Bobolink

Dolichonyx oryzivorus

Bobolink_male.jpg

bobolink
Jim Rathert
Family

Icteridae (blackbirds) in the order Passeriformes

Description

The male bobolink is the only North American bird that has light feathers above and dark feathers below. Breeding male upperparts are black, with a pale, yellowish-tan nape, and white along the sides of the upper back, lower back, and rump. Underparts are all black. Female's upperparts are buffy with dark streaks; the crown is dark with a central light streak, the eyebrow is light-colored, and there is a dark line behind the eye; underparts are pale buff, with streaks on the flanks. In fall and winter, the male resembles the female but is darker above. Song is a bubbly series of musical gurgles and whistles, often sounding like bob-o-link, and is frequently given during stiff-winged courtship flights. Call is a sharp pink.

Similar species: Male lark buntings are all black, except for white wing patches, and their bills are heavier and bluish gray. Meadowlarks and female red-winged blackbirds are larger than bobolinks and have longer, pointier bills. Many sparrows live in grassy habitats and have tan, brown, buffy, streaked coloration, something like the female bobolink's; they are smaller-bodied; also compare the head and neck patterns.

Key Identifiers

 

  • Breeding male all black, except for buffy nape, white along the sides of the upper back, lower back, and rump ("tuxedo worn backward")
  • Female buffy with dark streaks above; pale buff, with streaked flanks below
  • Female head: crown dark with a central light streak; eyebrow pale; a dark line behind the eye
  • Note bill shape
  • Tail feathers are sharp-pointed (spiky looking)

 

Size

Length: 7 inches (tip of bill to tip of tail).

Bobolink_immature.jpg

immature Bobolink
immature Bobolink

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Bobolink
A Bobolink perches on a plant near Eagleville, MO.

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Bobolink
Bobolink
Habitat and conservation

The bobolink's summer range is grasslands of the northern United States and southern Canada. Originally they bred in our once-vast native prairie, but with little of that habitat remaining, now they live in the hay fields, pastures, and other agricultural lands, in many cases, where prairie used to be. In late summer, they form flocks and roost in wetlands. Wintering grounds are rice fields, marshes, and pasture in southern Brazil and the remaining native pampas (grasslands) of Argentina. Each spring and fall, bobolinks travel more than 5,000 miles between winter and summer ranges, logging an estimated 12,500 miles a year. Considering that a bobolink can live to be at least 9 years old, within its lifetime, a bobolink could easily travel the equivalent of 4 or even 5 times around the earth. They navigate by sensing the earth's magnetic field and by using stars in the night sky.

Foods

Forages in grasslands, agricultural fields, and pastures for insects and seeds. The scientific name, oryzivorus, means "rice eater"; their feasting in farmers' rice and other grain fields made them unwelcome in agricultural areas. Today, this bird's numbers are much lower than in the past.

image of Bobolink Distribution Map
Distribution in Missouri

Statewide transient.

Status

As migrant, uncommon; as summer (breeding) resident, uncommon in northern Missouri (Glaciated Plains) and local in the Osage Plains. For a century, bobolinks have been protected as a migratory bird and may not be hunted. Their numbers are still declining. The breeding male's coloration inspired two now-obsolete but memorable common names: "skunk-bird" and "white-winged blackbird."

Life cycle

Male bobolinks arrive in Missouri in late April and early May, traveling in flocks. By mid- to late May, most bobolinks have passed through, and only the summer residents are present. In their courtship display, males stand, dragging their stiff tails on the ground, arch their shoulders forward, and cock their butter-colored napes skyward. They will also fly into the air and circle around, singing their jumbled songs and displaying their flashy backs. Bobolinks are polygynous (males breed with more than one female, like many other blackbirds) but also polyandrous (females breed with more than one male). Female bobolinks build their nests on the ground. A clutch comprises 3–7 eggs, which are incubated 11–14 days. After hatching, the young remain in the nest for another 10–11 days. Males help feed the young in their primary nest but also sometimes help feed the young in their secondary nests. So sometimes nests are tended by more than two adults; those extra tenders may be the extra fathers, or they may be young from the year before. When the young leave the nest, they still need help foraging and cannot yet fly; at that point, several bobolink families flock together to forage. By late summer, the male's colors have changed to resemble the female's, though darker. In August and September, they form flocks, roosting at night in wetlands along with blackbirds and swallows. Their 5,000-mile southward migration begins in mid-September. Listen for their distinctive "pink pink" or "spink, spank" as they fly over heading south.

Human connections

Formerly, bobolinks were much more abundant and were killed by rice farmers who were losing crops to large flocks. In the 19th and early 20th centuries, many bobolinks were killed and shipped to cities as meat. In their nonbreeding plumage, they were called "reed birds" or "rice birds." "Reed birds on toast" was a popular dish. Some restaurants palmed off broiled and buttered house sparrows to unwitting customers, who apparently enjoyed them just the same. In Jamaica, bobolinks were called "butter birds," since they were so plump as they migrated south. With populations still declining today, mainly due to habitat loss, it is unlikely bobolinks will ever regain their former populations. If you have fields where bobolinks breed, mow them only after the young have fledged. Bobolinks are protected as a migratory bird and may not be hunted.

Ecosystem connections

Migratory birds play a role in all the ecosystems they pass through as they travel, providing food for predators and scavengers and snatching up insects and seeds as they go.