Animal Diversity Web

Diversity

Larks belong to the order Passeriformes, sub-order Passeri and family Alaudidae. Currently there are 17 recognized lark genera and 91 species.

Larks are small to medium-sized birds (11 to 19 cm in length) that reside in open countryside from desert to alpine tundra. They vary in color from light tan to reddish and tend to blend in well with the soil and vegetation in their chosen habitat.

Larks (particularly sky larks (Alauda arvensis)) have provided inspiration for many poets with their complex and beautiful songs. They are primarily Old World inhabitants. Horned larks (Eremophila alpestris) are the only native lark species in North America. (Dean, et al., 1992; Payne, 2003; ; Simms, 1992; Trost, 2001)

Geographic Range

Larks primarily live in the Old World. Fifty-seven percent of lark species are found in Africa, 19 percent in Africa and Eurasia, 16 percent in Asia, 6 percent in Eurasia and 1 percent in the New World. Horned larks (Eremophila alpestris) are the only lark species native to North America. Skylarks (Alauda arvensis) were introduced to Vancouver Island in British Columbia, Canada and can still be found there, and occasionally in Washington state. Skylarks were also introduced to Australia and New Zealand. (Campbell and Lack, 1985; Campbell, et al., 1997; Dean, et al., 1992; Simms, 1992)

• Biogeographic Regions
• nearctic
  • introduced
  • native
• palearctic
  • native
• oriental
  • native
• ethiopian
  • native
• neotropical
  • native
• australian
  • introduced
  • native

• Other Geographic Terms
• holarctic
• cosmopolitan

Habitat

Larks inhabit open countryside in both temperate and tropical regions. Their habitat includes: shrubland, savana, desert, tundra, grassland and farmland. Larks can be found in habitats from coastal areas at sea level to mountainous areas at an elevation of 4000 m. (Campbell and Lack, 1985; Campbell, et al., 1997; Dean, et al., 1992; Mead, 1985; Simms, 1992)

• Habitat Regions
• temperate
• tropical
• terrestrial

• Terrestrial Biomes
• tundra
• desert or dune
• savanna or grassland
• mountains

• Other Habitat Features
• agricultural

Physical Description

Larks are small- to medium-sized birds (11 to 19 cm long, 15 to 75 g) with fairly long legs, wings and tail. Most have long straight claws on their hind toes. The length of the claw depends on the bird’s habitat; longer claws are found on birds that live in areas with soft ground and some vegetation, shorter claws and toes are found on species that live in areas with harder ground. Their brown plumage (ranging from light tan to reddish) is often cryptic and matches the soil color. Some species have crests or tufts of feathers on their head. Sexes resemble each other, but males are usually larger and may have brighter, more distinct color and marking than females. Bill shape and length varies between species and can be a good indication of feeding ecology. Razo larks (Alauda razae) show sexual dimorphism in bill length. The male’s bill is 20 percent longer than the female’s, which suggests that males and females exploit different food sources. Larks molt once or twice per year depending on the species. Juveniles have less distinct coloring and patterns than adult birds. (Campbell and Lack, 1985; Dean, et al., 1992; Mead, 1985; Simms, 1992)

• Other Physical Features
• endothermic
• bilateral symmetry

• Sexual Dimorphism
• male larger
• sexes colored or patterned differently
• male more colorful

Reproduction

Although there have been some observations of polygyny, larks are largely monogamous. Females do the majority of the nest building, incubation and brooding, and both adults take part in feeding the young. Males perform display flights (high undulating flight accompanied by singing), and will also display with crests, ruffle their plumage, and bow or hop up and down on the ground. Courtship feeding occurs in some species. Males sing from prominent perches; some female larks may also sing during pair formation. Larks are territorial and defend the nest site using song and flight displays.

