Boreal owl: Difference between revisions
Content deleted Content added
rm defsort |
m Open access bot: hdl, doi updated in citation with #oabot. |
||
| (25 intermediate revisions by 16 users not shown) | |||
| Line 7: | Line 7: | ||
| status = LC |
| status = LC |
||
| status_system = IUCN3.1 |
| status_system = IUCN3.1 |
||
| status_ref = <ref name="iucn status 12 November 2021">{{cite iucn |author=BirdLife International |date= |
| status_ref = <ref name="iucn status 12 November 2021">{{cite iucn |author=BirdLife International |date=2021 |title=''Aegolius funereus'' |volume=2021 |page=e.T22689362A201898946 |doi=10.2305/IUCN.UK.2021-3.RLTS.T22689362A201898946.en |access-date=12 November 2021}}</ref> |
||
| status2 = CITES_A2 |
| status2 = CITES_A2 |
||
| status2_system = CITES |
| status2_system = CITES |
||
| Line 23: | Line 23: | ||
*''Strix tengmalmi'' {{small|Gmelin, 1788}} |
*''Strix tengmalmi'' {{small|Gmelin, 1788}} |
||
| synonyms_ref = <ref name=avibase>{{avibase|8AB4EAF6DBFA02CE|Aegolius funereus}}</ref> |
| synonyms_ref = <ref name=avibase>{{avibase|8AB4EAF6DBFA02CE|Aegolius funereus}}</ref> |
||
| range_map = |
| range_map = AegoliusFunereusIUCN.svg |
||
| range_map_caption = Range of ''A. funereus'' |
| range_map_caption = Range of ''A. funereus'' |
||
{{leftlegend|#008000|Resident|outline=gray}}{{leftlegend|#007FFF|Non-breeding|outline=gray}} |
{{leftlegend|#008000|Resident|outline=gray}}{{leftlegend|#007FFF|Non-breeding|outline=gray}} |
||
}} |
}} |
||
The '''boreal owl''' |
The '''boreal owl''' ('''''Aegolius funereus''''') or '''Tengmalm's owl''' is a small [[owl]] in the "true owl" family [[Strigidae]]. It is known as the boreal owl in North America and as Tengmalm's owl in [[Europe]] after Swedish naturalist [[Peter Gustaf Tengmalm]] or, more rarely, Richardson's owl after [[John Richardson (naturalist)|Sir John Richardson]].<ref name=avibase/><ref>{{cite book|last=Beolens|first=Bo|title=Whose bird?: Men and women commemorated in the common names of birds.|year=2003|publisher=Helm |location=London|isbn=0713666471|author2=Watkins, Michael}}</ref> |
||
Due to the boreal owl's shyness and evasive reaction to human activities, [[Nocturnality|nocturnal habits]] and preferred inaccessible [[taiga]] forest habitat, it is rarely seen by humans. |
Due to the boreal owl's shyness and evasive reaction to human activities, [[Nocturnality|nocturnal habits]] and preferred inaccessible [[taiga]] forest habitat, it is rarely seen by humans. |
||
==Taxonomy== |
==Taxonomy== |
||
The boreal owl was [[Species description|formally described]] by the Swedish naturalist [[Carl Linnaeus]] in 1758 in the [[10th edition of Systema Naturae|tenth edition]] of his ''[[Systema Naturae]]''. Linnaeus placed it with all the other owls in the [[genus]] ''[[Strix (bird)|Strix]]'' |
The boreal owl was [[Species description|formally described]] by the Swedish naturalist [[Carl Linnaeus]] in 1758 in the [[10th edition of Systema Naturae|tenth edition]] of his ''[[Systema Naturae]]''. Linnaeus placed it with all the other owls in the [[genus]] ''[[Strix (bird)|Strix]]''and coined the [[binomial name]] ''Strix funerea''.<ref>{{cite book | last=Linnaeus | first=Carl | author-link=Carl Linnaeus | year=1758 | title= Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis | volume=1 | edition=10th | page=93 | publisher=Laurentii Salvii | location=Holmiae (Stockholm) | language=Latin | url=https://www.biodiversitylibrary.org/page/764491}}</ref> The Eurasian scops owl is now placed in the genus ''[[Aegolius]]'' that was introduced in 1829 by the German naturalist [[Johann Jakob Kaup]] with the boreal owl as the [[type species]].<ref>{{ cite book | last=Kaup | first=Johann Jakob | author-link=Johann Jakob Kaup | year=1829 | title=Skizzirte Entwickelungs-Geschichte und natürliches System der europäischen Thierwelt | volume=c. 1 | language=German | place=Darmstadt | publisher=Carl Wilhelm Leske | page=34 | url=https://www.biodiversitylibrary.org/page/41576419 }}</ref><ref name=ioc>{{cite web| editor1-last=Gill | editor1-first=Frank | editor1-link=Frank Gill (ornithologist) | editor2-last=Donsker | editor2-first=David | editor3-last=Rasmussen | editor3-first=Pamela | editor3-link=Pamela Rasmussen | date=January 2022 | title=Owls | work=IOC World Bird List Version 12.1 | url=https://www.worldbirdnames.org/bow/owls/ | publisher=International Ornithologists' Union | accessdate=2 March 2022 }}</ref> The genus name is [[Latin]] for a [[screech owl]], the word came from the [[Ancient Greek]] ''aigōlios'' meaning "a bird of ill omen". The specific epithet ''funereus'' is Latin meaning "funereal".<ref>{{cite book | last=Jobling | first=James A. | year=2010| title=The Helm Dictionary of Scientific Bird Names | publisher=Christopher Helm | location=London | isbn=978-1-4081-2501-4 | pages=[https://archive.org/stream/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling#page/n33/mode/1up 33], [https://archive.org/stream/Helm_Dictionary_of_Scientific_Bird_Names_by_James_A._Jobling#page/n166/mode/1up 166]}}</ref> |
||
=== Related species === |
|||
| ⚫ | |||
Congeners include [[northern saw-whet owl]] (''A. acadicus''), [[unspotted saw-whet owl]] (''A. ridgwayi''), and [[buff-fronted owl]] (''A. harrisii''), all found in the [[New World]].<ref name=":0">{{Citation |last1=Hayward |first1=G. D. |title=Boreal Owl (Aegolius funereus) |date=2020-03-04 |work=Birds of the World |url=http://dx.doi.org/10.2173/bow.borowl.01 |access-date=2024-10-14 |publisher=Cornell Lab of Ornithology |last2=Hayward |first2=P. H.|editor-first1=Shawn M. |editor-last1=Billerman |doi=10.2173/bow.borowl.01 }}</ref> |
