At hatching (Van Nieuwenhuyse, et al., 2008)has pink skin, cere, and toes and a light white or gray bill and claws. The first down is called neoptile and is short and white. After one week the second down, the mesoptile, begins to grow and young little owls appear a mottled gray color. The mesoptile resembles feathers but is shorter and softer. On the tenth day, the eyes open and the iris is a light yellow color. For three or four weeks the neoptile is still attached to the mesoptile. Overall the young little owls are grayer and show less contrast in their coloring than adults. Even first year adults have differences in feather shape and texture than older adults.
Little owl adults are mostly a dark brown color with cream markings over the entire body. The cream markings include streaks on the forehead and crown, rings around the eyes, a cream chin, spots and streaks on the breast and abdomen, round spots on the back and tail, and a distinct V-shape mark on the back of the head. The males and females share a similar appearance with males tending to have a lighter face. The bill and iris of (Van Nieuwenhuyse, et al., 2008)are bright yellow and the eyelids are dark. The cere, a part of the bill, is grayish to black in color. The legs are gray with a possible yellow tint. The toes are a darker gray to brown or black color and the claws are dark brown to black. Some coloring anomalies have been reported including partial albinism, leucistic coloration, or a russet color.
The wing length of (Van Nieuwenhuyse, et al., 2008)has a reported maximum of 174 mm and minimum of 158 mm but normally ranges between 151 mm and 178 mm. The wingspan of male little owls is 557.67 mm (plus or minus 11.90 mm) and for females the wingspan was recorded as 565.64 mm (plus or minus 13.15 mm). Females are generally larger than males and on average have a wing length that is 3 to 5 mm longer than males. Also, one year old little owls have a wing length that is, on average, 3 mm shorter than older adults. The subspecies of do differ in sizes with the largest little owls from Tibet and Kashmir mountains and the smallest little owls from northeast Africa.
As the common name suggests, little owls are small with an average weight of 164 g. Male little owls are 9 to 10% lighter than females. The minimum recorded weight of an (Johnson, et al., 2009; MØLLER, 2006; Van Nieuwenhuyse, et al., 2008)is 98 g, the wild maximum is 270 to 280 g, and the maximum recorded in captivity is 300 to 350 g.
is iteroparous (produces a clutch every year). The mating season of begins in early February and ends as late as May depending on the region. The time of egg-laying also varies with the location but can begin as early as March and end as late as August when taking into account replacement clutches. The clutch size is normally between 1 and 7, averaging 3.3, but as many as 12 has been recorded. If the first clutch is lost for some reason, a pair can lay a replacement clutch, usually of a smaller size. As soon as the eggs are laid, the incubation period begins. The incubation period is from 18 to 35 days, usually reported as 28 days. Overall hatching occurs approximately one month after laying and owlets are dependent upon the parents for two months. The average weight of newly hatched owlets is 10 to 12 g. The female remains with the nestlings for 16 days. The owlets begin to catch their own prey at 28 days and kill prey at 34 days. The offspring become fledglings as early as 28 days and as late as 35 days. The owlets become juveniles and no longer need parental care between August and the beginning of November. The juveniles settle an average of 2700 m away from their first nest. The little owls reach reproductive age at 1 year.
Hatching success of little owls is as low as 49.3%. Fledging success has been reported as low as 46.6%. These losses can be due to infertility, adults losing or abandoning the nest, predation, low prey availability, and other nest complications. The most important trait linked to the production of young is food availability. The success of young is effected by the distance of the nest to the hunting grounds and by weather during the preceding winter, the breeding season, and after hatching. Supplementing nests with food has been shown to greatly increase the production of young. The number of young fledged per breeding pair ranges from 0.6 to 2.8 fledglings per pair. (Grzywaczewski, 2009; Holsegård-Rasmussen, et al., 2009; Johnson, et al., 2009; Le Gouar, et al., 2010; MØLLER, 2006; Thorup, et al., 2010; Tomé, et al., 2008; Van Nieuwenhuyse, et al., 2008)
Before copulation occurs, little owls must strengthen pair bonding. Part of this pair bonding includes the male defending his territory and providing food to the female. The female must develop fat reserves to help her produce eggs before the nest site is selected. Before the female lays eggs, she remains in the nest and the male brings prey to her. As soon as the eggs have been laid, the female begins incubating the eggs to keep them warm. Pre-hatching parental investment also includes the male bringing the female food as she incubates the eggs. The eggs hatch after about 28 days and the pre-fledging parental care begins. The male still catches prey and brings it back to the nest for the nestlings and female. The female defends, warms, and feeds her young. After 16 days the female also leaves the nest and begins bringing prey back for the nestlings. The offspring become fledglings as early as 28 days and as late as 35 days. Pre-independence parental care includes the parents still feeding and protecting the owlets one month after they reach fledgling age. Parental care ceases at the beginning of September to the beginning of November. In general, there is a two month post-hatching dependency period in which the parents are very active and energetically stressed. As the brood ages, the activity rates of the parents increase. The males are more active than the females during this period and are the main food provider, possibly linked to their lighter weight allowing them to move further and faster. Also the heavier weight of the females may help them care for and defend the nest. Although the roles of the (Holsegård-Rasmussen, et al., 2009; Thorup, et al., 2010; Van Nieuwenhuyse, et al., 2008)parents are different, both provide provisioning and protection throughout the development of the young.