Cooperative breeding has been observed in one species. The observed group consisted of the breeding pair and a single helper. (Campbell and Lack, 1985; Campbell, et al., 1997; Dean, et al., 1992; Mead, 1985; Simms, 1992)

• Mating System
• monogamous
• polygynous
• cooperative breeder

Larks are seasonal breeders, usually breeding during the season of highest insect and seed abundance. Larks living in areas with long breeding seasons can have two or three clutches, while those in areas with a short window of time for breeding will have only one. Larks are solitary breeders and will defend nesting territories.

Most larks are ground nesters and build open-cup nests in small, excavated hollows in the ground. Some species build domed nests and a few build nests in shrubs to allow for increased air circulation and cooling. Nests built on the ground are situated next to small clumps of vegetation, rocks, or mounds of earth for protection and shade from the sun and prevailing wind. Nests are made of grass, plant fibers, forbs, bark, dead leaves and sedges, and are sometimes lined with plant down or feathers. Eggs are smooth, white or light blue with gray or olive-brown spots and range in size from 19 to 23 by 13 to 17 mm. Clutch size is usually 3 to 5, but can be as low as one and as high as eight. The egg-laying interval is every other day. Females usually do all of the incubation and brooding, although males in some species will help. Incubation lasts 10 to 16 days; chicks hatch synchronously and are brooded for about 4 days depending on the weather. Young larks are altricial and are fed by both adults. Chicks are fed insects (and sometime seeds) and leave the nest after about 10 days. Chicks usually fledge before they can fly and continue to be fed by their parents for 18 to 20 days.

As is common among ground nesting species, most nest failure is due to depredation. Nest success is usually 30 to 60 percent, but can be as low as 10 percent. (Ali and Ripley, 1972; Campbell and Lack, 1985; Campbell, et al., 1997; Dean, et al., 1992; Mead, 1985; Simms, 1992)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization
  • internal
• oviparous

Female larks do most of the incubating and brooding of chicks (males help in some species). Incubation lasts 10 to 16 days and the altricial chicks are brooded for about 4 days after hatching. Chicks are fed insects and occasionally seeds by both parents. Adults remove fecal sacks from the nests. Nestlings usually fledge before they can fly and continue to receive parental care for 18 to 20 days.

If a predator approaches an active nest, the adults will give alarm calls and often feign injury to draw the predator away. Because many larks nest in open desert areas, chicks are often exposed to sun and heat. Adult birds will stand next to the nest to shade it during the hottest parts of the day. (Campbell and Lack, 1985; Campbell, et al., 1997; Dean, et al., 1992; Mead, 1985; Simms, 1992)

• Parental Investment
• altricial
• male parental care
• female parental care

Lifespan/Longevity

Like most small birds, larks probably live on average only two to five years. The longest living known individuals are an 8 year, 5 month old skylark (Alauda arvensis) and a 7 year 11 month old horned lark (Eremophila alpestris). Average annual mortality for skylarks is 33 percent. (Campbell and Lack, 1985; Gill, 1995; ; Trost, 2001)

Behavior

Most larks are solitary, although some will flock in agricultural fields to feed and others flock after the breeding season prior to migrating. Some larks are sedentary, others are nomadic, moving in response to rainfall and food availability and others (particularly Northern Temperate species) are long-distance migrants. Larks are usually found in low densities, but are found closer together in high quality habitat.

Larks run rather than hop along the ground and rarely perch on shrubs and trees, except occasionally to sing. Many clean by dusting, although some bath in water. Depending on the species, they molt once or twice a year. Larks that live in desert areas will stand in the shade of grass tussocks during the hottest parts of the day.

Larks are territorial and defend their territories through song and flight displays. Some species will also raise their feather crests during a display. (Campbell and Lack, 1985; Campbell, et al., 1997; Dean, et al., 1992; Gill, 1995; Mead, 1985; ; Simms, 1992)

• Key Behaviors
• terricolous
• flies
• diurnal
• motile
• nomadic
• migratory
• sedentary
• solitary
• territorial
• social

Communication and Perception

Lark flight, feeding, threat and display calls are quite simple, however, their territorial song is very elaborate. In addition to communicating through song, larks will raise the crest of feathers in their head during agonistic and courtship displays.

