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.
- Biogeographic Regions
- nearctic
- neotropical
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.
- Habitat Regions
- temperate
- Terrestrial Biomes
- desert or dune
- savanna or grassland
- Other Habitat Features
- urban
- agricultural
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.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
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.
- Mating System
- monogamous
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.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- oviparous
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.
- Parental Investment
- altricial
- male parental care
- female parental care
-
pre-fertilization
- provisioning
-
protecting
- male
- female
-
pre-hatching/birth
-
provisioning
- male
-
protecting
- male
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
-
pre-independence
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
- 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.
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.
- Key Behaviors
- terricolous
- fossorial
- flies
- glides
- saltatorial
- diurnal
- crepuscular
- motile
- migratory
- sedentary
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.
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.
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.
- 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.
- 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.
- Ecosystem Impact
- creates habitat
- Ground squirrels, desert tortoise ( Gopherus agassizii ), gopher tortoises ( Gopherus polyphemus ), prairie dogs
- 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
- Positive Impacts
- ecotourism
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.
Additional Links
Contributors
Shane Brandes (author), Radford University, Karen Powers (editor), Radford University.
- 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.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- 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).
- 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.
- 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.
- agricultural
-
living in landscapes dominated by human agriculture.
- monogamous
-
Having one mate at a time.
- 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).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- 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.
- male parental care
-
parental care is carried out by males
- female parental care
-
parental care is carried out by females
- fossorial
-
Referring to a burrowing life-style or behavior, specialized for digging or burrowing.
- saltatorial
-
specialized for leaping or bounding locomotion; jumps or hops.
- diurnal
-
- active during the day, 2. lasting for one day.
- crepuscular
-
active at dawn and dusk
- motile
-
having the capacity to move from one place to another.
- migratory
-
makes seasonal movements between breeding and wintering grounds
- sedentary
-
remains in the same area
- visual
-
uses sight to communicate
- acoustic
-
uses sound 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.
- 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.
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- 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.
- 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.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
References
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.
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Manning, J. 2011. Factors affecting detection probability of burrowing owls in southwest agroecosystem environments. The Journal of Wildlife Management , 75: 1558-1567.
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.
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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 .