Athene cuniculariaburrowing owl

Geographic Range

The range of the burrowing owls includes non-breeding, year-round, and breeding populations. Non-breeding populations range from Central America (Honduras) northward along the east coast of Central America into east Texas and Louisiana. They also continue northward from the west coast of Central America to just south of the borders of Arizona and New Mexico. From here, the year-round populations reside. The year-round population extends north through Baja peninsula and southern California, eastward to central Arizona and New Mexico and northern Texas. Finally, the breeding range extends north through the prairies of southern Alberta, Saskatchewan and Manitoba Canada. There is a resident population in central and south Florida, and Caribbean Islands. (Brinkley and Tufts, 2007; Haug, et al., 2014; Manning, 2011; Peterson, 1980; Sarno, et al., 2012)

Habitat

Burrowing owls’ habitats are open areas that are open-canopied, with sparse ground vegetation and few trees. Habitats generally include agricultural lands, deserts, grasslands, prairies, and plains. This can also include urban vacant lots, airports, golf courses, and fairgrounds. Burrowing owls are commonly found in burrows abandoned by other animals such as badgers (Taxidea taxus), ground squirrels, desert tortoise (Gopherus agassizii), gopher tortoises (Gopherus polyphemus), prairie dogs (Cynomys), coyotes (Canis latrans) and foxes. Owls in the Florida population often dig their own burrows. The burrows are generally 3 to 3.7 meters in length, angled downwards, so that the sunlight cannot reach the bottom of the burrow. (Barclay, et al., 2011; Haug, et al., 2014; Manning, 2011)

Physical Description

Both male and female burrowing owls weigh in at 127 to 255 grams. They are small in stature measuring between 19 to 25 cm tall and have a wingspan roughly 53 to 61 cm. Compared to their body size they have long legs and a short tail. They have brilliant yellow eyes that are arched by white eyebrows and no ear tufts. Adult plumage is brown with barred stripes on the chest, a white chin stripe and spots on the back. Juveniles have no bars on the chest and few spots on the back. Burrowing owl chests are dingy white to a buff white. Sexual dimorphism, if it exists, is minimal. Some studies report that males, on average, weigh 3% more than females. However, this difference is insubstantial because of the wide ranges in adult weights. (Brinkley and Tufts, 2007; Haug, et al., 2014; Peterson, 1980)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    127 to 255 g
    4.48 to 8.99 oz
  • Range length
    19 to 25 cm
    7.48 to 9.84 in
  • Range wingspan
    53 to 61 cm
    20.87 to 24.02 in

Reproduction

Burrowing owls breed annually and are monogamous. Courtship can include singing, preening and a presentation of food by the male. Quick flight displays have been observed up to 30 m, followed by hovering, and a swift descent. This pattern is repeated several times. The male displays and calls the female and when she arrives, the male mounts her and copulation is completed in seconds. This sequence may be repeated. ("Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Haug, et al., 2014; Machicote, et al., 2004)

The breeding season for burrowing owls can be early February to late May, depending on the geographical region. Burrowing owls can have more than one clutch in a season but it is not normal. They can have between 2 and 12 offspring annually. Egg hatch time is 28 to 30 days with a birth mass of 8 to 9 grams. Offspring independence occurs around 53 days, and sexual maturity around 10 months. Burrowing owls defend the burrow nest, increasing their aggression as the eggs hatch. Burrow sizes vary depending on the terrestrial habitat. The average dimension of a burrow depends on the animal that excavated it. In Florida, burrows are generally dug by the owls and are approximately 1 m deep and approximately 2 to 3 m in length. Most burrows have a slight curve to them so sunlight does not reach to the nest cavity. It is thought that the male picks the burrow. ("Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Haug, et al., 2014; Machicote, et al., 2004; Welty, et al., 2012)

  • Breeding interval
    Anual
  • Breeding season
    February to May depending on location
  • Range eggs per season
    2 to 12
  • Average eggs per season
    6
    AnAge
  • Range time to hatching
    28 to 30 days
  • Range fledging age
    44 to 53 days
  • Average fledging age
    48 days
  • Average time to independence
    53 days
  • Range age at sexual or reproductive maturity (female)
    10 to 10 months
  • Range age at sexual or reproductive maturity (male)
    10 to 10 months