|||
=== Subspecies === |
|||
| ⚫ | |||
*''A.f. richardsoni'' ([[Charles Lucien Bonaparte|Bonaparte]], 1838) – [[Alaska]], north Canada and north United States |
*''A.f. richardsoni'' ([[Charles Lucien Bonaparte|Bonaparte]], 1838) – [[Alaska]], north Canada and north United States |
||
*''A.f funereus'' ([[Carl Linnaeus|Linnaeus]], 1758) – [[nominate subspecies]], from [[Scandinavia]] down south to the [[Pyrenees]] and east to the [[Urals]], but not the [[Caucasus Mountains]] |
*''A.f funereus'' ([[Carl Linnaeus|Linnaeus]], 1758) – [[nominate subspecies]], from [[Scandinavia]] down south to the [[Pyrenees]] and east to the [[Urals]], but not the [[Caucasus Mountains]] |
||
| Line 43: | Line 47: | ||
*''A.f. caucasicus'' (Buturlin, 1907) – [[Caucasus Mountains]] |
*''A.f. caucasicus'' (Buturlin, 1907) – [[Caucasus Mountains]] |
||
*''A.f. beickianus'' [[Erwin Stresemann|Stresemann]], 1928 – northwest India to southwest China |
*''A.f. beickianus'' [[Erwin Stresemann|Stresemann]], 1928 – northwest India to southwest China |
||
=== Fossil History === |
|||
Remains of the boreal owl dating back to the [[Pleistocene|Pleistocene era]] were found in a cave in southern New Mexico.<ref>{{Cite web |title=Google Scholar |url=https://scholar.google.com/scholar?hl=en&as_sdt=0,5&q=Howard,+H.+(1931d).%C2%A0Cryptoglaux+funerea%C2%A0in+New+Mexico.+Condor+33:216&btnG= |access-date=2024-10-14 |website=scholar.google.com}}</ref> Bones were found in a pueblo in north-central New Mexico that has been inhabited from around A.D. 1250 to the present.<ref>{{Cite journal |last=Emslie |first=Steven D. |date=1981-09-01 |title=Birds and prehistoric agriculture: The New Mexican pueblos |url=https://link.springer.com/article/10.1007/BF00890740 |journal=Human Ecology |language=en |volume=9 |issue=3 |pages=305–329 |doi=10.1007/BF00890740 |bibcode=1981HumEc...9..305E |issn=1572-9915}}</ref> |
|||
==Description== |
==Description== |
||
The boreal owl is small with a large head and long wings. Both sexes are similar in appearance, though females are larger. Males typically measure 21–25 cm (8.3-9.8 in) in length, with a wingspan of 55–58 cm (21.7-22.8 in), while females are larger – 25–28 cm (9.8–11 in) – with a wingspan of 59–62 cm (23.2-24.4 in). A female is heavier than a male bird and weighs 132-215 g (4.7-7.6 oz) compared to 93-139 g (3.3-4.9 oz) for a male bird. |
|||
| ⚫ | |||
The boreal owl is {{cvt|22|–|27|cm}} in length and has a wingspan of {{cvt|50|–|62|cm}}.<ref name=svensson>{{ cite book | last=Svensson | first1=Lars | last2=Mullarney | first2=Killian | last3=Zetterström | first3=Dan | year=2009 | title=Collins Bird Guide | edition=2nd | location=London | publisher=HarperCollins | isbn=978-0-00-726814-6 | page=226 }}</ref> A female is heavier than a male bird and weighs {{cvt|131|-|179|g}} compared with an average of {{cvt|107|g}} for a male bird.{{sfn|Cramp|1985|p=615}} The plumage is brown above, with white flecking on the shoulders and whitish underparts with rust-colored streaks. The head is large with yellow eyes and a dull white [[facial disc]] that is sometimes described as giving the owl a "surprised" expression. The beak is a light yellow, rather than dark like its relative the [[northern saw-whet owl]].<ref>{{cite book|title= National Audubon Society Field Guide to North American Birds: Eastern Region |last= Bull |first= Farrand |year= 1994 |publisher= Alfred A. Knopf |location= New York |isbn= 0-679-42852-6 |page= 554}}</ref> The sexes are similar in appearance. The plumage of young birds is chocolate brown. The boreal owl's flight is relatively noiseless and straight.<ref name=svensson/> |
|||
=== Adult identification === |
|||
| ⚫ | |||
The plumage is brown above, with white flecking on the shoulders and whitish underparts with rust-colored streaks. Its large head has yellow eyes and an olive-brown crown with small white droplets and larger central spots. The dull white [[facial disc]] is framed with a dark border and white “eyebrows” often described as giving the owl a "surprised" expression. The underparts are cream-white with russet-brown streaks, while the tail has olive-brown feathers with narrow bars. [[Flight feather]]s are dark olive-brown with contrasting white spots. The [[Primaries (birds)|primaries]] typically have up to five rows of white spots, while the tail has three distinct rows of spots.<ref name=":0" /> Unlike other owl species, these spots remain separated even when the tail is folded closely together.<ref name=":1">{{Cite book |url=https://ixtheo.de/Record/1081758635 |title=Handbook of the birds of Europe the Middle East and North Africa: the birds of the Western Palearctic |date=1977 |publisher=Oxford University Press |location=Oxford [u.a.]}}</ref> The beak is light yellow, rather than dark like its relative the [[northern saw-whet owl]].<ref>{{cite book|title= National Audubon Society Field Guide to North American Birds: Eastern Region |last= Bull |first= Farrand |year= 1994 |publisher= Alfred A. Knopf |location= New York |isbn= 0-679-42852-6 |page= 554}}</ref> The ears are asymmetrical in multiple bones, which enhances their hunting success. The boreal owl's flight is relatively noiseless and straight.<ref name="svensson">{{cite book |last1=Svensson |first1=Lars |title=Collins Bird Guide |last2=Mullarney |first2=Killian |last3=Zetterström |first3=Dan |publisher=HarperCollins |year=2009 |isbn=978-0-00-726814-6 |edition=2nd |location=London |page=226}}</ref> |
