Sturnella magnaeastern meadowlark

Geographic Range

Sturnella magna is found in the eastern United States, as well as parts of the southwest U.S. and Central America. The summer breeding range includes parts of southern Canada. ("Eastern Meadowlark", 1992; Campbell, 1973)

Habitat

Eastern meadowlarks breed in native grasslands, pastures, savannas, alfalfa and hay fields, cropland borders, roadsides, orchards, golf courses, airports, reclaimed strip mines, overgrown fields, and other open areas. In the western range, the breeding range also consists of tall-grass prairies and desert grassland. In the winter they are generally found in open country, cultivated fields, feedlots, and marshes. Eastern meadowlarks are generally found in habitats that are more mesic than their close relative, western meadowlarks (S. neglecta). ("Eastern Meadowlark", 1992; Elliott and Read, 1998; Lanyon, 1995)

Physical Description

Eastern meadowlarks are medium-sized songbirds, with long, slender, light gray bills and dark brown eyes. The tails are short and have rigid rectrices. The legs and toes are long. Male S. magna have grayish heads with blackish stripes, a yellow “eyebrow”, and dark crowns with a median stripe. The wings and tail are streaked and barred with dark and light brown. Males have a broad white moustachial stripe and a yellow chin, which is divided from the underparts by a broad black breast band. The underparts turn off-white on the streaked flanks and under the tail coverts. The pale undertail coverts are streaked and spotted dusky black. Females are similar to males except that they are smaller, paler, and have a narrower breast band. Males are slightly larger than females, from 21 to 25 cm in length, females are from 19 to 23 cm. Juvenile eastern meadowlarks have masked black areas and the white areas are buffish. Juveniles also have more brown plumage in the winter. Eastern meadowlark eggs are white, speckled with reddish-brown. When these birds walk, the tail constantly jerks open. These birds fly by beating their wings vigorously and then gliding. ("Eastern Meadowlark", 1992; "Birdnature.com", 2002; Campbell, 1973; Lanyon, 1995)

  • Sexual Dimorphism
  • male larger
  • sexes colored or patterned differently
  • Range mass
    90 to 150 g
    3.17 to 5.29 oz
  • Range length
    19 to 26 cm
    7.48 to 10.24 in
  • Range wingspan
    35 to 40 cm
    13.78 to 15.75 in

Reproduction

Male eastern meadowlarks are polygynous, with most males having two to three mates. Female S. magna have only one mate per breeding season, provided that the male successfully defends the territory. Males establish their territories approximately two to four weeks before females arrive. Male S. magna display their territories with flight displays and by singing. Female eastern meadowlarks choose their mates by selecting territories, which are defended by males with conspecific vocalizations. Once the pair bond forms the pair remains close together while foraging and searching for nest sites. A male S. magna defends its territory against rivals by fluffing out its plumage and pointing its bill upwards. Males guard their mates from neighboring males by constantly guarding their mate. (Campbell, 1973; "Behavior", 2005; Lanyon, 1995)

Males establish their territories in March, females arrive about two to four weeks later females. Male eastern meadowlarks rarely engage in body contact and fighting when defending their territories, however, when it does occur it can be quite severe. Pairing occurs immediately after females arrive. The "aerial chase" occurs within minutes of a female choosing a male. The female typically initiates the chase, although sometimes the chase includes two females and one male. The aerial chase consists of either a series of short flights or as brief flights interspersed with periods of posturing and rest. Additionally, the male is typically silent during the aerial chase. These chases usually carry the participants well beyond the boundaries of the male’s territory. When a female eastern meadowlark is receptive, she eventually assumes the receptive posture, at which time the male will approach, paw the female’s back and then mount. Afterwards the female remains in a semi-receptive position and flutters and shakes its plumage, chatters several times, then vigorously preens itself. The female receptive posture consists of the female elevating its bill and tail, holding its wings slightly drooped, and quivering, sometimes the female also chatters. Later on in the breeding season "jump-flights" and tee-tee-tee calls may accompany the receptive posture. However, if a male approaches when the female is not receptive, the female will use "expansion posturing" to warn off the male. Also, males and females make jump-flights before and during repeated copulation periods. A jump-flight consists of the bird jumping approximately one meter into the air and then flying several meters. Once the breeding season is over, male S. magna cease defending their territories. (Campbell, 1973; "Behavior", 2005; Francq, 1972; Lanyon, 1995)

