Elf owl

Last updated

Contents

Elf owl
Micrathene whitneyi 29APR12 Madera Canyon AZ.jpg
CITES Appendix II (CITES) [2]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Strigiformes
Family: Strigidae
Genus: Micrathene
Coues, 1866
Species:
M. whitneyi
Binomial name
Micrathene whitneyi
(J. G. Cooper, 1861)
Micrathene whitneyi map.svg

The elf owl (Micrathene whitneyi) is a small grayish-brown owl about the size of a sparrow found in the Southwestern United States, central Mexico, and the Baja California peninsula. [3] [4] It has pale yellow eyes highlighted by thin white "eyebrows" and a gray bill with a horn-colored tip. The elf owl frequently inhabit woodpecker holes in saguaro cacti; it also nests in natural tree cavities. [5] It is nocturnal and feeds primarily on insects. [6]

Taxonomy

The elf owl was formally described in 1861 by the American naturalist James Graham Cooper from a specimen collected near Fort Mohave in Arizona. He coined the binomial name Athene whitneyi, choosing the specific epithet to honour the geologist Josiah Whitney. [7] The owl is now the only species placed in the genus Micrathene that was introduced in 1866 specifically for the elf owl by American ornithologist Elliott Coues. [8] [9] The genus name combines the Ancient Greek mikros meaning "small" and the genus name Athene that had been introduced by Friedrich Boie in 1822. [10]

A molecular phylogenetic study of the owls published in 2019 found that the elf owl is a sister species to the South American long-whiskered owlet (Xenoglaux loweryi) that was first described in 1977. [11]

Four subspecies are recognized: [9]

M. w. idonea, the subspecies in southernmost Texas to central Mexico, is resident, as are the isolated M. w. sanfordi of southernmost Baja California and M. w. graysoni (Socorro elf owl) of Socorro Island, southwest from the tip of Baja California. The Socorro elf owl has not been recorded since 1931 and is assumed to be extinct. [12]

Description

The elf owl is the world's lightest owl, although the long-whiskered owlet and the Tamaulipas pygmy owl are of a similarly diminutive length. [13] It is also the world's smallest owl. [14] The mean body weight of this species is 40 g (1.4 oz). These tiny owls are 12.5 to 14.5 cm (4.9 to 5.7 in) long and have a wingspan of about 27 cm (10.5 in). [15] Their primary projection (flight feather) extends nearly past their tail. They have fairly long legs and often appear bow-legged.

They are often found in chaparral, and are easily found during their breeding season. During dusk and just before dawn are the times this owl is most active, when they can often be heard calling to one another in a high-pitched whinny or chuckle. These songs often consist of 5–7 notes that repeat in short duration, similar to the sound of a young puppy. [16] The distinctive vocalizations of elf owls vary according to sex, with males exhibiting a wider repertoire of complex notes as opposed to females of the same species. Males have two primary classifications of songs, each of which share similar characteristics of structure and function. Most avian observers refer to "Class A" songs to describe those that vary in length (generally 5–15 notes), and are used as both territorial proclamation and to herald the arrival of males to females in the area. While Class A tones reflect changes in environmental factors — wind, precipitation, moonlight, and temperature — Class B songs have significantly less variation among individuals. Class B functions as the primary mating call, stimulating females and encouraging them to accept male sexual advances. As the season goes on and mating begins, Class A songs are observed with lower frequency than Class B. There are also a handful of locational, so-called "scolding", and territorial songs belonging to both male and female birds of the elf owl species. [17]

Distribution and habitat

The elf owl is known to migrate in large groups, with patterns of migration varying depending on flock and habitat location. Some broods of elf owl migrate to the southwest United States (California, Arizona, New Mexico, and Texas) in the spring and summer for breeding. In the winter, it is found in central and southern Mexico. Migrant elf owls return north in mid-April to early May. Resident populations occur in a couple of places in south central Mexico and along the Baja peninsula. [18]

Behaviour and ecology

Elf owls feign death when handled, an adaption that encourages a predator to relax its grip so that the owl can escape. Elf owls are also notoriously territorial. Territories are established by the male and are defended by both the male and the female, and males also tend to view their chosen female mate as a territory to be defended, as well. [17] This defense is often accomplished through the use of song. During the breeding season, elf owls are monogamous and stay in breeding pairs, but can be found in small groups during migration and when mobbing predators. Adults as well as young can be subject to predation by other predatory birds such as jays, hawks, and owls.