The home ranges of little owls vary in size throughout the year from 1.8 to 95.0 ha (.018 to .95 km^2). The average home range is 15.1 ha (.151 km^2). Through the winter little owls must scavenge for scarce food. This contributes to the larger sizes of home ranges and increases overlaps of territories among individuals. Home ranges decrease and do not overlap during the breeding season. The decrease in home range is influenced by an increase in energy expenditure during courtship, laying, hatching, and raising of owlets. Little owls require more energy to defend and hunt a larger territory. Also, the parents must hunt closer to the nest to reduce the amount of energy spent on travel. The smallest home ranges were seen during the laying period, with an increase during incubation and nestling periods. There is another decrease in home range during the fledgling period of offspring. The second smallest home ranges were observed as juveniles reached independence. It is believed parents decrease and defend their home range to scare independent juveniles out of their natal territory. Owls that have lost clutches or were unsuccessful in breeding will increase their home ranges and often forage in the same areas as other owls. Although, (Grzywaczewski, 2009; Van Nieuwenhuyse, et al., 2008; Zuberogoitia, et al., 2007)is territorial, there has been little or no aggression found between little owls near each other. The average distance between little owl nests is 560 m.
is a very vocal bird with a repertoire of between 22 and 40 different calls. These calls are are used to contact or attract mates, defend territories against enemies and other little owls, alarm, and communicate. The vocalizations occur on average 1.87 times per hour and there is an average of 415 total seconds of calling in an hour. The vocal activity varies with time of year and day. There is usually a peak in calling before and during courtship and is lowest in the winter and summer. Also, there is an increase in call duration at dusk, called a dusk chorus phenomenon and a less pronounced increase at dawn with a lull through the night. There are more song vocalizations than calls at night. Also, little owls have been known to vocalize during daylight. The female call is generally shorter and higher pitched than the male call. The male calls are also louder and clearer than the female calls. When a predator is detected, quiets and waits until the threat is presumably gone before resuming vocal activity. It has also been demonstrated that little owls learn to recognize the calls of neighboring little owls versus unknown little owls to reduce energy expenditure during territory defense.
Sight and hearing also allow little owls to perceive their environment. Little owls have retinal cells more similar to diurnal birds and have the poorest visual acuity compared to other birds of prey. (Hardouin, et al., 2008; Johnson, et al., 2009; Van Nieuwenhuyse, et al., 2008; Zuberogoitia, et al., 2007; Zuberogoitia, et al., 2008)can see yellow, green, blue, and (to a lesser extent) red. Little owls can also distinguish between different shades of gray, increasing the ability to see at night. Little owls can also hear sound frequencies of 3 to 4 kilocycles per second (kc/s). This ability to hear allows to locate rodents extremely accurately. Little owl pairs often preen and scratch each other and sleep in contact with each other. These tactile cues are used to increase pair bonding between mates. Mutual preening has also been seen amongst fledgling siblings.