Female eastern meadowlarks gather nest materials and build the nest. The nest consists of coarse grasses, lined with finer grasses and is constructed on the ground, typically in a shallow depression. The outside diameter of the nest ranges from 14-21 cm, the inside diameter ranges from 8-15 cm, and the inside depth ranges from 5-8 cm. Female S. magna land a distance away from the nest and then stealthily approach the nest. (Campbell, 1973; "Behavior", 2005; Lanyon, 1995)

  • Breeding interval
    Breeding first occurs in late May, with a second brood produced in late June to early July.
  • Breeding season
    Breeding occurs from late May to August.
  • Range eggs per season
    6 to 14
  • Average eggs per season
    5
    AnAge
  • Range time to hatching
    13 to 15 days
  • Range fledging age
    11 to 12 days
  • Range time to independence
    2 (low) weeks
  • Average age at sexual or reproductive maturity (female)
    1 years
  • Average age at sexual or reproductive maturity (male)
    1 years

Females incubate the eggs for 13 to 15 days, when the altricial young hatch. After the eggs hatch both the female and her mate feed the hatchlings. However, females do most of the feeding. Nestlings typically fledge 11 to 12 days after hatching, but juveniles do not become independent for at least another two weeks. The parents continue to feed the fledglings until they become independent. (Campbell, 1973; "Breeding", 2005; Lanyon, 1995)

  • Parental Investment
  • altricial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • male
      • female
    • protecting
      • female
  • pre-independence
    • provisioning
      • male
      • female
    • protecting
      • female

Lifespan/Longevity

Eastern meadowlarks have an expected lifespan of five years in the wild, which is the same as the high end of its expected lifespan in captivity. The longest know lifespan in the wild is nine years. (Lanyon, 1995)

  • Range lifespan
    Status: wild
    9 (high) years
  • Average lifespan
    Status: wild
    5 years
  • Typical lifespan
    Status: captivity
    3 to 5 years
  • Average lifespan
    Status: wild
    151 months
    Bird Banding Laboratory

Behavior

Eastern meadowlarks are social, forming loose flocks during the fall and winter. These flocks lack a social hierarchy and are simply a loose aggregation of S. magna and occasionally, S. neglecta (western meadowlarks). They use a variety of songs, calls and postures to communicate with other meadowlarks. Also, where eastern and western meadowlark ranges overlap, male eastern meadowlarks will defend against male eastern and western meadowlarks. Males typically defend their territories with posturing and aerial displays.

Both male and female S. magna often preen and stretch, especially in the early morning hours. Stretching, specifically of the legs and wings, usually follows preening. They also tend to scratch their head with their foot, which they bring up over their wing. Sturnella magna bathes in puddles and wet grass. Sturnella magna roosts on the ground in thick grass, with its head under its scapulars and its body resting on the ground. ("Behavior", 2005; Lanyon, 1995)

Sturnella magna do not migrate, except for those in the northernmost parts of their range. However, S. magna tend to form flocks during the winter. Also, those S. magna that do migrate, do so during daylight hours, and begin their migration when it begins to freeze and snow. Some of these birds may migrate over 1,000 km to their winter range. Eastern meadowlarks that migrate, leave by the end of November and return to the breeding range in March. (Francq, 1972; Lanyon, 1995)

  • Range territory size
    28 to 32 m^2

Home Range

Male S. magna establish their territories in March, and defend their territories throughout the breeding season. During the breeding season the territories change in size and shape depending on population densities, relocations of female activity centers, and changes in habitat suitability. Once the breeding season is over S. magna do not defend or maintain territories. (Francq, 1972; Lanyon, 1995)