Breeding

Elf owls usually choose abandoned, north-facing woodpecker cavities in saguaro cacti, sycamores, cottonwoods, and other hardwood trees, to raise their young. While some cavity nesters utilize vegetation as nesting substrate, elf owls have been observed removing this vegetation and prefer a bare cavity. While elf owls primarily use natural structures for their nesting, they have been known to nest in man-made structures such as telephone poles in urban areas. As populations decrease due to encroachment by urbanization, this may serve elf owls well (for more, see Conservation status). [16]

They generally mate for periods of three months, with male and female birds remaining in close proximity. During this time, females engage in the singing of locational calls (see Description for more information on elf owl vocalizations), and males respond with mating rituals of their own. Males and female forage independently during this time, but the male elf owl will often hunt for the female as she remains in the pairs' chosen habitat for the mating season. [17]

While three eggs is a very common clutch size, females may lay anywhere from one to five eggs in springtime (late March to early May). The eggs are usually round or oval shaped with a white coloration and are from 26.8 x 23.2 to 29.9 x 25.0 mm in size. The eggs are incubated for about 24 days before the chicks hatch. [17] The young owlets fledge at about 10 weeks. Usually, chicks are born in mid-June or early July. By the end of July, they are almost always fledged and ready to set out on their own.

After the young hatch, the female elf owl watches over them in the nesting cavity while the male often hunts for the young and the female herself. The male elf owl does most of the caretaking himself, feeding his brood independent of the female, who resides in the cavity. Generally this period of communal rearing lasts until the brood is 17 to 21 days of age. [17]

Elf owls live 3 to 6 years; in captivity they may live up to 10 years. [19] The most common types of mortality for these owls are predation, exposure, and inter-species as well as intra-species competition. [20]

Food and feeding

Hunting is performed mostly during nocturnal hours. Straight line flight is often deployed for this purpose but they will use an arced flight when in the vicinity of the nest and for flying to and from perches. They live in cacti much like some birds, using the shade and climate the cacti provide.

Elf owls feed mainly on arthropods such as moths, crickets, scorpions, centipedes, and beetles. Agaves and ocotillos are ideal places for foraging, as moths and other insects may be found in their flowers. In urban areas they can be seen utilizing outdoor lights that attract bugs as areas for insect hunting. They are often seen chasing after flying insects, with a flight similar to a tyrant flycatcher's. They also feed on scorpions. Once the owl has killed the scorpion, they can be observed removing the stinger before consumption. The elf owls seem to not be bothered by scorpion stings. They will also feed on small mammals (such as kangaroo rats), reptiles (spiny lizards, earless lizards and blind snakes) and birds, on occasion. [17] [21]

Conservation status

Populations of elf owls have continued to decline in recent years due to a continued loss of native habitats, particularly those in the desert areas of California. [22] Human activities, like increasing water diversion and home construction, have decimated these desert and riparian areas, as well as increasingly abundant invasive species (such as the salt cedar). The destruction of habitat leaves many elf owls unable to nest, hunt, and reproduce in areas like California, Arizona, and elsewhere. [22]

To date, elf owls are not considered a globally threatened species, yet they are listed as "endangered" in California due to a population of fewer than 150,000 individual owls in the United States. California has implemented a captive breeding program in an attempt to increase this number, while numerous environmental and government agencies work to preserve their riparian and desert homes. [16] Some sources report that the elf owl has already been nearly eliminated in California. [23]

In fiction

An elf owl named Gylfie is a major character in the Guardians of Ga'Hoole book series by Kathryn Lasky, and the 2010 film adaptation.