|||
=== Juvenile identification === |
|||
| ⚫ | |||
Juvenile boreal owls, at about 3 weeks old, have a completely dull, chocolate-brown upperparts and underparts, with a dark brown facial disc bordered by black and white markings near the bill. Upon [[Fledge|fledging]], their plumage remains similar but with white markings on the neck, scapulars, flight feathers, and tail. They develop a broad white "X" between the eyes and distinct white streaks along the face, with cream-colored belly and flanks streaked in dark gray-brown.<ref name=":0" /> |
|||
=== Moults === |
|||
Boreal Owls have two primary [[moulting]] phases. The '''Prebasic I molt''' occurs around the age of two months, between August and September. It only affects the head, body, and wing coverts. The flight feathers, tertials, greater primary coverts, and tail are unaffected.<ref name=":1" /> The '''Definitive Prebasic molt''' is also partial, affecting all of the head, body, and wing coverts, as well as the tail, but only a portion of the flight feathers, which are replaced in a specific order each year. Males in Idaho moult from June to October, while females do so from May to October.<ref name=":1" /> |
|||
=== Vocalizations === |
|||
Vocalizations and related functions can be challenging to interpret because of their nocturnal and evasive lifestyle. Starting at one week old, young owls produce a harsh "peep" or "chirp" that softens after fledging. Comprehensive studies in North America has found 8 different types of vocalizations that play an important role in communication, mating, and territorial behaviour:<ref name=":2">Meehan, R. H. (1980). Behavioral significance of Boreal Owl vocalizations during breeding season. Master's Thesis, Univ. Alaska, Fairbanks.</ref><ref name=":3">{{Cite journal |last=Bondrup-Nielsen |first=S. |date=1984 |title=Vocalizations of the boreal owl, Aegolius funereus richardsoni, in North America |url=https://idfg.idaho.gov/species/bibliography/1503462 |journal=Canadian Field-Naturalist |volume=98 |issue=2 |pages=191–197|doi=10.5962/p.355125 |doi-access=free }}</ref> |
|||
* The '''Primary Song''' - loud trill sung by males to attract females and establish territory <ref name=":2" /> |
|||
* The '''Prolonged Song''' - softer courtship melody sung by males from beginning of courtship to incubation to strengthen bonds<ref name=":2" /> |
|||
* The '''Delivery Call''' - soft call by male to signal the transfer of prey to a female or young <ref name=":3" /> |
|||
* The '''Screech''' - a load contact call made while flying or from a perch <ref name=":2" /> |
|||
* The '''Peeping Call''' - soft vocalization by females throughout breeding to respond to males' calls |
|||
* The '''Weak Call''' - single note repeated rapidly from females in nest after hatching <ref name=":2" /> |
|||
* The '''Chuuk Call''' - harsh response call by females on male's territory <ref name=":3" /> |
|||
* The '''Hiss Call''' - defensive call by females when the nest is disturbed |
|||
Bill clapping is used as a protective sound by both adults and juveniles, and is frequently associated with vocal hiss. Young develop bill clapping at least one week before fledging. Adults reply with a bill clap when humans handle them or enter the nest cavity.<ref name=":0" /> |
|||
| ⚫ | Calls are similar in sound to the "winnowing" of the North American [[Wilson's snipe]].<ref>Alaska Department of Fish and Game The Boreal Owl. [http://www.adfg.alaska.gov/enwiki/static/education/wns/boreal_owl.pdf], Retrieved on May 10, 2013.</ref><ref>{{cite web |url=http://www.bcna.org/owls/Boreal_owl.html |title=Boulder County Nature Association |access-date=May 10, 2013}}</ref> |
||
==Distribution and habitat== |
==Distribution and habitat== |
||
The boreal owl breeds in dense [[Boreal forest of Canada|boreal,]] [[subalpine forest]] as well as [[mixed woodland]]. The preferred habitats are '''[[old-growth forest]]s''' as they provide shelter from avian predators and an abundant number of preys.<ref name=":4">{{Cite book |last1=Korpimäki |first1=Erkki |url=https://www.cambridge.org/core/product/identifier/9780511844164/type/book |title=The Boreal Owl: Ecology, Behaviour and Conservation of a Forest-Dwelling Predator |last2=Hakkarainen |first2=Harri |date=2012-09-27 |publisher=Cambridge University Press |isbn=978-0-511-84416-4 |edition=1 |doi=10.1017/cbo9780511844164}}</ref> Breeding habitats include boreal forests of black and white spruce,<ref name=":4" /> birch and aspen across northern North America and the [[Palearctic realm|Palearctic]], and in mountain ranges such as the [[Alps]] and the [[Rocky Mountains|Rockies]]. Nests can be found in aspen and mixed forests, while individuals roost in conifers of about 6 meters high.<ref name=":0" /> This species can travel long distances but are known to breed within 500 meters of their natal sites.<ref name=":0" /> Males have a higher site fidelity than females and occupy stable year-long home ranges. However, northern populations may [[Bird migration|migrate]] south in response to snow depth and poor prey availability, but eventually return to their breeding grounds.