Communication and Perception

The songs of S. magna are one of the first birdsongs of spring. Sturnella magna have a variety of vocal communications. There are begging notes, location notes, dzert, whistle, chatter, weet, primary song, flight song, female song, zeree, and tee-tee-tee. Nestlings and recently fledged juveniles use begging and location notes, which are simple high-pitched notes. These notes enable the parents to find and feed their young. The dzert call indicates mild disturbance. The whistle indicates intense excitement in males or females, such as the presence of a predator, just before a flight song, or immediately after an aerial chase or copulation. Both sexes use the chatter call to indicate excitement such as the presence of a predator or intruder. Females also chatter after copulation and in response to their mates’ primary song. Only males use the primary song, which sounds like seee-yeee, seee-yer. In the courtship period, female S. magna use the female song, during early morning preening. The alarm call of the eastern meadowlark is a short buzzy, dzert. ("Eastern Meadowlark", 1992; "Behavior", 2005; Elliott and Read, 1998; Lanyon, 1995)

Posturing and aerial chases are used to attract and pursue possible mates. Jump-flights are used to ward off males that are intruding on another male’s territory. Bill-tilting and tail- and wing-flashing are used in territorial disputes, as is expansion posturing. Expansion posturing is when individuals extend their contour feathers, spread the tail, and draws the head close to the body. Female S. magna use expansion posturing to warn off its mate when the female is unreceptive. If expansion posturing does not succeed in warning off the male, the female will hold its feathers tight against its body and point its gaping bill at the male. Male eastern meadowlarks also use expansion posturing after the formation of the pair bond. ("Eastern Meadowlark", 1992; "Behavior", 2005; Elliott and Read, 1998; Lanyon, 1995)

Food Habits

Eastern meadowlarks walk and run on the ground while foraging for food, they also forage by probing beneath the soil. Their diet varies with the season. In the spring they feed mainly on cutworms, grubs, and caterpillars. When summer comes they eat insects, primarily beetles and grasshoppers. In the winter they eat noxious weed seeds and waste grains as well as some wildfruits and occasional carrion from road-kill or predator-kills. (Campbell, 1973; Lanyon, 1995)

  • Plant Foods
  • seeds, grains, and nuts
  • fruit

Predation

Eastern meadowlarks are preyed on by hawks and falcons and occasionally by owls. They are most likely to be preyed upon by owls during the owl’s breeding season. While the owls are raising their young, they are more likely to hunt during daylight hours, in order to catch enough prey to feed the chicks. Hawks and falcons are diurnal, and often hunt in similar habitats. During their nesting season, domestic cats, dogs, foxes, coyotes, and skunks prey upon the eggs and nestlings. Eastern meadowlark coloration helps them to blend in to their grassland surroundings, they can be difficult to spot unless they are on a high perch. (Grossman and Hamlet, 1964; Lanyon, 1995)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Eastern meadowlarks are prey for larger predators and they prey on a variety of insects, including grubs and caterpillars, which could damage the surrounding vegetation. They also act to disperse the sees of plants they eat. Sturnella magna serves as a host for a variety of internal and external parasites, and for brown-headed cowbirds. Brown-headed cowbirds are obligate parasites, which lay eggs in the nests of other species of birds. ("Western Meadowlark", 2003; "Birdnature.com", 2002; Campbell, 1973; "Demography and Populations", 2005; Grossman and Hamlet, 1964; Lanyon, 1995; Stark, 1940; Taylor, 1969)

Commensal/Parasitic Species

Economic Importance for Humans: Positive

Sturnella magna eat insects that are crop pests, therefore they act to control pest populations that impact crops. (Campbell, 1973; Lanyon, 1995)

  • Positive Impacts
  • controls pest population

Economic Importance for Humans: Negative

Sturnella species eat kernels of sprouting grain, which can destroy portions of newly planted crops. ("Western Meadowlark", 2003)

  • Negative Impacts
  • crop pest

Conservation Status

According to the IUCN Red List, the U.S. Federal List, and the State of Michigan List, eastern meadowlarks have no special status. They are not threatened, likely to become threatened, or endangered. This agrees with the Audubon Society's assessment of S. magna. Eastern meadowlarks fall into the Audubon Society's green conservation status, which means that it is of low or no conservation concern. However, S. magna populations have been experiencing a significant population decline, declining by as much as 50% since 1966. ("State of the Birds: Grasslands", 2005)

Other Comments

Eastern meadowlarks are not true larks; rather they belong to the same family as blackbirds and orioles (Icteridae). There are about 18 recognized subspecies of the eastern meadowlark.