Related Research Articles

<span class="mw-page-title-main">Northern cardinal</span> Species of North American bird

The northern cardinal, known colloquially as the redbird, common cardinal, red cardinal, or just cardinal, is a bird in the genus Cardinalis. It can be found in southeastern Canada, through the eastern United States from Maine to Minnesota to Texas, New Mexico, southern Arizona, southern California, and south through Mexico, Belize, and Guatemala. It is also an introduced species in a few locations such as Bermuda and Hawaii. Its habitat includes woodlands, gardens, shrublands, and wetlands. It is the state bird of Illinois, Indiana, Kentucky, North Carolina, Ohio, Virginia, and West Virginia.

<span class="mw-page-title-main">Western bluebird</span> Species of bird

The western bluebird is a small North American thrush.

<span class="mw-page-title-main">Acorn woodpecker</span> Species of bird

The acorn woodpecker is a medium-sized woodpecker with a length of around 20 cm (8 in), and an average weight of 85 g (3.0 oz). It is found across Central America, as well as the western United States and parts of Colombia.

<span class="mw-page-title-main">Great horned owl</span> Species of owl

The great horned owl, also known as the tiger owl or the hoot owl, is a large owl native to the Americas. It is an extremely adaptable bird with a vast range and is the most widely distributed true owl in the Americas. Its primary diet is rabbits and hares, rats and mice, and voles, although it freely hunts any animal it can overtake, including rodents and other small mammals, larger mid-sized mammals, birds, reptiles, amphibians, and invertebrates.

<span class="mw-page-title-main">Western screech owl</span> Species of owl

The western screech owl is a small owl native to North and Central America, closely related to the eastern screech owl. The scientific name commemorates the American naturalist Robert Kennicott.

<span class="mw-page-title-main">Revillagigedo Islands</span> Group of four volcanic islands in the Pacific Ocean

The Revillagigedo Islands or Revillagigedo Archipelago are a group of four volcanic islands in the Pacific Ocean, known for their unique ecosystem. They lie approximately 458 kilometres (285 mi) from Socorro Island south and southwest of Cabo San Lucas, the southern tip of the Baja California Peninsula, and 698 to 1,092 kilometres west of Manzanillo. Historically linked to the Mexican state of Colima, to which they were granted in 1861 to establish a penal colony, the islands are under Mexican federal property and jurisdiction.

<span class="mw-page-title-main">Spotted owlet</span> Species of owl

The spotted owlet is a small owl which breeds in tropical Asia from mainland India to Southeast Asia. A common resident of open habitats including farmland and human habitation, it has adapted to living in cities. They roost in small groups in the hollows of trees or in cavities in rocks and buildings. It nests in a hole in a tree or building, laying 3–5 eggs. The species shows great variation including clinal variation in size and forms a superspecies with the very similar little owl.

<span class="mw-page-title-main">Harris's hawk</span> Species of bird

Harris's hawk, formerly known as the bay-winged hawk, dusky hawk, and sometimes a wolf hawk, and known in Latin America as peuco, is a medium-large bird of prey that breeds from the southwestern United States south to Chile, central Argentina, and Brazil. This bird is sometimes reported to be at large in Western Europe, especially Britain, but it is a popular species in falconry and these records almost invariably all refer to escapes from captivity.

<span class="mw-page-title-main">Flammulated owl</span> Species of owl

The flammulated owl is a small migratory North American owl in the family Strigidae. It is the only species placed in the genus Psiloscops.

<span class="mw-page-title-main">Socorro mockingbird</span> Species of bird

The Socorro mockingbird is an endangered mockingbird endemic to Socorro Island in Mexico's Revillagigedo Islands. The specific epithet commemorates the American ornithologist Andrew Jackson Grayson.

<span class="mw-page-title-main">Ferruginous pygmy owl</span> Species of owl

The ferruginous pygmy owl is a small owl that breeds in south-central Arizona and southern Texas in the United States, south through Mexico and Central America, to South America into Brazil, Bolivia, Paraguay and Argentina.

