 g). Sexes similar in color. Entirely black, with a whitish yellow bill; eyes yellow.

distribution

Resident from coastal eastern Mexico south to northern Colombia; in South America in the mountains from northern Venezuela south to northern Bolivia.

habitat

Lowland and montane evergreen forests; secondary forests to 9,800 ft (3,000 m). In the highlands, it is characteristic of bamboo thickets.

behavior

The yellow-billed cacique is a skulking bird of dense under-growth. They typically wander in the undergrowth in pairs or family groups.

feeding ecology and diet

Forage mostly in low thickets where they poke into rolled leaves, bamboo shoots, or hammer at branches to get insects. They have been observed following army ants to pick up insect prey.

reproductive biology

Monogamous. Nests are a cup of leaves and vines, placed within 3 ft (1 m) of the ground. Generally 1–2 eggs are laid. Breeding season varies geographically; in Costa Rica nesting takes place in February–June; in South America, in November– April. Incubation and fledging times not reported.

conservation status

Not threatened. They are locally common in thickets, clearings and second growth, habitats that are created by clearing of primary forests.

significance to humans

None known.

Baltimore oriole

Icterus galbula

taxonomy

Coracias galbula Linnaeus, 1758, Virginia.

other common names

English: Northern oriole, black-backed oriole, Bullock's oriole; French: Oriole de Baltimore; German: Baltimoretrupial; Spanish: Bolsero de Baltimore.

physical characteristics

7–8 in (18–20 cm); female 1–1.4 oz (28–41 g), male 1.1–1.4 oz (31–40 g). Sexually dimorphic in color. Males with a black head, wings, and middle tail feathers, and yellow-orange on the breast, belly, shoulder, and the tips of the tail, with white markings in their wings. Males in their second year resemble females. Females, which are variable, are yellowish or orangish green, usually with some black on the head, and greenish gray wings. Juveniles resemble females, but lack black, and are usually duller in coloration.

distribution

Breeds in eastern North America, from central Alberta and southern Quebec south to northern Louisiana and central Georgia. Winters from central Mexico south to northern South America, Florida, Jamaica, and along the coast of southern California.

habitat

Woodland edge and open woodlands.

behavior

Territorial during the breeding season. Males defend a territory with songs and chasing. In winter, solitary or found in small groups.

feeding ecology and diet

Forage mostly in trees, gleaning insects, or eating fruit and insects. Also forage on ground or low in vegetation.

reproductive biology

Monogamous. Females (sometimes with some assistance from males) weave a bag-like nest of grasses, which is suspended from the branches of a tree. Generally 4–5 eggs are laid from May to mid-June. Incubation 11–14 days; fledging 11–14 days. Single brooded, but replacement clutches may be produced.

conservation status

Not threatened. Widespread and common, but numbers declining in many areas. Destruction of suitable habitat for them on the wintering grounds may be affecting numbers.

significance to humans

Can be an important predator on defoliating insects; one of the few birds that eat significant numbers of tent caterpillars (Malacosoma).

Jamaican blackbird

Nesopsar nigerrimus

taxonomy

Icterus nigerrimus Osburn, 1859, Jamaica.

other common names

French: Carouge de la Jamaïque; German: Bromelienstärling; Spanish: Pradero Jamaicano.

physical characteristics

7 in (18 cm); 1.4 oz (39 g). Sexes similar in coloration. Uniformly black.

distribution

Resident in Jamaica.

habitat

Wet montane forests.

behavior

Territorial. Jamaican blackbirds spend most of their time foraging in the forest canopy. They vocalize frequently.

feeding ecology and diet

Forage in trees, searching epiphytes for invertebrate food.

reproductive biology

Monogamous. The bulky nest is constructed of rootlets and epiphytic orchids, and is placed against the trunk of a tree in the lower canopy. Two eggs are laid in May–July. Incubation is about 14 days. Single brooded.

conservation status

Endangered. Although locally common, they are found only in places where there is mature rainforest, habitat that is being destroyed for coffee plantations.

significance to humans

None known.

