Chondestes grammacuslark sparrow(Also: lark-sparrow)

Geographic Range

At different times of the year, the Lark Sparrow Chondestes grammacus is found in a large portion of the contiguous United States, with the exception of the east coast and a relatively small area in the northwest. The Lark Sparrow is also found in the central-southern region of Canada, and in a large portion of Mexico. During their breeding season, they shift farther to the north, and during the winter they migrate to milder climates farther to the south. (Byers et. al. 1995; Rising 1996)

Habitat

Lark Sparrows commonly breed in prairies, savannah, mesas, farmlands, open woodland, and other open areas with scattered trees and patches of bare ground. In winter and during migration they are found in similar areas, but can also be found in brushy fields and semi-arid areas. (Byers et. al. 1995; Rising 1996)

Physical Description

An adult Lark Sparrow can measure 14 to 16 cm (5.5 to 6.3 in.) in length. Its tail is long, rounded and edged with white. The adult has a distinctive light and dark pattern on its head which typically consists of a white or beige stripe on its crown, along with chestnut coloration that starts near the top of its bill. It also has chestnut coloration on its back. There is no significant difference in coloration between the male and female Lark Sparrow. The juvenile Lark Sparrow has duller coloration than the adult Lark Sparrow and has a streaked breast. The adult bird may have a tail that appears to be more brown during the spring season, due to wear and fading. Lark Sparrows which breed in the western part of its geographic range tend to have lighter coloration than those found in other parts of the geographic range. (Gough et. al. 1998; Rising 1996)

  • Range mass
    25.5 to 33.3 g
    0.90 to 1.17 oz
  • Average mass
    29 g
    1.02 oz

Reproduction

The nesting season for the Lark Sparrow goes from mid-April through the month of July. The incubation period for the egg of a Lark Sparrow is 11-12 days. The eggs are usually white, bluish white or brownish white with dark, brownish, black or purplish speckles. The female can lay between 3-6 eggs at a time, but typically yields 4 or 5 eggs. The male does not participate in building the nest or incubating the eggs. The nest is typically built on the ground in a hollow cup-shaped depression lined with grass and stems. Both male and female typically feed their young, which normally leave the nest after 6-10 days. (Byers et. al. 1995; Ehrlich et. al. 1988; Rising 1996)

  • Average eggs per season
    4
    AnAge
  • Average time to hatching
    12 days
    AnAge

Lifespan/Longevity

Behavior

While on the ground, the Lark Sparrow either walks or hops. It is easily disturbed, and usually flies to a fence or low branch when alarmed. The male sings persistently from an exposed perch, usually at the edge of a wooded area. During courtship, the male struts back and forth in front of the female, while pointing his beak up in the air, spreading his tail and fluttering his wings. During mating, a twig is often passed to the female from the male. When migrating, they usually occur in flocks either consisting of solely Lark Sparrows or often consisting of multiple species of sparrows. (Byers et. al. 1995; Rising 1996)

Communication and Perception

Food Habits

The Lark Sparrow feeds mostly on seeds and insects. Grasshoppers are a major part of its insect diet. It forages for food in open areas on the ground. (Byers et. al. 1995; Rising 1996)

Economic Importance for Humans: Positive

The Lark Sparrow feeds on grasshoppers, species of which have been known to cause significant damage to crops; therefore, the Lark Sparrow may provide some degree of pest control.

Economic Importance for Humans: Negative

Unknown.

Conservation Status

Lark sparrows are not endangered or threatened, although they are vulnerable to forested areas being cleared to make room for farmland. They have been extirpated from the state of Michigan. (Byers et. al. 1995; Rising 1996)

Contributors

Dwight Jones (author), Fresno City College, Carl Johansson (editor), Fresno City 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

acoustic

uses sound to communicate

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.

chaparral

Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.

chemical

uses smells or other chemicals to communicate

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.

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).

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.

sexual

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

tactile

uses touch to communicate

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

Byers, C., J. Curson, U. Olsson. 1995. Sparrows and Buntings. Boston: Houghton Mifflin.

Ehrlich, P., D. Dobkin, D. Wheye. 1988. The Birder's Handbook. New York: Simon & Schuster, Inc..

Gough,, G., J. Sauer, M. Iliff. 1998. "Lark sparrow" (On-line). Accessed July, 2000 at http://www.mbr-pwrc.usgs.gov/id/framlst/i5520id.html.

Rising, J. 1996. A Guide to the Identification and Natural History of The Sparrows of the United States and Canada. San Diego: Academic Press.