Parental roles for burrowing owls vary between sexes. The male’s role is to hunt, feeding himself and the female. The female lays and incubates the eggs, and takes care of all the brood work. The male will bring the food to the burrow and transfer it his mate, and she will feed herself and tear off pieces for the chicks to eat. The female will not stray from the young until they can thermoregulate. The female starts to stray farther from the burrow hunting and foraging when the chicks are around two weeks old and have become less dependent. The fledglings are independent around 44 to 53 days. ("Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Conway, et al., 2012; Haug, et al., 2014; Thiele, et al., 2013)

  • Parental Investment
  • altricial
  • male parental care
  • female parental care
  • pre-fertilization
    • provisioning
    • protecting
      • male
      • female
  • pre-hatching/birth
    • provisioning
      • male
    • protecting
      • male
      • female
  • pre-weaning/fledging
    • provisioning
      • male
      • female
    • protecting
      • male
      • female
  • pre-independence
    • provisioning
      • male
      • female
    • protecting
      • male
      • female
  • post-independence association with parents

Lifespan/Longevity

Burrowing owls live 6 to 8 years in the wild and up to 10 years in captivity. The longest know lifespan in the wild is 11 years. In the wild, two-thirds do not live to adulthood. Most mortality happens between fledging and the end of year one. A few of the causes of mortality the first year are prey density being too low, inexperience in capturing food, predators and parasites. ("BBL - Longevity Records of North American Birds", 2011; "Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Haug, et al., 2014)

  • Range lifespan
    Status: wild
    11 (high) years
  • Range lifespan
    Status: captivity
    10 (high) years
  • Typical lifespan
    Status: wild
    6 to 8 years

Behavior

Burrowing owls use abandoned burrows of colonial species such as prairie dogs (Cynomys), which cause them to have a semi-colonial existence. These owls roost in a depression in the ground or on the mound of the nest site. Males can choose a separate roosting burrow site, roosting in shrubs and trees but this is not as common. Burrowing owls generally stay on the ground or low to it, perching on the nest site mound or on a low fence post or small shrub. They walk, hop and run in search of insects and small mammals. Burrowing owls also use a flight approach to hunt prey by taking to the wing and hovering above the ground in search of prey. They also use flight to escape predators and to defend the nest site.

Burrowing owls are diurnal, active all day, but concentrate hunting activity around sunrise and sunset. This species will also spend some time during their day stretching and preening. Burrowing owls will bathe in a puddle or even a rain shower is enough for their bath. They will also take a dust bath in a shallow depression in the dirt, flicking it through their feathers to displace mites. ("Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Haug, et al., 2014; Lynch, 2007; Manning, 2011)

  • Range territory size
    0.45 to 2.4 km^2
  • Average territory size
    1.95 km^2

Home Range

The burrowing owl home range is estimated to be 45ha (Rosenberg and Haley 2004) to 240ha (Haug and Oliphant 1990). Territory around the nest ranges from 0.45 to 2.4 kilometers squared. The difference in variation in estimation of home range is probably due to several variables like the landscape, the availability of prey and how far apart the abandoned burrows are from each other. For example, in the case of an abandoned prairie dog (Cynomys) town, the distance between burrows in colonies may vary from 14m to 900m. ("Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Haug and Oliphant, 1990; Haug, et al., 2014; Rosenberg and Haley, 2004)

Communication and Perception

Adult burrowing owls have been identified as having 13 unique vocalizations, and the juvenile birds having only 3 vocalizations, consist of defense calls, food begging wines, and distress calls. Their primary song is a two-note coo-coooo or at night a co-hoo, with higher pitches than mourning doves (Zenaida macroura). The two-note song used by the male for establishment of pairs, territorial defense and premating ritual. When defending the nest they can scream, cluck and chatter. Non-vocalization methods of communication are bill snapping and a wing flap for distress. Burrowing owls have binocular vision their field of view is about 110 degrees. They are capable of turning their head 270 degrees. (Haug, et al., 2014; Peterson, 1980)