Oriole blackbird

Gymnomystax mexicanus

taxonomy

Oriolus mexicanus Linnaeus, 1766, Cayenne.

other common names

French: Carouge loriot; German: Nacktaugentrupial; Spanish: Tordo Maicero.

physical characteristics

10.5–12 in (27–30 cm); 3.3 oz (93 g). Sexes similar in coloration, but males somewhat larger. Head and underparts, and epaulets (shoulders) bright yellow, and black otherwise; blackish patches of skin around the eyes and on the malar area. Young are like adults, but have a black cap.

distribution

Resident in much of Venezuela, central Colombia, and along the Amazon River from eastern Ecuador east to the Atlantic Coast. Sparse in the Guianas.

habitat

Marshy area and open areas with scattered trees and palms.

behavior

Territorial during the breeding season. Oriole blackbirds are usually observed in pairs or small flocks, but sometimes roost in large flocks. They typically sit on low perches, such as fence posts or low branches in trees, and walk on the ground. When singing, males rough out the feathers of the neck, fan their tails, and droop their wings.

feeding ecology and diet

They mostly forage on the ground, slowly walking and picking up grain, or probing in the ground. They pick fruit from trees.

reproductive biology

Monogamous. The nest is a bulky cup of grasses and other vegetation, built by the female with some help from the male, and placed 20–25 ft (6–8 m) up in a tree. Generally three eggs are laid in August–December in Guyana, and March in Peru. Incubation 18–20 days; fledging time not reported.

conservation status

Not threatened. Oriole blackbirds are common in appropriate habitat. Clearing of forests probably creates habitat that is suitable for them.

significance to humans

They frequently raid corn fields, and locally oriole blackbirds may be pests.

Yellow-headed blackbird

Xanthocephalus xanthocephalus

taxonomy

Icterus icterocephalus Bonaparte, 1826, Nance Co., Nebraska.

other common names

French: Carouges à tête jaune; German: Brillenstärling; Spanish: Tordo Cabeciamarillo, Tordo Cabecidorado.

physical characteristics

9–10 in (23–25 cm); female 1.5–2 oz (42.5–56 g), male 2.6–3 oz (72.5–85.5 g). Sexually dimorphic in color. Males black, with a bright yellow head, throat, and breast, black between the eye and bill and on the chin, and a large white patch on the primary wing coverts. Females are brown above, with a golden yellow throat and stripe above the eye, and heavy brown streaks on their breast; in worn (summer) individuals, the yellow is paler and somewhat brighter. Young birds resemble females, and males in their first summer resemble summer females.

distribution

Breeds from eastern British Columbia and the Canadian prairies, east locally to southern Ontario, and south through the American west to eastern Washington and California, south to northern New Mexico. Resident in the lower Colorado River valley, and locally in south-central California. Winters from central Arizona, New Mexico, and western Texas south to central Mexico.

habitat

Freshwater marshes, with cattails, tules, or bullrushes. In migration and winter, found in agricultural fields.

behavior

Territorial during the breeding season. Males defend a territory with songs and chasing. Males perform a "song spread display," in which the wings are held up in a V as they vocalize. Both sexes perform a display in which the wings and tail are partially spread, the head turned, and the bill pointed upward. In winter, found in flocks, often enormous ones that contain several different species of blackbirds as well as European starlings (Sturnus vulgaris).

feeding ecology and diet

Forage low in vegetation in a marsh or on the ground. Their food consists of invertebrate animals (especially insects), grain, and other seeds.

reproductive biology

Males commonly are simultaneously paired to up to six females; females are not monogamous, and will solicit copulation from males other than their principal mate. Females build the nest, which is a bulky cup of woven vegetation, commonly woven to several stalks of emergent vegetation in marshes. Three to five eggs are laid in May–July. Incubation 12–13 days; fledging at about 12 days. Usually single brooded, but replacement clutches may be produced.

conservation status

Not threatened. Yellow-headed blackbirds are common, and data indicate that their numbers are stable.

significance to humans

Considered an agricultural pest in some areas. They commonly gather in large roosts in urban areas in winter, where their droppings may be a concern for public health.