<ref>{{Cite journal |last1=Löfgren |first1=O. |last2=Hörnfeldt |first2=B. |last3=Carlsson |first3=B. -G. |date=1986-06-01 |title=Site tenacity and nomadism in Tengmalm's owl (Aegolius funereus (L.)) in relation to cyclic food production |url=https://link.springer.com/article/10.1007/BF00377051 |journal=Oecologia |language=en |volume=69 |issue=3 |pages=321–326 |doi=10.1007/BF00377051 |pmid=28311331 |bibcode=1986Oecol..69..321L |issn=1432-1939}}</ref><ref>{{Cite journal |last=Korpimäki |first=Erkki |date=1986-05-01 |title=Gradients in population fluctuations of Tengmalm's owl Aegolius funereus in Europe |url=https://link.springer.com/article/10.1007/BF00377621 |journal=Oecologia |language=en |volume=69 |issue=2 |pages=195–201 |doi=10.1007/BF00377621 |pmid=28311358 |bibcode=1986Oecol..69..195K |issn=1432-1939}}</ref><ref>{{Cite journal |last1=Sonerud |first1=Geir A. |last2=Solheim |first2=Roar |last3=Prestrud |first3=Kristen |date=1988 |title=Dispersal of Tengmalm's Owl Aegolius funereus in Relation to Prey Availability and Nesting Success |url=https://www.jstor.org/stable/3676555 |journal=Ornis Scandinavica (Scandinavian Journal of Ornithology) |volume=19 |issue=3 |pages=175–181 |doi=10.2307/3676555 |jstor=3676555 |issn=0030-5693}}</ref> |
|||
The boreal owl breeds in dense [[conifer]]ous forests across northern North America and the [[Palearctic]], and in mountain ranges such as the [[Alps]] and the [[Rocky Mountains|Rockies]]. This species is not normally [[bird migration|migratory]], but in some autumns significant numbers move further south. It is rarely any great distance south of its breeding range, although this is partly due to the problems of detecting this nocturnal owl outside the breeding season when it is not calling. |
|||
==Behaviour== |
==Behaviour== |
||
===Breeding=== |
===Breeding=== |
||
[[File:Aegolius funereus MWNH 0657.JPG|right|thumb|Egg, Collection [[Museum Wiesbaden]]]] |
[[File:Aegolius funereus MWNH 0657.JPG|right|thumb|Egg, Collection [[Museum Wiesbaden]]]] |
||
Boreal owls are [[Monogamy|monogamous]] and raise a single brood once they reach one year of age. The breeding begins with a lengthy courtship process where males sing for up to 102 days, starting from mid-February to mid-April, depending on environmental factors like prey availability and weather.<ref>{{Cite journal |last=Journal of Raptor Research |date=2024-01-06 |title=Habitat Selection, Movements and Activity of Boreal and Saw-whet Owls |url=https://digitalcommons.usf.edu/jrr/vol21/iss1/17/ |journal=Journal of Raptor Research |volume=21 |issue=1}}</ref> The nest is usually a hole in a tree often made by a woodpecker, but the birds also readily use [[Nest box|nest-boxes]]. Nesting period last for 28–36 days.<ref>Korpimaki, E. (1981). On the ecology and biology of Tengmalm's Owl (''Aegolius funereus'') in southern Ostrobothnia and Suomenselka, western Finland. Acta Univ. Ouluensis A 118 Biol. 13:1-84</ref> The clutch is usually 3-7 eggs which are laid at 2-day intervals. They are glossy white and measure {{cvt|33|x|26|mm}} and weigh around {{cvt|11.7|g}}. The eggs are incubated only by the female beginning with the second egg and incubation lasts on average 29 days for the first egg and 2.6 days less for the last one.<ref name=":0" /> They hatch asynchronously after 25–32 days. Females take care of the young and brood the nestlings for an average of 21 days. Food is brought by males during the first 3 weeks to the nest and female will tear apart the food for 2 weeks until young are able to eat unassisted. The young fledge after 28–36 days and become independent at 3 to 6 weeks outside the nest cavity.<ref>März, R. (1968). Der Rauhfusskauz. Wittenberg-Lutherstadt: Die Neue Brehm-Bücherei 394. |
|||
</ref><ref name=":0" /> Breeding densities fluctuate based on prey availability, ranging from 0.6 to 26 nests per square kilometer across different regions.<ref>Joneniaux, A. and G. Durand. (1987). Forest management and population ecology of Tengmalm's Owl. Rev. Ecol. Terre et la Vie, Supl. 4:84-87</ref><ref>{{Cite journal |last1=Korpimäki |first1=Erkki |last2=Norrdahl |first2=Kai |date=1989 |title=Predation of Tengmalm's Owls: Numerical Responses, Functional Responses and Dampening Impact on Population Fluctuations of Microtines |url=https://www.jstor.org/stable/3565261 |journal=Oikos |volume=54 |issue=2 |pages=154–164 |doi=10.2307/3565261 |jstor=3565261 |bibcode=1989Oikos..54..154K |issn=0030-1299}}</ref> |
|||
| ⚫ | |||
This small owl eats mainly [[vole]]s and other [[mammal]]s but also [[bird]]s as well as [[insect]]s and other invertebrates. It is largely [[nocturnal]], though in the northernmost parts of its range, it has to hunt during daylight because of the very short nights in summer. |
|||
| ⚫ | |||
This small owl eats mainly [[vole]]s and other [[mammal]]s (such as [[mice]], [[chipmunk]]s, other [[squirrel]]s, [[gopher]]s, [[Mole (animal)|mole]]s, [[shrew]]s and [[bat]]s),<ref name="Aegolius funereus Boreal owl">{{cite web | url=https://animaldiversity.org/accounts/Aegolius_funereus/ | title=Aegolius funereus (Boreal owl) | website=[[Animal Diversity Web]] }}</ref><ref name="peregrinefund.org">{{cite web | url=https://www.peregrinefund.org/explore-raptors-species/owls/boreal-owl | title=Boreal Owl | the Peregrine Fund }}</ref> but also [[bird]]s as well as small [[amphibian]]s,<ref name="peregrinefund.org"/> [[insect]]s (such as [[beetle]]s)<ref name="peregrinefund.org"/> and other invertebrates. In North America, they have been observed preying on [[southern red-backed vole]]s, [[western heather vole|western heather voles,]] [[Zapus|jumping mice]], [[northern pocket gopher]]s and [[northern flying squirrel]]s.<ref name="Aegolius funereus Boreal owl"/> Birds preyed upon include [[dark-eyed junco]]s, [[American robin]]s and [[common redpoll]]s.