Food Habits

Burrowing owls consume a variety of insects, including: grasshoppers, crickets and beetles. Approximately 90% of their diet is arthropods. They will also eat small mammals, such as mice and ground squirrels, and small birds, like sparrows. They hunt resourcefully and can also catch snakes, lizards, bats, and earthworms. Burrowing owls have adaptable food habits because of seasonal changes that are dependent on the population density of other animals. During the brood rearing season, the females have a habit of hunting arthropods. Males can range up to 9.6 kilometers from the nest searching for food, but normally stay within 1.6 kilometers to do most of the hunting. While burrowing owls eat small mammals and birds. Depending on the prey being pursued, their style of hunting changes. Insects are pursued on the ground and sometimes are taken on the wing. When vegetation cover is variable, burrowing owls hover when hunting small mammals. (Haug, et al., 2014; Marsh, et al., 2014; Sarno, et al., 2012; Trulio and Higgins, 2012)

  • Primary Diet
  • carnivore
    • eats terrestrial vertebrates
    • insectivore
    • eats non-insect arthropods
    • vermivore
  • Animal Foods
  • birds
  • mammals
  • amphibians
  • reptiles
  • insects
  • terrestrial non-insect arthropods
  • terrestrial worms

Predation

Burrowing owls are a prey choice for other birds of prey. Such predators include: peregrine falcons (Falco pergrinus), prairie falcons (Falco mexicanus), red-tailed hawks (Buteo jamaicensis), Swainson’s hawks (Buteo swainsoni), broad-winged hawks (Buteo platypterus), Cooper’s hawks (Accipiter cooperii), bald eagles (Haliaeetus leucocephalus), and golden eagles (Aquila chrysaetos). Burrowing owls have many other predators such as foxes, coyotes (Canis latrans), domestic cats (Felis catus) and dogs (Canis lupus familiaris), badgers (Taxidea taxus), Virginia opossums (Didelphis virginiana), bobcat (Lynx rufus), cougar (Puma concolor), weasels, skunks and humans (Homo sapiens). Humans are predatory because farmers fill in the burrows in their pastures. Reptiles also can take eggs from the nest. When attacked or forced to defend the nest, burrowing owls can scream, cluck and chatter. Non-vocalization methods of communication are bill snapping and a wing flap for distress. ("Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Haug, et al., 2014; Manning and Kaler, 2011; Sarno, et al., 2012)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Burrowing owls have an important role in maintaining a balance in populations of their prey, small mammals and insects, and also serve and prey themselves. Some studies suggest populations are declining which may cause a ripple effect through their ecosystem. They host parasites such as: lice (Colpocephalum pectinatum), (Strigiphilus speotyti), fleas (Echidnophaga gallinacean), (Pulex irritans), (Aetheca wagneri), mites (Colpocephalum pectinatum), and gapeworm (Cyathostoma americana??). Ground squirrels, desert tortoises (Gopherus agassizii), gopher tortoises (Gopherus polyphemus), prairie dogs (Cynomys), have a mutualistic relationship with burrowing owls. ("Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Haug, et al., 2014; Marsh, et al., 2014)

  • Ecosystem Impact
  • creates habitat
Mutualist Species
Commensal/Parasitic Species
  • lice (Colpocephalum pectinatum, Strigiphilus speotyt), fleas (Echidnophaga gallinacean, Pulex irritans, Aetheca wagneri), mites (Colpocephalum pectinatum), and gapeworm (Cyathostoma americana)

Economic Importance for Humans: Positive

Birding festivals in late February celebrate burrowing owls and whooping cranes (Grus americana), bringing birders form around the country to watch these birds. This generates an economic value to the communities that put on these festivals. There are also online burrowing owl camera websites to observe them. Cape Coral Friends of Wildlife (http://www.ccfriendsofwildlife.org/burrowing%20owl/) dedicated to the protection, prevention and education of these owls puts out a map and engagement rules to view burrowing owls in the county they resides

Economic Importance for Humans: Negative

There are no known adverse effects of burrowing owls on humans.

Conservation Status

According to the IUCN Red List, the burrowing owl populations are large and not vulnerable, currently listed as a species of Least Concern. The U.S. Fish & Wildlife Service does not have the burrowing owl listed under the Endangered Species Act. The main threat to these owls is the loss of habitat due to encroachment of humans. Some studies suggest populations are declining, which may cause a ripple effect through their ecosystem. However in some cases the encroachment of humans has deforested areas and created pastureland, which has increased the burrowing owl’s range. ("Species assessment for Western burrowing owl (Athene cunicularia hypugaea)", 2004; Haug, et al., 2014; Marsh, et al., 2014)

Contributors

Shane Brandes (author), Radford University, Karen Powers (editor), Radford University.