Yellow-hooded blackbird

Agelaius icterocephalus

taxonomy

Oriolus icterocephalus Linnaeus, 1766, Cayenne. Two geographically distinct forms are recognized.

other common names

French: Carouge à capuchon; German: Gelbkopfstärling; Spanish: Turpial de Agua.

physical characteristics

6.5–7 in (17–18 cm); female 0.8–1.1 oz (24–31 g), male 1.1–1.4 oz (31.5–40 g). Sexually dimorphic in color. Males are black with a yellow hood and black around the bill. Females are grayish olive above, and have a brownish belly, flecked with black, and a dusky yellow hood, with the yellow on the throat and the stripe over the eye brighter.

distribution

Resident of northern South America and along the Amazon River, from northern Colombia to central Brazil, east to northeastern Peru.

habitat

Freshwater marshes and tall, wet grasslands. Although characteristically a bird of the lowlands, they are found to about 8,500 ft (2,600 m) in the Andes of Colombia.

behavior

Territorial during the breeding season. Males display to other males using a "song-spread" display, much like that of the North American red-winged blackbird. Males approach females with a distinctive fluttering flight; receptive females follow males to nests constructed by the males. During all seasons they are commonly seen in small loose flocks; large numbers may congregate in roosts. During the breeding season, males form colonies in marshes and start building nests.

feeding ecology and diet

Yellow-hooded blackbirds feed in marshes or in pastures, where they eat seeds and capture invertebrates.

reproductive biology

Successful males mate with up to five different females in a single season. Males build a nest in emergent aquatic vegetation; the female adds the lining to the nest after the pair is formed. Mated males stay with their mate until incubation begins, then they build another nest and seek an additional mate. Generally 2–3 eggs are laid in May–October in Trinidad and October–November in Venezuela. Incubation 10–11 days; young fledge at about 11 days.

conservation status

Not threatened. They are locally common.

significance to humans

They commonly forage in rice paddies and other agricultural lands, and cause some crop damage.

Red-winged blackbird

Agelaius phoeniceus

taxonomy

Oriolus phoeniceus Linnaeus, 1766, Charleston, South Carolina. Presently, 20 geographically discrete forms are recognized.

other common names

English: Cuban red-winged blackbird; French: Carouges à épaulettes; German: Rotschulterstärling; Spanish: Tordo Alirrojo, Tordo Capitán, Mayito de la Diénaga, Sargento.

physical characteristics

7–9.5 in (18–24 cm); female 1–1.9 oz (29–55 g), male 1.9–2.9 oz (53–81 g). Sexually dimorphic in color. Males black with red epaulets edged with a yellow bar. Young males are dark brown

and heavily streaked below with some red in the wing. Males in their second year resemble older males, but many of their feathers are edged with brown. Females are streaked with dark brown. Juveniles resemble females.

distribution

Breeds from eastern Alaska and Great Bear Lake, east to James Bay, southern Quebec, and southwestern Newfoundland, south to Costa Rica; local in Central America, and absent as a breeder from western Mexico and central and southern Baja California. Winters from southern Canada south to Costa Rica, including western Mexico and Baja California.

habitat

Marshes and rank, moist thickets.

behavior

Territorial during the breeding season. Males defend a territory with songs and chasing. In winter, found in flocks, often enormous ones that contain several different species of blackbirds as well as European starlings (Sturnus vulgaris).

feeding ecology and diet

Forage low in vegetation or on the ground.

reproductive biology

Males are commonly simultaneously paired to several females. Females build the nest, which is a bulky cup of woven vegetation, commonly woven to several stalks of emergent vegetation in marshes. Clutch size is smaller in the south than in the north and ranges in size from 4 to 5 eggs, which are laid from May to mid-June. Incubation 11–13 days; fledging at about 11–12 days. Usually single brooded, but replacement clutches may be produced.

conservation status

Not threatened. One of the most abundant North American birds.

significance to humans

Considered an agricultural pest in many areas. Much effort and money have been expended in attempts to control blackbird roosts, and consequently humans are one of the major causes of adult mortality.