<ref name="Aegolius funereus Boreal owl"/> It is largely [[nocturnal]], though in the northernmost parts of its range, it has to hunt during daylight because of the very short nights in summer. This species is a [[Ambush predator|sit-and-wait]] predator meaning it does not pursue animals within 10 meters of its hunting perch. Their extreme asymmetrical skulls leads to sound localization in both horizontal and vertical directions and allow them to capture preys under snow and dense vegetation.<ref>{{Cite journal |date=1978-03-09 |title=Skull asymmetry, ear structure and function, and auditory localization in Tengmalm's owl, Aegolius funereus (Linné) |url=https://royalsocietypublishing.org/doi/10.1098/rstb.1978.0014 |journal=Philosophical Transactions of the Royal Society of London. B, Biological Sciences |language=en |volume=282 |issue=991 |pages=325–410 |doi=10.1098/rstb.1978.0014 |bibcode=1978RSPTB.282..325N |issn=0080-4622 |last1=Norberg |first1=R. A. }}</ref> |
|||
=== Threats === |
|||
==== Biological resource use - timber harvest ==== |
|||
Logging activities have a negative impact on prey availability, foraging efficiency and suitable nesting sites.<ref>{{Citation |last1=Holt |first1=Denver W. |title=Buff-fronted Owl (Aegolius harrisii) |date=2020-03-04 |work=Birds of the World |url=http://dx.doi.org/10.2173/bow.bufowl1.01 |access-date=2024-10-14 |publisher=Cornell Lab of Ornithology |last2=Berkley |first2=Regan |last3=Deppe |first3=Caroline |last4=Enríquez |first4=Paula L. |last5=Petersen |first5=Julie L. |last6=Rangel Salazar |first6=José Luis |last7=Segars |first7=Kelley P. |last8=Wood |first8=Kristin L. |last9=Bonan |first9=Arnau|editor-first1=Josep |editor-first2=Andrew |editor-first3=Jordi |editor-first4=David |editor-first5=Eduardo |editor-last1=Del Hoyo |editor-last2=Elliott |editor-last3=Sargatal |editor-last4=Christie |editor-last5=De Juana |doi=10.2173/bow.bufowl1.01 }}</ref> Since the 1990s, significant population declines in northern Europe have been attributed to [[Clearcutting|clear-cutting]]. Moreover, pesticides from agriculture and forestry effluents are damaging to the species' health.<ref>{{Cite book |last=König, Claus, and Weick |title=Owls of the world |date=2008 |publisher=A&C Black}}</ref> The slow forest succession in spruce-fir ecosystems disrupts the recovery of critical habitat which impacts the species' ability to thrive.<ref name=":4" /> The [[Black woodpecker|black woodpecker (''Dryocopus martius'')]] population decline in Eurasia has also led to a reduced number of nesting cavities.<ref>{{Cite book |last=Mikkola |first=Heimo Juhani |title=Owls of Europe |date=January 1983 |publisher=A.D. & T. Poyser |year=1983 |isbn=0-85661-034-8 |edition=1st}}</ref> |
|||
==== Predation ==== |
|||
[[Marten]] species (Martes spp.) and [[Tawny owl|tawny owls (''Strix aluco'')]] are the predominant predators of boreal owl owlets and adult females at nest locations, with martens preying on 48% of Norwegian clutches.<ref>{{Cite journal |last=Sonerud |first=G. A. |date=1985 |title=Nest Hole Shift in Tengmalm's Owl Aegolius funereus as Defence Against Nest Predation Involving Long-Term Memory in the Predator |journal=The Journal of Animal Ecology |volume=54 |issue=1 |pages=179–192 |doi=10.2307/4629|jstor=4629 |bibcode=1985JAnEc..54..179S |s2cid=86967254 }}</ref> Other predators include [[pine squirrel]]s (''Tamiasciurus hudsonicus''), [[cooper's hawk]] (''Astur cooperii)'', [[Northern goshawk|northern Goshawk]], [[great horned owl]] (''Bubo virginianus)'' and [[ural owl]] (''Strix uralensis'').<ref>{{Cite journal |last1=Herrera |first1=Carlos M. |last2=Hiraldo |first2=Fernando |date=1976 |title=Food-Niche and Trophic Relationships among European Owls |url=https://www.jstor.org/stable/3676172 |journal=Ornis Scandinavica (Scandinavian Journal of Ornithology) |volume=7 |issue=1 |pages=29–41 |doi=10.2307/3676172 |jstor=3676172 |issn=0030-5693}}</ref> Moreover, [[nuthatch]]es (''Sitta europaea'') have been observed blocking the entrance of nests with mud, occasionally trapping females inside and starving them to death. |
|||
===Mortality=== |
===Mortality=== |
||
Boreal owl mortality rates vary by region and age. In Idaho, adult annual survival rate was 46%,<ref>{{Cite book |last1=Piorecky |first1=Mark D. |url=http://dx.doi.org/10.5962/bhl.title.113788 |title=Distribution, abundance and habitat selection of northern pygmy and barred owls along the Eastern Slopes of the Alberta Rocky Mountains / |last2=Prescott |first2=David R. C. |date=2004 |publisher=Alberta Sustainable Resource Development, Fish & Wildlife Division, Resource Data and Species at Risk Section |location=[Edmonton]|doi=10.5962/bhl.title.113788 }}</ref> while in Finland, first-year males had a survival rate of 50%, and adult males 67%. Most fledgling males (78%) died before their first breeding attempt.<ref>{{Cite journal |last=Korpimäki |first=Erkki |date=1992 |title=Fluctuating Food Abundance Determines the Lifetime Reproductive Success of Male Tengmalm's Owls |url=https://www.jstor.org/stable/5513 |journal=Journal of Animal Ecology |volume=61 |issue=1 |pages=103–111 |doi=10.2307/5513 |jstor=5513 |bibcode=1992JAnEc..61..103K |issn=0021-8790}}</ref> Overall, adult survival ranges from '''62% to 72%''' across studies.<ref>{{Cite journal |last1=Sonerud |first1=Geir A. |last2=Solheim |first2=Roar |last3=Prestrud |first3=Kristen |date=1988 |title=Dispersal of Tengmalm's Owl Aegolius funereus in Relation to Prey Availability and Nesting Success |url=http://dx.doi.org/10.2307/3676555 |journal=Ornis Scandinavica |volume=19 |issue=3 |pages=175 |doi=10.2307/3676555 |jstor=3676555 |issn=0030-5693}}</ref><ref>{{Cite journal |last=Korpimäki |first=Erkki |date=1986 |title=Gradients in population fluctuations of Tengmalm's owl Aegolius funereus in Europe |url=http://dx.doi.org/10.1007/bf00377621 |journal=Oecologia |volume=69 |issue=2 |pages=195–201 |doi=10.1007/bf00377621 |pmid=28311358 |bibcode=1986Oecol..69..195K |issn=0029-8549}}</ref> Moreover, the average lifespan of breeding males is 3.5 years, and can go up to 11 years. [[Bird ringing|Banded]] boreal owls have been known to live up to 16 years. |