The decline of the S. magna populations could be partially due to the industrialization of agriculture, which increases the likelihood of a nest being destroyed by the agricultural machinery and the increased use of row crops which are an unsuitable habitat for these birds. Another possible cause of the decline is apparent predation by cattle. Cattle have been documented destroying nests, sometimes by accident but also by crushing eggs and nestlings with their muzzles and by removing nestlings from the nests. ("Demography and Populations", 2005; Nack and Ribic, 2005)

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Tamar Dexheimer (author), Kalamazoo College, Ann Fraser (editor, instructor), Kalamazoo College.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

biodegradation

helps break down and decompose dead plants and/or animals

carnivore

an animal that mainly eats meat

carrion

flesh of dead animals.

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

insectivore

An animal that eats mainly insects or spiders.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

migratory

makes seasonal movements between breeding and wintering grounds

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

polygynous

having more than one female as a mate at one time

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

soil aeration

digs and breaks up soil so air and water can get in

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5? N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

Cornell Lab of Ornithology. 2005. "Behavior" (On-line). Birds of North America Online. Accessed November 19, 2005 at http://bna.birds.cornell.edu/BNA/account/Eastern_Meadowlark/BEHAVIOR.html.

Birdnature.com. 2002. "Birdnature.com" (On-line). Accessed October 01, 2005 at http://www.birdnature.com/meadowlark.html.

Cornell Lab of Ornithology. 2005. "Breeding" (On-line). Birds of North America Online. Accessed November 19, 2005 at http://bna.birds.cornell.edu/BNA/account/Eastern_Meadowlark/BREEDING.html.

Cornell Lab of Ornithology. 2005. "Demography and Populations" (On-line). Birds of North America Online. Accessed November 19, 2005 at http://bna.birds.cornell.edu/BNA/account/Eastern_Meadowlark/DEMOGRAPHY_AND_POPULATIONS.html.

Cornell Lab of Ornithology. 2003. "Eastern Meadowlark" (On-line). Accessed November 13, 2005 at http://www.birds.cornell.edu/programs/AllAboutBirds/BirdGuide/Eastern_Meadowlark.html.

1992. Eastern Meadowlark. Pp. 345 in R Zeleny, ed. The World Book Encyclopedia, Vol. 13. Chicago: World Book Inc..

National Audubon Society. 2005. "State of the Birds: Grasslands" (On-line). Accessed October 11, 2005 at http://www.audubon.org/bird/stateofthebirds/grasslands.html.

2003. Western Meadowlark. Pp. 316 in M Hutchins, ed. Grzimek's Animal Life Encyclopedia, Vol. 11. Detroit: Gale Group Inc..

Campbell, B. 1973. Sturnella magna. Pp. 337 in R Holmes, ed. The Dictionary of Birds in Color. New York: The Viking Press.

Elliott, L., M. Read. 1998. Common Birds And Their Tongs. Boston: Houghton Mifflin Company.

Francq, G. 1972. Parental care of the eastern meadowlark (Sturnella magna). Kansas: Kansas State Teachers College.

Grossman, M., J. Hamlet. 1964. Birds of Prey of the World. New York: Bonanaza Books.

Lanyon, W. 1995. Eastern Meadowlark: Sturnella magna. Washington D. C.: American Ornithologists' Union.

Nack, J., C. Ribic. 2005. Apparent predation by cattle at grassland bird nests. Wilson Bulletin, 117: 56-62.

Stark, F. 1940. A study of the animal parasites of Sturnella magna magna and Sturnella neglecta of southeastern Kansas. Pittsburg, Kansas: Kansas State Teachers College.

Taylor, R. 1969. Histological study of host-parasite relations between meadowlarks (Sturnella) and Microtetrameres Sturnellae (Nematoda: Tetrameridae). Oklahoma: University of Oklahoma Graduate College.