White-browed blackbird

Sturnella superciliaris

taxonomy

Trupialis superciliaris Bonaparte, 1851, Matto Grosso, Brazil.

other common names

English: Red-breasted blackbird; French: Sturnelle à sourcils blancs; German: Rotbruststärling, Weissbrauenstärling; Spanish: Pecho Colorado, Pechicolorado Chico.

physical characteristics

6.5–7 in (17–18 cm); female 1.4 oz (39.5 g), male 1.9 oz (53 g). Sexually dimorphic in color. Males are black with a bright red throat, breast, and shoulders (visible in flight), and a prominent white stripe behind the eye. Females have a pale buff stripe above the eye, dark brown crown stripes and a dark brown stripe behind the eye, with a brown, mottled back, and buff undersides, with streaks on the throat and belly, but not on the breast, which is variously tinged with pink.

distribution

Resident from southeastern Peru and west-central Brazil south to northern Argentina, and also in the lowlands of eastern Brazil. Withdraw from the southernmost part of the range in Argentina in winter. Found from sea level to over 8,200 ft (2,500 m).

habitat

Grasslands and damp pastures.

behavior

Gregarious, especially in the nonbreeding season, but they often nest in loose colonies. Territorial during the breeding season. Males have a spectacular butterfly-like aerial display: they fly to a height of over 66 ft (20 m) over their territory, then parachute downward while singing. They also sing from the ground. Females are difficult to see.

feeding ecology and diet

Forage on ground where they take seeds and insects. They often feed among livestock and agricultural fields.

reproductive biology

Monogamous. Nest is placed on the ground, with grass pulled over it, so that it is not visible from above. Commonly 3–5 eggs are laid in October–January. Data on incubation and fledging not available.

conservation status

Not threatened. Locally common throughout; increasing in numbers and expanding its range in response to the spread of cultivation of rice and other grain crops.

significance to humans

May cause local damage to crops.

Long-tailed meadowlark

Sturnella loyca

taxonomy

Trupialis loyca Bonaparte, 1851, Peru. At present, four geographically discrete forms are recognized.

other common names

French: Sturnelle australe; German: Langschwanz-Soldatenstärling; Spanish: Loica Común.

physical characteristics

9.5–10 in (24–25.5 cm); 4 oz (113 g). The sexes are similar in color, but the females are somewhat duller. The throat, breast, and belly are red, and there is a dash of red from above the eye to the bill. There is a white line running from the top of the eye back to the nape.

distribution

Resident in western South America from central Chile and in foothills and intermontane valleys in western Argentina, and in the steppes of central Argentina south to Tierra del Fuego and the Falkland Islands. Some Chilean and Patagonian birds move northward in winter.

habitat

Arid grassy areas with scattered shrubs; pastures and cultivated fields.

behavior

Territorial during the breeding season. Males defend a territory with songs and chasing; they generally sing from bushes or trees. Long-tailed meadowlarks typically perch in trees in flocks and behave more like many other blackbirds rather than other meadowlarks, which characteristically spend most of their time on the ground. In winter, solitary or found in small groups.

feeding ecology and diet

Forage on ground where they take seeds and insects.

reproductive biology

Monogamous. Nest is a domed cup placed on the ground (except in the Falkland Islands where the nest may be above the ground, built on a pedestal of tussock grass). Generally 3–5 eggs are laid in September–January (August–November in Falklands). Data on incubation and fledging not available. May be double brooded.

conservation status

Not threatened. Common throughout their range.

significance to humans

None known.

Western meadowlark

Sturnella neglecta

taxonomy

Sturnella neglecta Audubon, 1844, Old Fort Union, North Dakota.

other common names

French: Sturnelle de l'ouest; German: Wiesenstärling; Spanish: Triguera de Occidente, Pradero Occidental.

physical characteristics

8.5–9.5 in (21.5–24 cm); female 3.2 oz (89 g), male 4 oz (115 g). Sexes alike in color. Throat and underparts bright yellow, with a black V on the breast; yellow stripe over the eye; back, wings, and tail mottled with brown; outermost tail feathers white.

distribution

Breeds from central British Columbia and Alberta east to southern Ontario, and south through the Great Plains to central

Pairs are territorial, and individuals of both sexes defend their territories with songs and displays (tail-flicking and a fluttering

"bill-up" flight). In winter, pairs may gather into small groups, flocking sometimes with grackles and cowbirds. Sometimes roosts in dense cane with other blackbirds.