|||
[[Bird ringing|Banded]] boreal owls have been known to live up to 16 years. Due to the owl's small stature it is often eaten by other owls and large raptors thus decreasing its average life span. |
|||
== Relationship to humans == |
|||
Owls have played an important role in myths and cultural belief, seen as both feared and worshiped creatures.<ref name=":5">{{Cite web |last=Cocker |first=Bruce Marcot, David Johnson, Mark |title=Owls in Lore and Culture (Page 2 of 3) |url=https://www.owlpages.com/owls/articles.php?a=64&p=2 |access-date=2024-10-15 |website=The Owl Pages |language=en}}</ref> They are linked to death and seen as messengers between the living and the dead among Native Americans and the mountain tribes of Myanmar. In India, they are linked to cemeteries and are believed to keep the spirit of the deceased. However, they are associated to good fortune in Hindu mythology.<ref name=":5" /> Furthermore, owls were important in art and symbolism in East Central Europe, especially the Pavlovian culture. Their appearance in art reflect a deep bond between humans and owls, based on shared environment and a strong "sense of place."<ref>{{Cite journal |last=Hussain |first=Shumon T. |date=2019-10-02 |title=Gazing at Owls? Human-strigiform Interfaces and their Role in the Construction of Gravettian Lifeworlds in East-Central Europe |url=https://www.tandfonline.com/doi/full/10.1080/14614103.2018.1434854 |journal=Environmental Archaeology |language=en |volume=24 |issue=4 |pages=359–376 |doi=10.1080/14614103.2018.1434854 |bibcode=2019EnvAr..24..359H |issn=1461-4103|hdl=1887/72082 |hdl-access=free }}</ref> |
|||
== Conservation status == |
|||
The current population trend is stable with 730,000 - 1,810,000 mature individuals: the species is currently listed under '''Least Concerned''' under CITES Appendix II, the EU Birds Directive Appendix I, and Raptors MOU Category 3.<ref name="iucn status 12 November 2021"/> Nevertheless, the species' lifestyle makes it hard to monitor the decline in some subpopulations. The USDA Forest Service Regions 1, 2, 3, 4 and 9 designated the species as a "sensitive species".<ref name=":0" /> In Europe, systematic breeding surveys are being conducted in order to monitor its population status.<ref>{{Cite book |last=Ornithology |first=British Trust for |url=https://www.bto.org/our-science/publications/peer-reviewed-papers/review-raptor-and-owl-monitoring-activity-across |title=A review of raptor and owl monitoring activity across Europe: its implications for capacity building towards pan-European monitoring |date=2019-03-21 |language=en}}</ref> Nest boxes are implemented to create suitable nesting sites and ensure reproductive success.<ref name=":4" /> The preservation of old-growth forests - with selective tree harvest to allow tree removal while maintaining suitable habitats <ref name=":0" /> - and protection [[black woodpecker]]s (''Dryocopus martius''), that provide nesting cavities, are mandatory for the species' long-term survival. |
|||
==References== |
==References== |
||
| Line 69: | Line 115: | ||
==Sources== |
==Sources== |
||
{{refbegin}} |
{{refbegin}} |
||
*{{ cite book | editor1-last=Cramp | editor1-first=Stanley | editor1-link=Stanley Cramp | year=1985 | chapter=''Aegolius funereus'' Tengmalm's Owl | title=Handbook of the Birds of Europe the Middle East and North Africa. The Birds of the Western Palearctic | volume=IV: Terns to Woodpeckers | location=Oxford | publisher=Oxford University Press | pages= |
*{{ cite book | editor1-last=Cramp | editor1-first=Stanley | editor1-link=Stanley Cramp | year=1985 | chapter=''Aegolius funereus'' Tengmalm's Owl | title=Handbook of the Birds of Europe the Middle East and North Africa. The Birds of the Western Palearctic | volume=IV: Terns to Woodpeckers | location=Oxford | publisher=Oxford University Press | pages=606–616 | isbn=978-0-19-857507-8 }} |
||
{{refend}} |
{{refend}} |
||
Latest revision as of 17:16, 6 November 2024
| Boreal owl | |
|---|---|
| |
| Amherst Island, Ontario, Canada | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Strigiformes |
| Family: | Strigidae |
| Genus: | Aegolius |
| Species: | A. funereus
|
| Binomial name | |
| Aegolius funereus | |
| Subspecies | |
|
7, see text | |
| |
| Range of A. funereus
Resident Non-breeding
| |
| Synonyms[3] | |
| |
The boreal owl (Aegolius funereus) or Tengmalm's owl is a small owl in the "true owl" family Strigidae. It is known as the boreal owl in North America and as Tengmalm's owl in Europe after Swedish naturalist Peter Gustaf Tengmalm or, more rarely, Richardson's owl after Sir John Richardson.[3][4]
Due to the boreal owl's shyness and evasive reaction to human activities, nocturnal habits and preferred inaccessible taiga forest habitat, it is rarely seen by humans.