<span class="mw-page-title-main">Gila woodpecker</span> Species of bird

The Gila woodpecker is a medium-sized woodpecker of the desert regions of the southwestern United States and western Mexico. In the U.S., they range through southeastern California, southern Nevada, Arizona, and New Mexico.

<span class="mw-page-title-main">Bewick's wren</span> Species of bird

The Bewick's wren is a wren native to North America. It is the only species placed in the genus Thryomanes. At about 14 cm (5.5 in) long, it is grey-brown above, white below, with a long white eyebrow. While similar in appearance to the Carolina wren, it has a long tail that is tipped in white. The song is loud and melodious, much like the song of other wrens. It lives in thickets, brush piles and hedgerows, open woodlands and scrubby areas, often near streams. It eats insects and spiders, which it gleans from vegetation or finds on the ground.

<span class="mw-page-title-main">Pyrrhuloxia</span> Species of bird

The pyrrhuloxia or desert cardinal is a medium-sized North American songbird found in the American southwest and northern Mexico. This distinctive species with a short, stout bill and red crest and wings, and closely resembles the northern cardinal and the vermilion cardinal, which are in the same genus.

<span class="mw-page-title-main">Aridoamerica</span> Ecological region of North America

Aridoamerica denotes an ecological region spanning Northern Mexico and the Southwestern United States, defined by the presence of the culturally significant staple foodstuff Phaseolus acutifolius, a drought-resistant bean. Its dry, arid climate and geography stand in contrast to the verdant Mesoamerica of present-day central Mexico into Central America to the south and east, and the higher, milder "island" of Oasisamerica to the north. Aridoamerica overlaps with both.

<span class="mw-page-title-main">Common poorwill</span> Species of bird

The common poorwill is a nocturnal bird of the family Caprimulgidae, the nightjars. It is found from British Columbia and southeastern Alberta, through the western United States to northern Mexico. The bird's habitat is dry, open areas with grasses or shrubs, and even stony desert slopes with very little vegetation.

<span class="mw-page-title-main">Northern pygmy owl</span> Species of owl

The northern pygmy owl is a small owl native to western North America.

<span class="mw-page-title-main">Broad-billed hummingbird</span> North-American hummingbird

The broad-billed hummingbird is a small-sized hummingbird that resides in Mexico and the southwestern United States. The bird displays sexual dimorphism, and the juveniles resemble the female adult more than the male adult. The broad-billed hummingbird is a bright coloured bird with a broad and bright red bill. The bird is also known for its other common names – the Colibrí Pico Ancho in Spanish and Colibri circé in French. It is a diurnal bird.

<span class="mw-page-title-main">Cactus wren</span> Species of bird found in North America

The cactus wren is a species of wren that is endemic to the deserts of the southwestern United States and northern and central Mexico. It is the state bird of Arizona, and the largest wren in the United States. Its plumage is brown, with black and white spots as markings. It has a distinctive white eyebrow that sweeps to the nape of the neck. The chest is white, whereas the underparts are cinnamon-buff colored. Both sexes appear similar. The tail, as well as flight feathers, are barred in black and white. Their song is a loud raspy chirrup; akin in the description of some ornithologists to the sound of a car engine that will not start. It is well-adapted to its native desert environment, and the birds can meet their water needs from their diet which consists chiefly of insects, but also of some plant matter. The cactus wren is a poor flier and generally forages for food on the ground. Ornithologists generally recognize seven subspecies, with the exact taxonomy under dispute.

<span class="mw-page-title-main">Mountain pygmy owl</span> Species of owl

The mountain pygmy owl is a small species of owl from the family Strigidae. They reside throughout southern Arizona, New Mexico and Mexico.