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.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

crepuscular

active at dawn and dusk

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.

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

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

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

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.

female parental care

parental care is carried out by females

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

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).

male parental care

parental care is carried out by males

migratory

makes seasonal movements between breeding and wintering grounds

monogamous

Having one mate at a time.

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.

saltatorial

specialized for leaping or bounding locomotion; jumps or hops.

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

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).

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.

urban

living in cities and large towns, landscapes dominated by human structures and activity.

visual

uses sight to communicate

References

2011. "BBL - Longevity Records of North American Birds" (On-line). Accessed October 23, 2014 at http://genomics.senescence.info/species/biblio.php?id=427.

USDI Bureau of Land Management. Species assessment for Western burrowing owl (Athene cunicularia hypugaea). none. Cheyenne, Wyoming: USDI Bureau of Land Management. 2004. Accessed October 07, 2014 at http://www.blm.gov/pgdata/etc/medialib/blm/wy/wildlife/animal-assessmnts.Par.52462.File.dat/WesternBurrowingOwl.pdf.

Barclay, J., N. Korfanta, M. Kauffman. 2011. Long-term population dynamics of a managed burrowing owl colony. The Journal of Wildlife Management, 75: 1295-1306.

Brinkley, E., C. Tufts. 2007. National Wildlife Federation Field Guide to Birds of North America. New York City: Sterling Publishing Company.

Conway, M., C. Nadeau, C. Conway. 2012. Intraspecific in reproduction traits of burrowing owls. The Jounal Ethology, 30: 395-402.

Haug, E., B. Millsap, M. Martell. 2014. Burrowing owl: Athene cunicularia. The Birds of North America Online, 061: 1. Accessed September 03, 2014 at http://bna.birds.cornell.edu/bna/species/061/articles/introduction.

Haug, E., L. Oliphant. 1990. Movements, activity patterns, and habitat use of Burrowing Owls in Saskatchewan. Journal of Wildlife Management, 54: 27-35.

Lynch, W. 2007. Owls of the United States and Canada: A Complete Guide to Their Biology and Behavior. Baltimore, Maryland: Johns Hopkins University Press.

Machicote, M., L. Branch, D. Villarreal. 2004. Burrowing owls and burrowing mammals: Are ecosystems engineers interchangeable as Facilitators?. Oikos, 106: 527-535.

Manning, J. 2011. Factors affecting detection probability of burrowing owls in southwest agroecosystem environments. The Journal of Wildlife Management, 75: 1558-1567.

Manning, J., R. Kaler. 2011. Effects of survey methods on burrowing owl behaviors. The Journal of Wildlife Management, 75: 525-530.

Marsh, A., T. Wellicome, E. Bayne. 2014. Influence of vegetation on the nocturnal foraging behavior and vertebrate prey capture by endangered burrowing owls. Avian Conservation and Ecology, 9/1: 2 (9pp.).

Peterson, R. 1980. North American Birds. Boston: Houghton Milffin Company.

Rosenberg, D., K. Haley. 2004. The ecology of burrowing owls in the agroecosystem of the Imperial Valley, California. Studies in Avian Biology, 27: 120-135.

Sarno, R., P. Nixon, B. Mealey, R. Concoby, R. Mrykalo, M. Grigione. 2012. Suitability of translocation sites for Florida burrowing owls: Prey availability and diet. Southeastern Naturalist, 11: 755-764.

Thiele, J., K. Bakker, C. Dieter. 2013. Multiscale nest site selection by burrowing owls in western South Dakota. The Wilson Journal of Ornithology, 125: 763-774.

Trulio, L., P. Higgins. 2012. The diet of western burrowing owls in an urban landscape. Western North American Naturalist, 73: 348-356.

Welty, J., J. Belthoff, J. Egbert, H. Schwabl. 2012. Relationships between yolk androgens and nest density, laying date, and laying order in western burrowing owls (Athene cunicularia hypugea). Canadian Journal of Zoology, 90: 182-192.