feeding ecology and diet

Forages mainly on the ground, commonly on lawns and other cleared areas. When foraging in trees, they pick insects and larvae from foliage, and drink nectar from flowers. Their diet consists of seeds, fruits, nectar, and invertebrates (especially insects).

reproductive biology

Monogamous. The nest is an open cup placed in a bush or tree; both sexes assist in building the nest. Three to four eggs are laid in April–July. Incubation about 14 days; information on fledging not available. Single brooded.

conservation status

Not threatened. Common, and expanding its range southward into the Pacific slope of Guatemala, El Salvador, and northern Costa Rica, probably as a consequence of clearing of land for agriculture.

significance to humans

They eat the ripening ears of maize, and are considered to be agricultural pests.

Great-tailed grackle

Quiscalus mexicanus

taxonomy

Corvus mexicanus Gmelin, 1788, Veracruz, Mexico. At least eight geographically discrete forms recognized.

other common names

French: Quiscale à longue queue; German: Dohlengrackel; Spanish: Clarinero, Zanate Grande, Zanate Mayor.

physical characteristics

10.5–18.5 in (26.5–47 cm); female 3.6–4.7 oz (102–132 g), male 6.2–8.9 oz (175–253 g). Sexually dimorphic in color. Males black glossed with purple on the head, becoming blue on the belly and back, and a yellow eye. They have a long keel-shaped tail. Females brown, with pale brown throat and stripe above the eye; geographically variable. Juveniles resemble females.

distribution

Resident in central California, central Colorado, and eastern Iowa, south to the Gulf coast south through Mexico and Central America to the coast of northwestern Venezuela and south to northwestern Peru. Some individuals from northern populations move south in winter.

habitat

Pastures, agricultural lands, second-growth scrub, mangrove forests, and secondary forests to 7,500 ft (2,300 m).

behavior

Territorial during the breeding season. Males defend a territory with songs, "rough out" and "bill pointing" displays, and chasing. In winter, found in flocks.

feeding ecology and diet

Forage mostly on ground or low in vegetation. Foods taken vary seasonally, but diets consist principally of animal matter (especially grasshoppers and other insects).

reproductive biology

Successful males mate with several different females in a single season. Females build the bulky, cup-shaped nest, which is placed above ground, generally as high as the vegetation permits. Generally 2–4 eggs are laid in January–July. Nesting commences earlier and clutch sizes are smaller in the south than in the north. Incubation takes 13–14 days; fledging about 16–19 days. Two broods may be produced in a single season.

conservation status

Not threatened. Widespread and common, and its range is rapidly expanding northward in the Great Plains.

significance to humans

They may be considered agricultural pests in some areas; however, they eat many insects that could cause crop damage.

Rusty blackbird

Euphagus carolinus

taxonomy

Turdus carolinus Müller, 1776, Carolina. Two geographically discrete forms recognized.

other common names

French: Quiscale rouilleux; German: Roststärling; Spanish: Tordo Canadiense.

physical characteristics

8–9 in (20.5–23 cm); female 1.7–2.7 oz (47–76.5 g), male 1.6–2.8 oz (46–80.5 g). Sexes similar in color. Entirely black with a greenish or sometimes purplish gloss, a square-tipped tail, thin bill, and pale yellow eyes. Juveniles brownish, with a paler brown throat and stripe above the eye, and sometimes with the black flecking on the undersides.

distribution

Breeds from western Alaska east across northern Yukon, central Northwest Territories, northern Manitoba and north-central Labrador and Newfoundland south to southern Alaska, northwest British Columbia, central Saskatchewan, southern Ontario, northeastern New York, and western Massachusetts. Winters from the northern states east of the Rockies, south to the Gulf coast and northern Florida, west to eastern Texas.

habitat

Moist woodlands (primarily coniferous) and bogs. In winter, found in open, wet woodland, pastures, and cultivated fields.

behavior

Territorial during the breeding season. They are usually solitary nesters, but small colonies are not infrequent in Newfoundland and Labrador. Males defend a territory with songs and chasing. In winter, usually found in flocks; when alarmed, they fly to the nearest bush or tree. In winter, they may flock with other species of blackbirds, but flocks of only rusty blackbirds are not uncommon.

feeding ecology and diet

Forage mostly on ground or low in vegetation. Their food is principally insects, but they will take small birds, and eat some grain and other seeds.

reproductive biology

Monogamous. The nest is a bulky cup of twigs, grass, and other plant matter, which may be placed on the ground or as high as 23 ft (7 m). Generally 4–5 eggs are laid in May–June. Incubation about 14 days; fledging about 12 days. Single brooded.

conservation status

Not threatened. Widespread and common, but numbers declining.

significance to humans

None known.

