Geographic Range
Eagle owls primarily live in the Palearctic region, although they can travel as far
south as the Oriental Region and Ethiopian Region and as far north as the far reaches
of Siberia. They are found in North Africa, Europe, The Middle East, and Asia.
- Biogeographic Regions
- palearctic
- oriental
- ethiopian
- Other Geographic Terms
- holarctic
- cosmopolitan
Habitat
These owls can be found in many different kinds of habitats including wooded areas
(coniferous forests), warm deserts, mountain ranges, and riverbeds. They prefer to
live in rocky landscapes, especially when nesting. Eagle owls search for habitats
with adequate food supply and proper nesting sites. Their habitats vary greatly,
and they can also be found in open areas that have few trees like farmlands and grasslands.
- Habitat Regions
- temperate
- polar
- terrestrial
- Terrestrial Biomes
- tundra
- taiga
- desert or dune
- savanna or grassland
- forest
- scrub forest
- mountains
- Other Habitat Features
- suburban
- agricultural
Physical Description
Eagle owls are the largest owls in the world, and they are best known for their large,
striking, orange eyes. They are often called the Old World version of America's widely
distributed great horned owl. They have prominent ear tufts and are primarily brown-black
and tawny-buff in color. Their facial disk is heavily marked with black, gray, and
white. Their upper parts are darker than their lower parts, which have black streaks,
and their throat is white. It is interesting to note that these owls become paler
in the northeastern geographic regions and get progressively darker as you move to
the Pacific coast. Also, size tends to decrease from north to south, and east to
west.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- female larger
Reproduction
Both sexes are usually solitary but they pair up during courtship. They advertise
potential breeding sites by digging a shallow depression into the earth and emitting
a light staccato note and various clucking sounds. They also use these calls to keep
track of their mate's location. People often hear them calling to each other. They
keep the same partners for life. Eagle owls are very sensitive to their environment.
If there is not enough food resources, will mate at a much slower rate and later
into the year. When they have sufficient habitats and plentiful food, their mating
rate increases significantly.
- Mating System
- monogamous
Eagle owls form pairs in early fall and nest in late January and early February.
They prefer to nest in crevices between rocks, sheltered cliff ledges, cave entrances,
as well as abandoned nests of other large birds. Usually egg laying begins in late
winter. They usually have one batch of eggs per year ranging from one to four white
eggs. This number depends on the food availiable in their area. When the owlets
hatch, they are brooded for about two weeks. In about three weeks the young begin
to feed and swallow by themselves. By week five they can walk around the nesting
area and begin to fly about 60 days, although for only a few meters. They leave the
nest or are driven out in the fall (Sept-Nov.) Eagle owls are able to breed from
the ages of 2-31 years.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- oviparous
Once the eggs are laid, they are incubated by the female alone. The male kills prey
and feeds his mate. Once the eggs hatch, the male continues to bring food to the
female for the next two weeks. During this time the female stays at the nest protecting
her young from predators and teaching them how to eat on their own. All owls are
imprinted by their mothers, which means they will imitate the first animal they see.
This makes it difficult to release owls into captivity if they are not raised by an
owl parent. If an owl sees a human when they are born, they think they are human
too.
- Parental Investment
- male parental care
- female parental care
Lifespan/Longevity
Eagle owls have relatively long life spans once they reach adulthood. They have no
real natural enemies. In the wild, they live for approximately 20 years, but they
can live more than 60 years in captivity.
Behavior
Eagle owls are primarily solitary animals except during the mating period. They fiercely
defend their territory against other owls and will only overlap territories slightly
if food is sparce. Eagle owls prefer to stay within the same territory unless they
are forced to leave due to food shortages or if they are driven out by other owls.
Despite their large size, they are very elusive creatures, which makes them difficult
to study in their natural habitats. Eagle owls spend most of their days roosting
high in trees remaining relatively inactive. They are nocturnal and become active
at dusk and remain so throughout the night. When food is rare, they will hunt during
the day.
- Key Behaviors
- arboreal
- flies
- nocturnal
- crepuscular
- motile
- solitary
- territorial
Communication and Perception
Eagle owls are known for their loud calls. They are heard far more than they are
seen. They use their various hoots and clucks to let others know they have entered
or are entering certain territories. Different hoots represent different moods and
are easily recognizable between each member of the species. Also, eagle owls are
able to decipher the size and distance of intruders based on the intensity of their
call. They also use a low gutteral hoot to attract mates. It's interesting to note
that even though eagle owls are difficult to study, they (like other owls) cough up
what is known as an owl pellet after their stomach goes through the digestive process.
These owl pellets contain the hair, feathers, and bones of prey they were unable to
digest. These pellets are very useful to scientists because they help them understand
the food habits of these elusive birds.
- Perception Channels
- visual
- tactile
- acoustic
- vibrations
- chemical
Food Habits
Eagle owls are carnivores. They are primarily nocturnal hunters and have various
hunting techniques. They take their prey in flight or on the ground. They prefer
to hunt in open spacious locations rather than forests. Most owls are very capable
hunters and the eagle owl is no exception. Owl wings have evolved to make very little
noise when flapping. With their night vision, advanced hearing, and silent flight
they are the hit men of their territory. Their prey usually has no idea they were
being stalked. They feed on almost anything they can catch including rats, mice,
voles
,
beetles
and even large prey like
deer
fawns and
foxes
. They will also feed on other birds such as
crows
,
ducks
, and even other
owls
. Dominant prey can vary from habitat to habitat but is most often small
rodents
.