Little owls hunt in various ways, even mixing the styles of hunting to suit their prey. They can be found perching and watching the ground or the air. To catch prey items on the ground, mammals, birds, reptiles, amphibians, fish, insects, molluscs, crustaceans, and other invertebrate species. The diet mainly consists of small rodents and large invertebrates (earthworms and insects). In the palearctic region, is recorded to prey on 544 different species. The portions of the prey that little owls cannot digest are compacted internally and regurgitated as a pellet. (Hardouin, et al., 2008; Holsegård-Rasmussen, et al., 2009; Johnson, et al., 2009; Le Gouar, et al., 2010; Thorup, et al., 2010; Tomé, et al., 2008; Van Nieuwenhuyse, et al., 2008; Zuberogoitia, et al., 2008)will run and hop along the ground. They can also catch prey on the ground while flying low. can catch prey out of the air while flying as well. carries its prey with either its beak or claws. Males and females hunt and carry prey similarly, but females seem to prefer to carry prey by the neck, whereas males carry prey more often by the head. Little owls are known to catch prey as heavy as themselves. Little owls also create holes to hold surplus food. Hunting occurs mostly at night or dusk, but they have been seen hunting in daytime. is an opportunistic carnivore that is known to feed on a wide variety of prey including
Little owls have many anti-predator adaptations. Tyto alba), little owls will hide or become silent until the threat is perceived to be gone. Although not a normal predator of , sometimes intraguild predation occurs between little owls and Tyto alba. The predators of little owls are larger birds including tawny owls, eagle owls, long-eared owls, peregrine falcons, common buzzards, goshawks, sparrowhawks, red kites, tawny eagles, rough-legged buzzards, booted eagles, lanners, marsh harriers, black kites, imperial eagles, and long-legged buzzards. Other predators include pine martens, feral cats, fox, domestic dogs, and corvids. The main predators of the nests are mammals, including stone martens and common genets. The eggs and chicks of little owls are predated upon by stoats, hedgehogs, brown rats, corvids, and magpies. (Hardouin, et al., 2008; Tomé, et al., 2008; Van Nieuwenhuyse, et al., 2008; Zuberogoitia, et al., 2008; Żmihorski, et al., 2009)is known to call in response to predators as an alarm and defense. When other little owls hear the defense call they will hide. When sleeps, the white markings are hidden which allows the owl to camouflage. Also, the V-shaped marking on the back of the head mimics eyes to prevent predation from behind. Further, it has been noted that in the presence of barn owls (
Little owls feed mainly on insects and small mammals and can keep these populations under control. Also, Trichophagata petzella and Monopis laevigell. There are at least 67 parasite species of little owls. The main types of parasites are from the groups Protozoa, Sporozoa, Metazoa, Nemathelminthes, Arachnida, and Insecta. The blood parasite Leucocytozoon ziemanni and the ectoparasite dipteran Carnus hemapterus have been reported to use little owls as hosts. It could be stated that is a commensal species of humans. The little owls use agricultural landscapes and urban and suburban areas as habitats. Also, little owls have been seen following farming equipment that stirs up insects and taking "smoke" baths in the rising smoke of chimneys. (Van Nieuwenhuyse, et al., 2008)serves as the prey for other species. Although interacts with many species, there are no mutualistic relationships documented. Two commensal species of little owls are
Little owls eat many insects and small mammals, controlling populations that are pests to humans. There has been a dramatic decline in some owl populations throughout Europe, including (Van Nieuwenhuyse, et al., 2008). is perfect for studying owl declines in rural habitats because the species is well known to the public, present in significant numbers, easy to research, and quickly reacts to conservation actions. The presence of attracts predators that were once desirable to humans. Due to this, little owls used to be traded and carried on staffs to attract and catch their predators. Little owls were also once traded as pets.
Little owls have been associated with humanity for centuries. Athene. Little owls can still be found in modern art today. Currently there are 12 recognized subspecies of : A. n. noctua, A. n. vidalii, A. n. indigena, A. n. glaux, A. n. saharae, A. n. lilith, A. n. bactriana, A. n. ludlowi, A. n. orientalis, A. n. plumipes, A. n. impasta, and A. n. spilogastra. (Van Nieuwenhuyse, et al., 2008)is seen as an omen of death, a sign of wisdom, and even a symbol of creators across time and civilizations. Little owls can be found on coins, medallions, in literature, and other works of art dating as far back as 8000 to 7500 BCE. The little owls were traded to hunt small birds and even used as domesticated pets. was the bird of Athena, the Greek Goddess of Wisdom, and the origin of the genus name
Kevin Hunt (author), Indiana University-Purdue University Fort Wayne, Mark Jordan (editor), Indiana University-Purdue University Fort Wayne, Rachelle Sterling (editor), Special Projects.
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
uses sound to communicate
living in landscapes dominated by human agriculture.
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.
Referring to an animal that lives in trees; tree-climbing.
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.
an animal that mainly eats meat
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.
uses smells or other chemicals to communicate
to jointly display, usually with sounds, at the same time as two or more other individuals of the same or different species
active at dawn and dusk
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.
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.
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.
parental care is carried out by females
union of egg and spermatozoan
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).
parental care is carried out by males
Having one mate at a time.
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
the area in which the animal is naturally found, the region in which it is endemic.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
places a food item in a special place to be eaten later. Also called "hoarding"
living in residential areas on the outskirts of large cities or towns.
uses touch to communicate
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).
Living on the ground.
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
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.
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.
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.
living in cities and large towns, landscapes dominated by human structures and activity.
uses sight to communicate
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Zuberogoitia, I., J. Zabala, J. Martínez, S. Hidalgo, J. Martínez, A. Azkona, I. Castillo. 2007. Seasonal dynamics in social behaviour and spacing patterns of the little owl Athene noctua. Ornis Fennica, 84: 173-180.
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