Baywing

Agelaioides badius

taxonomy

Agelaius badius Vieillot, 1819, Parguay. There are two geographically discrete forms. Many treat the pale baywing (A. fringillarius) as a third subspecies.

other common names

English: Bay-winged cowbird; French: Vacher à ailes baies; German: Braunkuhstärling; Spanish: Músico, Tordo Mulato.

physical characteristics

7–7.5 in (18–19 cm); 1.4–1.8 oz (41–50 g). Sexes similar in color. Olive-gray, dusky between the bill and the eye, blackish tail, and blackish wings broadly edged with rufous. They have a short conical bill. Juveniles resemble adults.

distribution

Resident in northeastern Brazil, and northern and eastern Bolivia south through western and central Paraguay, Uruguay, to central Argentina.

habitat

Open, wooded, or shrubby terrain and adjacent pastures. Found to 9,500 ft (2,880 m) in Bolivia.

behavior

This is a social blackbird, typically found in small groups of four to 25 individuals. They roost communally. Baywings sing

frequently, but unlike most blackbirds, song is not accompanied by displays. They sing from a perch, and often from near the nest.

feeding ecology and diet

They feed both in trees, where they glean for insects, and on the ground, generally near woodland or shrubby cover.

reproductive biology

Socially monogamous. Baywings most commonly use the abandoned nest of another species. Covered nests are preferred, such as the nests of ovenbirds (Furnariidae); they will nest in woodpecker holes and in nest boxes, and they do sometimes build their own cup-shaped nests. Clutch size is generally 4–5 eggs, which are laid late November–early January. They are cooperative breeders and one or more "helpers" will help raise the young. They are frequently parasitized by screaming cowbirds (Molothrus rufoaxillaris), making it difficult to obtain accurate information on clutch size, and incubation and fledging times because the baywings often suspend nesting to reduce parasitism.

conservation status

Not threatened. They are common to fairly common.

significance to humans

None known.

Brown-headed cowbird

Molothrus ater

taxonomy

Oriolus ater Boddaert, 1783, Carolina. Three geographically discrete forms are recognized.

other common names

French: Vacher à tête brune; German: Braunkopf-Kuhstärling; Spanish: Vaquero Cabecicafé, Tordo Negro.

physical characteristics

6.5–7.5 in (16.5–18 cm); female 1.1–1.8 oz (30.5–51 g), male 1.1–2 oz (32.5–58 g). Sexually dimorphic in color. Males black with a brown head; the black is greenish-glossed, and purple-glossed on the neck. Females are entirely brown, with the throat somewhat paler. Juveniles resemble females, but have scaly backs and boldly-streaked underparts. The bill is short and conical.

distribution

Breeds from central and northeastern British Columbia, Alberta, central Saskatchewan and southern Manitoba, east through central Ontario and Quebec to Newfoundland, and south to the Isthmus of Tehuntepec, Mexico. Resident from Nova Scotia, Maine, Illinois, eastern Kansas, west across Oklahoma, Texas, southern New Mexico, and Arizona, and along the Pacific coast north to southwestern British Columbia; does not breed in southern Florida, on the Gulf lowlands of eastern Mexico, or the lowlands of southwestern Mexico. Winters along the Gulf of Mexico coast of Mexico, and on the Pacific coast from Jalisco south to the Isthmus of Tehuntepec, and in southern Florida.

habitat

Open woodlands and deciduous forest edge; in migration and winter in open areas, cultivated lands, fields, pastures, and scrub.

behavior

Males display with a full "song-spread" display. In some populations, where they are monogamous, males guard their mates. Females lay their eggs in the nests of other species of birds. They usually do this early in the morning, and remove one of the host's eggs, replacing it with one of theirs. In winter, found in flocks that usually contain several different species of blackbirds as well as European starlings (Sturnus vulgaris).