Larks can locate buried insects by ear while foraging. (Mead, 1985; Simms, 1992)

• Communication Channels
• visual
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Larks are omnivorous and forage on the ground. They eat many species of insects in addition to seeds, grasses, leaves, buds, fruits and flowers (especially during the winter when insects are less available). Some species will also eat snails (Gastropoda), which they break open on rocks. Larks' insect prey are diverse and include: Ephemeroptera (mayflies), Diptera (true flies), Hemiptera (true bugs), Coleoptera (beetles), Collembola (springtails), Orthoptera (grasshoppers), Lepidoptera (adult and larval moths) and Isoptera (termites). Skylarks (Alauda arvensis) in England feed on at least 47 species of insect. Desert species acquire water from their food and dew.

The shape of a Lark’s bill is adapted to its diet and feeding technique. For example, hoopoe larks (Alaemon) have long decurved bills that are used for digging for insect larvae, while calandra larks (Melanocorypha) have strong, stout bills that are used for eating seeds. Some can also locate buried insects by ear. (Campbell and Lack, 1985; Dean, et al., 1992; Mead, 1985; Simms, 1992)

• Primary Diet
• carnivore
  • insectivore
  • molluscivore
• herbivore
  • folivore
  • frugivore
  • granivore
• omnivore

Predation

Adult larks have numerous avian predators: falcons (Falconiformes), owls (Strigiformes) and shrikes (Laniidae). Adults, chicks and eggs are also taken by mammals. Common mammalian predators include: weasels (Mustelinae), skunks (Mephitinae), squirrels (Sciruidae), raccoons (Procyon lotor) and house cats (Felis domesticus). Additional nest predators include: voles and mice (Rodentia), shrews (Sorex), crows (Corvidae) and western meadowlarks (Sturnella neglecta). Up to 90 percent of lark nests may be lost to predators.

In response to nest predators, incubating females will flush silently when the predator is far from the nest; if the predator is close to the nest she will feign injury to draw it away. Young larks leave the nest early, this is thought to decrease predation and/or decrease the chance that an entire clutch is lost simultaneously.

Larks’ cryptic plumage allows them to blend in with the ground and makes it more difficult for predators to spot them; they will often avoid using patches of ground that do not match their coloration. Foraging in flocks is also thought to be an adaptation to reduce predation. (Beason, 1995; Campbell and Lack, 1985; Dean, et al., 1992; Mead, 1985; Simms, 1992)

• Anti-predator Adaptations
• cryptic

• Known Predators

  • falcons (Falconidae)
  • owls (Strigiformes)
  • shrikes (Laniidae)
  • weasels (Mustelinae)
  • skunks (Mephitinae)
  • squirrels (Sciruidae)
  • raccoons (Procyon lotor)
  • house cats (Felis domesticus)
  • voles and mice (Rodentia)
  • shrews (Sorex)
  • crows (Corvidae)
  • western meadowlarks (Sturnella neglecta)

Ecosystem Roles

As insectivores, larks affect insect populations throughout their range.

Economic Importance for Humans: Positive

Larks can be important agents in the control of agricultural pests. For example, an adult skylark (Alauda arvensis) was found with 48 weevils (Sitona lineatus) in its stomach. This particular species of weevil is a pest on peas. (Simms, 1992)

• Positive Impacts
• controls pest population

Economic Importance for Humans: Negative

Because they occasionally feed in flocks in agricultural fields, larks are recognized as agricultural pests. In the United States they will damage crops of beets, broccoli, carrots, lettuce, peas, spinach, tomatoes, alfalfa, grain, sugar beets, cantaloupe and watermelon. (Clark and Hygnstrom, 1994)

• Negative Impacts
• crop pest

Conservation Status

The IUCN lists two species of larks as critically endangered, two species as endangered and four as vulnerable. North American species are protected under the Migratory Bird Treaty Act. No larks are listed by CITES or ESA.