Taxonomy
[edit]The boreal owl was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae. Linnaeus placed it with all the other owls in the genus Strixand coined the binomial name Strix funerea.[5] The Eurasian scops owl is now placed in the genus Aegolius that was introduced in 1829 by the German naturalist Johann Jakob Kaup with the boreal owl as the type species.[6][7] The genus name is Latin for a screech owl, the word came from the Ancient Greek aigōlios meaning "a bird of ill omen". The specific epithet funereus is Latin meaning "funereal".[8]
Related species
[edit]Congeners include northern saw-whet owl (A. acadicus), unspotted saw-whet owl (A. ridgwayi), and buff-fronted owl (A. harrisii), all found in the New World.[9]
Subspecies
[edit]Seven subspecies are recognized:[7]
- A.f. richardsoni (Bonaparte, 1838) – Alaska, north Canada and north United States
- A.f funereus (Linnaeus, 1758) – nominate subspecies, from Scandinavia down south to the Pyrenees and east to the Urals, but not the Caucasus Mountains
- A.f. magnus (Buturlin, 1907) – northeast Siberia
- A.f. sibiricus (Buturlin, 1910) – southeast and south Siberia
- A.f. pallens (Schalow, 1908) – west and central Siberia
- A.f. caucasicus (Buturlin, 1907) – Caucasus Mountains
- A.f. beickianus Stresemann, 1928 – northwest India to southwest China
Fossil History
[edit]Remains of the boreal owl dating back to the Pleistocene era were found in a cave in southern New Mexico.[10] Bones were found in a pueblo in north-central New Mexico that has been inhabited from around A.D. 1250 to the present.[11]
Description
[edit]The boreal owl is small with a large head and long wings. Both sexes are similar in appearance, though females are larger. Males typically measure 21–25 cm (8.3-9.8 in) in length, with a wingspan of 55–58 cm (21.7-22.8 in), while females are larger – 25–28 cm (9.8–11 in) – with a wingspan of 59–62 cm (23.2-24.4 in). A female is heavier than a male bird and weighs 132-215 g (4.7-7.6 oz) compared to 93-139 g (3.3-4.9 oz) for a male bird.
Adult identification
[edit]The plumage is brown above, with white flecking on the shoulders and whitish underparts with rust-colored streaks. Its large head has yellow eyes and an olive-brown crown with small white droplets and larger central spots. The dull white facial disc is framed with a dark border and white “eyebrows” often described as giving the owl a "surprised" expression. The underparts are cream-white with russet-brown streaks, while the tail has olive-brown feathers with narrow bars. Flight feathers are dark olive-brown with contrasting white spots. The primaries typically have up to five rows of white spots, while the tail has three distinct rows of spots.[9] Unlike other owl species, these spots remain separated even when the tail is folded closely together.[12] The beak is light yellow, rather than dark like its relative the northern saw-whet owl.[13] The ears are asymmetrical in multiple bones, which enhances their hunting success. The boreal owl's flight is relatively noiseless and straight.[14]
Juvenile identification
[edit]
Juvenile boreal owls, at about 3 weeks old, have a completely dull, chocolate-brown upperparts and underparts, with a dark brown facial disc bordered by black and white markings near the bill. Upon fledging, their plumage remains similar but with white markings on the neck, scapulars, flight feathers, and tail. They develop a broad white "X" between the eyes and distinct white streaks along the face, with cream-colored belly and flanks streaked in dark gray-brown.[9]
Moults
[edit]Boreal Owls have two primary moulting phases. The Prebasic I molt occurs around the age of two months, between August and September. It only affects the head, body, and wing coverts. The flight feathers, tertials, greater primary coverts, and tail are unaffected.[12] The Definitive Prebasic molt is also partial, affecting all of the head, body, and wing coverts, as well as the tail, but only a portion of the flight feathers, which are replaced in a specific order each year. Males in Idaho moult from June to October, while females do so from May to October.[12]
Vocalizations
[edit]Vocalizations and related functions can be challenging to interpret because of their nocturnal and evasive lifestyle. Starting at one week old, young owls produce a harsh "peep" or "chirp" that softens after fledging. Comprehensive studies in North America has found 8 different types of vocalizations that play an important role in communication, mating, and territorial behaviour:[15][16]
- The Primary Song - loud trill sung by males to attract females and establish territory [15]
- The Prolonged Song - softer courtship melody sung by males from beginning of courtship to incubation to strengthen bonds[15]
- The Delivery Call - soft call by male to signal the transfer of prey to a female or young [16]
- The Screech - a load contact call made while flying or from a perch [15]
- The Peeping Call - soft vocalization by females throughout breeding to respond to males' calls
- The Weak Call - single note repeated rapidly from females in nest after hatching [15]
- The Chuuk Call - harsh response call by females on male's territory [16]
- The Hiss Call - defensive call by females when the nest is disturbed
Bill clapping is used as a protective sound by both adults and juveniles, and is frequently associated with vocal hiss. Young develop bill clapping at least one week before fledging. Adults reply with a bill clap when humans handle them or enter the nest cavity.[9]
Calls are similar in sound to the "winnowing" of the North American Wilson's snipe.[17][18]
Distribution and habitat
[edit]The boreal owl breeds in dense boreal, subalpine forest as well as mixed woodland. The preferred habitats are old-growth forests as they provide shelter from avian predators and an abundant number of preys.[19] Breeding habitats include boreal forests of black and white spruce,[19] birch and aspen across northern North America and the Palearctic, and in mountain ranges such as the Alps and the Rockies. Nests can be found in aspen and mixed forests, while individuals roost in conifers of about 6 meters high.[9] This species can travel long distances but are known to breed within 500 meters of their natal sites.[9] Males have a higher site fidelity than females and occupy stable year-long home ranges. However, northern populations may migrate south in response to snow depth and poor prey availability, but eventually return to their breeding grounds.[20][21][22]
Behaviour
[edit]Breeding
[edit]