- Primary Diet
-
carnivore
- eats terrestrial vertebrates
- insectivore
- Animal Foods
- birds
- mammals
- reptiles
- insects
Predation
Once eagle owls reach adulthood, they are at a very low risk of predation. They are
at the top of the food chain in their niche. They are not a major food source for
any other species. The only time they are at risk of predation is during their early
years. They are at risk from any predator too large for them too eat. Fortunately,
the mother stays with the young for most of this period and keeps the predators at
bay. Due to their striped, spotted, and varied coloring, they are extremely well
camouflaged, especially when perching in the trees.
- Anti-predator Adaptations
- cryptic
Ecosystem Roles
Eagle owls are at the top of their food chain. They are particularly useful in keeping
the number of rodents down in their various ecosystems. The removal of this species
can cause the rodent population in a given area to grow significantly. Therefore,
they may be a keystone predator.
- Ecosystem Impact
- keystone species
Economic Importance for Humans: Positive
Eagle owls are economically beneficial to farmers that want to keep the number of
rodents down on their land. Many birdwatchers will also pay to get a glimpse of this
rare bird in its natural habitat as well as in zoos.
- Positive Impacts
- ecotourism
- research and education
- controls pest population
Economic Importance for Humans: Negative
There are no known adverse affects of the eagle owl on humans.
Conservation Status
Eagle owls are considered rare but not yet threatened. Their numbers are steadily
declining due to habitat loss from human encroachment.
Additional Links
Contributors
Matthew Wund (editor), University of Michigan-Ann Arbor.
Jessie Cantrell (author), University of Michigan-Ann Arbor, Phil Myers (editor), Museum of Zoology, University of Michigan-Ann Arbor.
- Palearctic
-
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
- oriental
-
found in the oriental region of the world. In other words, India and southeast Asia.
- Ethiopian
-
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- holarctic
-
a distribution that more or less circles the Arctic, so occurring in both the Nearctic and Palearctic biogeographic regions.
Found in northern North America and northern Europe or Asia.
- cosmopolitan
-
having a worldwide distribution. Found on all continents (except maybe Antarctica) and in all biogeographic provinces; or in all the major oceans (Atlantic, Indian, and Pacific.
- 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).
- polar
-
the regions of the earth that surround the north and south poles, from the north pole to 60 degrees north and from the south pole to 60 degrees south.
- terrestrial
-
Living on the ground.
- tundra
-
A terrestrial biome with low, shrubby or mat-like vegetation found at extremely high latitudes or elevations, near the limit of plant growth. Soils usually subject to permafrost. Plant diversity is typically low and the growing season is short.
- taiga
-
Coniferous or boreal forest, located in a band across northern North America, Europe, and Asia. This terrestrial biome also occurs at high elevations. Long, cold winters and short, wet summers. Few species of trees are present; these are primarily conifers that grow in dense stands with little undergrowth. Some deciduous trees also may be present.
- 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.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- scrub forest
-
scrub forests develop in areas that experience dry seasons.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- marsh
-
marshes are wetland areas often dominated by grasses and reeds.
- swamp
-
a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.
- suburban
-
living in residential areas on the outskirts of large cities or towns.
- agricultural
-
living in landscapes dominated by human agriculture.
- 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.
- 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
- fertilization
-
union of egg and spermatozoan
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- male parental care
-
parental care is carried out by males
- female parental care
-
parental care is carried out by females
- arboreal
-
Referring to an animal that lives in trees; tree-climbing.
- nocturnal
-
active during the night
- crepuscular
-
active at dawn and dusk
- motile
-
having the capacity to move from one place to another.
- solitary
-
lives alone
- 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
- visual
-
uses sight to communicate
- acoustic
-
uses sound to communicate
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- vibrations
-
movements of a hard surface that are produced by animals as signals to others
- 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.
- keystone species
-
a species whose presence or absence strongly affects populations of other species in that area such that the extirpation of the keystone species in an area will result in the ultimate extirpation of many more species in that area (Example: sea otter).
- 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.
References
Konig, C., J. Becking, F. Weick. 1999. Owls: A Guide to the Owls of the World . New York, NY: Yale University Press.
Parry-Jones, J. 1998. Understanding Owls: Biology, Management, Breeding, Training . New York, NY: David and Charles.
Penteriani, V., M. Gallardo, P. Roche. 2002. Landscape structure and food supply affect eagle owl (Bubo bubo) density and breeding performance: a case of intra-population heterogeneity. Journal of Zoology , 257: 365-372.
Woburn Safari Park, "Woburn Safari Park" (On-line ). Amazing Animal Facts. Accessed 3/21/03 at http://www.woburnsafari.co.uk/animalfacts.asp?aID=11 .
The Peregrine Fund. 2003. "Eurasian Eagle Owl" (On-line). The Peregrine Fund. Accessed March 21, 2003 at http://www.peregrinefund.org/Explore_Raptors/owls/eagleowl.html .
Centre for the Conservation of Specialized Species. 2002. "The Eurasian Eagle Owl" (On-line ). The Centre for the Conservation of Specialized Species. Accessed 3/21/03 at http://www.conservationcentre.org/scase21.html .