References

  1. BirdLife International (2016). "Micrathene whitneyi". IUCN Red List of Threatened Species . 2016: e.T22689325A93226849. doi: 10.2305/IUCN.UK.2016-3.RLTS.T22689325A93226849.en . Retrieved 13 November 2021.
  2. "Appendices | CITES". cites.org. Retrieved 2022-01-14.
  3. Peterson, Roger Tory, 1908-1996. (1990). A Field Guide to Western Birds. Peterson, Virginia Marie, 1925-, National Audubon Society., National Wildlife Federation., Roger Tory Peterson Institute. (Third edition, completely revised and enlarged ed.). Boston: Houghton Mifflin Company. p. 204. ISBN   0-395-51424-X. OCLC   19511450.{{cite book}}: CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link)
  4. "Elf Owl - Distribution Neotropical Birds Online". neotropical.birds.cornell.edu. doi:10.2173/bow.elfowl.01 . Retrieved 2020-02-07.
  5. "Elf Owl Fact Sheet". www.desertmuseum.org. Retrieved 2020-02-07.
  6. "Elf Owl - Introduction Neotropical Birds Online". neotropical.birds.cornell.edu. doi:10.2173/bow.elfowl.01 . Retrieved 2020-02-07.
  7. Cooper, James Graham (1861). "New Californian animals". Proceedings of the California Academy of Natural Sciences. 1st. 2: 118–123 [118–119].
  8. Coues, Elliott (1866). "List of the birds of Fort Whipple, Arizona: with which are incorporated all other species ascertained to inhabit the territory ; with brief critical and field notes, descriptions of new species, etc". Proceedings of the Academy of Natural Sciences of Philadelphia. 18: 39–100 [51].
  9. 1 2 Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (January 2021). "Owls". IOC World Bird List Version 11.1. International Ornithologists' Union. Retrieved 22 May 2021.
  10. Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. p. 253. ISBN   978-1-4081-2501-4.
  11. Salter, J.F.; Oliveros, C.H.; Hosner, P.A.; Manthey, J.D.; Robbins, M.B.; Moyle, R.G.; Brumfield, R.T.; Faircloth, B.C. (2019). "Extensive paraphyly in the typical owl family (Strigidae)". The Auk. 137 (ukz070). doi: 10.1093/auk/ukz070 . hdl: 2346/93048 .
  12. Wehtje, W.; Walter, H.S.; Estrella, R.R.; Llinas, J.; Vera, A.C. (1993). "An annotated checklist of the birds of Isla Socorro, Mexico" (PDF). Western Birds. 24 (1): 1–16.
  13. "Elf Owl – Micrathene whitneyi". Owling.com. Retrieved 30 March 2013.
  14. Sciences, written by Edward Stanley Brinkley ; foreword by Craig Tufts ; photographs supplied by VIREO, the Academy of Natural (2008). Field guide to birds of North America. New York [u.a.]: Sterling. ISBN   978-1-4027-3874-6.{{cite book}}: CS1 maint: multiple names: authors list (link)
  15. Owls: A Guide to the Owls of the World by Claus Konig, Friedhelm Welck & Jan-Hendrik Becking. Yale University Press (1999), ISBN   978-0-300-07920-3.
  16. 1 2 3 "Elf Owl". American Bird Conservancy. Retrieved 2020-11-02.
  17. 1 2 3 4 5 6 Ligon, J. David (February 27, 1968). "The Biology of the Elf Owl, Micrathene whitneyi". Miscellaneous Publications Museum of Zoology, University of Michigan Press. 136: 76 via JSTO.
  18. Backhouse, Frances (2013). Owls of North America. Buffalo, N.Y.: Firefly Books. ISBN   978-1770852327.
  19. "Elf Owl Fact Sheet". Arizona-Sonora Desert Museum. Retrieved 30 March 2013.
  20. "Micrathene whitneyi (elf owl)". Animal Diversity Web.
  21. "Micrathene whitneyi (Elf owl)". Animal Diversity Web .
  22. 1 2 "Elf Owl I Owl Research Institute". owlresearchinstitute. Retrieved 2020-11-02.
  23. Lehman, Paul (2011). National Geographic Field Guide to the Birds of North America (6th ed.). National Geographic Society.

General references