feeding ecology and diet

Forage low in vegetation or on the ground, often near the feet of grazing ungulates, where they pick up insects that have been flushed. During the nonbreeding season, they eat primarily grain.

reproductive biology

In some areas, males are monogamous; in others they commonly are simultaneously paired to two or more females. No nest is built, but they have been recorded to have parasitized the nests of more than 220 host species (144 of which have been seen to fledge cowbird young). Females do not lay clutches in the usual sense, but one egg is produced each 1–7 days, interrupted by 2 days when no eggs are produced; eggs are laid from March to early-August. Incubation 10–12 days; fledging at 8–13 days.

conservation status

Not threatened. Common to abundant, and has benefited from the clearing of land for agriculture, and wild bird feeding.

significance to humans

It is considered a pest in feedlots and grain fields. Its brood parasitic habits have caused serious declines in some populations of songbirds.

Bobolink

Dolichonyx oryzivorus

taxonomy

Fringilla oryzivora Linnaeus, 1758, South Carolina.

other common names

French: Goglu de pré; German: Bobolink; Spanish: Charlatán, Triste-pia.

physical characteristics

6–7 in (15–17.5 cm); female 0.9–1.6 oz (26.5–44.3 g), male 1–2 oz (28.5–56.3 g). Sexually dimorphic in color. Males black face and underparts, light yellow on the back of head and nape, pale grayish white rump, wings black with pale edges to some of the feathers, white scapulars, and a white-tipped black tail. Males in winter, females, and juveniles brown or yellow ochre, with a pale stripe above the eye, streaked and mottled back, pale throat, and varying amounts of streaking on the breast and flanks.

distribution

Breeds from southwestern Newfoundland west to central British Columbia, south to central Colorado, northern

Missouri, and central Virginia. Winters in the pampas of southwestern Brazil south to central Argentina.

habitat

Breeds in moist grassy meadows or old fields. Originally wintered in grasslands and marshes, but now commonly is found in rice fields.

behavior

Territorial during the breeding season. Males defend a territory with flight-songs, fights and chases. In migration and winter, often occurs in large flocks.

feeding ecology and diet

Forage on the ground. Young are fed insects and other invertebrates. Winter diet is mostly various grains and seeds.

reproductive biology

Males are paired simultaneously with several females. Females select the nest site and build the nest, which is an open cup of woven grass and other vegetation, placed on the ground, often at the base of a forb. Three to seven (commonly five) eggs are laid from mid-May to mid-July. Incubation 12–14 days; fledging at 10 or 11 days. Single brooded, but replacement clutches may be produced.

conservation status

Not threatened. Widespread and locally common, but numbers declining in many areas. Destruction of suitable habitat in both their wintering and breeding range may be affecting numbers.

significance to humans

It is considered an agricultural pest outside of its breeding range.

Resources

Books

American Ornithologists' Union. Check-list of North American Birds. 7th ed. Washington, DC: American Ornithologists' Union, 1998.

Collar, N.J., L.P. Gonzaga, N. Krabbe, A. Madroño Nieto, L.G. Naranjo, T.A. Parker III, and D.C. Wege. Threatened Birds of the Americas. Cambridge, United Kingdom: International Council for Bird Preservation, 1992.

Jaramillo, A., and P. Burke. New World Blackbirds: The Icterids. Princeton: Princeton University Press, 1999.

Orians, G. Blackbirds of the Americas. Seattle: University of Washington Press, 1985.

Periodicals

Lanyon, S.M. "Polyphyly of the Blackbird Genus Agelaius and the Importance of Assumptions of Monophyly in Comparative Studies." Evolution 10 (1994): 679–693.

Nero, R.W. "A Behavior Study of the Red-Winged Blackbird I: Mating and Nesting Activities." Wilson Bulletin 68 (1956): 4–37.

Johnson, K.P., and S.M. Lanyon. "Molecular Systematics of the Grackles and Allies, and the Effect of Additional Sequence (Cyt b and ND2)." Auk 116 (1999): 759–768.

James David Rising, PhD

Grzimek's Animal Life Encyclopedia