Declining numbers are the result of habitat loss, degradation and fragmentation, poisoning from chemicals used on crops and introduced species (especially those that are nest predators). Some species may stand to benefit from the clearing of forested areas to create pastures and arable land. ("UNEP-WCMC Species Database: CITES-Listed Species", 2003; Campbell, et al., 1997; IUCN, 2002; Mead, 1985; Simms, 1992; Threatened and Endangered Species System, 2003; U.S. Fish and Wildlife Service, date unknown)

• IUCN Red List [Link]

  Not Evaluated

Contributors

Alaine Camfield (author), Animal Diversity Web.

Kari Kirschbaum (editor), Animal Diversity Web.

References

2003. "UNEP-WCMC Species Database: CITES-Listed Species" (On-line). Accessed November 14, 2003 at http://www.cites.org/eng/resources/species.html.

Ali, S., S. Ripley. 1972. Handbook of the Birds of Indian and Pakistan, Volume 5. London: Oxford University Press.

Beason, R. 1995. Horned Lark (Eremophila alpestris). A Poole, F Gill, eds. The Birds of North America, Vol. 195. The Academy of Natural Sciences, Philadelphia, and The American Ornithologist's Union, Washington, D.C.

Campbell, B., E. Lack. 1985. A Dictionary of Birds. Vermillion: Buteo Books.

Campbell, R., N. Dawe, I. McTaggart-Cowan, J. Cooper, G. Kaiser, M. McNall, G. Smith. 1997. The Birds of British Columbia, Volume 3, Passerines, Flycatchers through Vireos. Vancouver: UBC Press.

Clark, J., S. Hygnstrom. 1994. "Horned Larks" (On-line). Prevention and Control of Wildlife Damage. Accessed October 29, 2003 at http://wildlifedamage.unl.edu/handbook/handbook/allPDF/bird_e63.pdf.

Dean, W., C. Fry, S. Keith, P. Lack. 1992. Family Alaudidae: Larks. Pp. 13-124 in S Keith, E Urban, C Fry, eds. The Birds of Africa, Vol. IV. London: Academic Press.

Gill, F. 1995. Ornithology, Second Edition. New York: W.H. Freeman and Company.

IUCN, 2002. "The IUCN Red List of Threatened Species" (On-line). Accessed October 29, 2003 at http://www.redlist.org/.

Mead, C. 1985. Larks, Wagtails and Pipits. Pp. 336-338 in C Perrins, A Middleton, eds. The Encyclopedia of Birds. New York: Facts on File Publications.

Payne, R. 2003. "Bird Families of the World" (On-line). Accessed October 27, 2003 at http://www.ummz.lsa.umich.edu/birds/Bird_Families_of_the_World.html.

Sibley, C., J. Ahlquist. 1990. Phylogeny and Classification of Birds, A study in Molecular Evolution. New Haven: Yale University Press.

Simms, E. 1992. British Larks, Pipits & Wagtails. London: Harper Collins Publishers.

Threatened and Endangered Species System, 2003. "U.S. Listed Vertebrate Animal Species Report by Taoxonomic Group" (On-line). Accessed November 14, 2003 at http://ecos.fws.gov/tess_public/TESSWebpageVipListed?code=V&listings=0#B.

Trost, C. 2001. Larks. Pp. 416-418 in C Elphick, J Dunning, D Sibley, eds. The Sibley Guide to Bird Life and Behavior. New York: Alfred A. Knopf.

U.S. Fish and Wildlife Service, date unknown. "Birds Protected by the Migratory Bird Treaty Act" (On-line). Accessed November 14, 2003 at http://migratorybirds.fws.gov/intrnltr/mbta/mbtintro.html.