Boreal owls are monogamous and raise a single brood once they reach one year of age. The breeding begins with a lengthy courtship process where males sing for up to 102 days, starting from mid-February to mid-April, depending on environmental factors like prey availability and weather.[23] The nest is usually a hole in a tree often made by a woodpecker, but the birds also readily use nest-boxes. Nesting period last for 28–36 days.[24] The clutch is usually 3-7 eggs which are laid at 2-day intervals. They are glossy white and measure 33 mm × 26 mm (1.3 in × 1.0 in) and weigh around 11.7 g (0.41 oz). The eggs are incubated only by the female beginning with the second egg and incubation lasts on average 29 days for the first egg and 2.6 days less for the last one.[9] They hatch asynchronously after 25–32 days. Females take care of the young and brood the nestlings for an average of 21 days. Food is brought by males during the first 3 weeks to the nest and female will tear apart the food for 2 weeks until young are able to eat unassisted. The young fledge after 28–36 days and become independent at 3 to 6 weeks outside the nest cavity.[25][9] Breeding densities fluctuate based on prey availability, ranging from 0.6 to 26 nests per square kilometer across different regions.[26][27]
Food and feeding behaviour
[edit]This small owl eats mainly voles and other mammals (such as mice, chipmunks, other squirrels, gophers, moles, shrews and bats),[28][29] but also birds as well as small amphibians,[29] insects (such as beetles)[29] and other invertebrates. In North America, they have been observed preying on southern red-backed voles, western heather voles, jumping mice, northern pocket gophers and northern flying squirrels.[28] Birds preyed upon include dark-eyed juncos, American robins and common redpolls.[28] It is largely nocturnal, though in the northernmost parts of its range, it has to hunt during daylight because of the very short nights in summer. This species is a sit-and-wait predator meaning it does not pursue animals within 10 meters of its hunting perch. Their extreme asymmetrical skulls leads to sound localization in both horizontal and vertical directions and allow them to capture preys under snow and dense vegetation.[30]
Threats
[edit]Biological resource use - timber harvest
[edit]Logging activities have a negative impact on prey availability, foraging efficiency and suitable nesting sites.[31] Since the 1990s, significant population declines in northern Europe have been attributed to clear-cutting. Moreover, pesticides from agriculture and forestry effluents are damaging to the species' health.[32] The slow forest succession in spruce-fir ecosystems disrupts the recovery of critical habitat which impacts the species' ability to thrive.[19] The black woodpecker (Dryocopus martius) population decline in Eurasia has also led to a reduced number of nesting cavities.[33]
Predation
[edit]Marten species (Martes spp.) and tawny owls (Strix aluco) are the predominant predators of boreal owl owlets and adult females at nest locations, with martens preying on 48% of Norwegian clutches.[34] Other predators include pine squirrels (Tamiasciurus hudsonicus), cooper's hawk (Astur cooperii), northern Goshawk, great horned owl (Bubo virginianus) and ural owl (Strix uralensis).[35] Moreover, nuthatches (Sitta europaea) have been observed blocking the entrance of nests with mud, occasionally trapping females inside and starving them to death.
Mortality
[edit]Boreal owl mortality rates vary by region and age. In Idaho, adult annual survival rate was 46%,[36] while in Finland, first-year males had a survival rate of 50%, and adult males 67%. Most fledgling males (78%) died before their first breeding attempt.[37] Overall, adult survival ranges from 62% to 72% across studies.[38][39] Moreover, the average lifespan of breeding males is 3.5 years, and can go up to 11 years. Banded boreal owls have been known to live up to 16 years.
Relationship to humans
[edit]Owls have played an important role in myths and cultural belief, seen as both feared and worshiped creatures.[40] They are linked to death and seen as messengers between the living and the dead among Native Americans and the mountain tribes of Myanmar. In India, they are linked to cemeteries and are believed to keep the spirit of the deceased. However, they are associated to good fortune in Hindu mythology.[40] Furthermore, owls were important in art and symbolism in East Central Europe, especially the Pavlovian culture. Their appearance in art reflect a deep bond between humans and owls, based on shared environment and a strong "sense of place."[41]
Conservation status
[edit]The current population trend is stable with 730,000 - 1,810,000 mature individuals: the species is currently listed under Least Concerned under CITES Appendix II, the EU Birds Directive Appendix I, and Raptors MOU Category 3.[1] Nevertheless, the species' lifestyle makes it hard to monitor the decline in some subpopulations. The USDA Forest Service Regions 1, 2, 3, 4 and 9 designated the species as a "sensitive species".[9] In Europe, systematic breeding surveys are being conducted in order to monitor its population status.[42] Nest boxes are implemented to create suitable nesting sites and ensure reproductive success.[19] The preservation of old-growth forests - with selective tree harvest to allow tree removal while maintaining suitable habitats [9] - and protection black woodpeckers (Dryocopus martius), that provide nesting cavities, are mandatory for the species' long-term survival.
References
[edit]- ^ a b BirdLife International (2021). "Aegolius funereus". IUCN Red List of Threatened Species. 2021: e.T22689362A201898946. doi:10.2305/IUCN.UK.2021-3.RLTS.T22689362A201898946.en. Retrieved 12 November 2021.
- ^ "Appendices | CITES". cites.org. Retrieved 2022-01-14.
- ^ a b "Aegolius funereus". Avibase.
- ^ Beolens, Bo; Watkins, Michael (2003). Whose bird?: Men and women commemorated in the common names of birds. London: Helm. ISBN 0713666471.
- ^ Linnaeus, Carl (1758). Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (in Latin). Vol. 1 (10th ed.). Holmiae (Stockholm): Laurentii Salvii. p. 93.
- ^ Kaup, Johann Jakob (1829). Skizzirte Entwickelungs-Geschichte und natürliches System der europäischen Thierwelt (in German). Vol. c. 1. Darmstadt: Carl Wilhelm Leske. p. 34.
- ^ a b Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (January 2022). "Owls". IOC World Bird List Version 12.1. International Ornithologists' Union. Retrieved 2 March 2022.
- ^ Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. pp. 33, 166. ISBN 978-1-4081-2501-4.
- ^ a b c d e f g h i j Hayward, G. D.; Hayward, P. H. (2020-03-04), Billerman, Shawn M. (ed.), "Boreal Owl (Aegolius funereus)", Birds of the World, Cornell Lab of Ornithology, doi:10.2173/bow.borowl.01, retrieved 2024-10-14
- ^ "Google Scholar". scholar.google.com. Retrieved 2024-10-14.
- ^ Emslie, Steven D. (1981-09-01). "Birds and prehistoric agriculture: The New Mexican pueblos". Human Ecology. 9 (3): 305–329. Bibcode:1981HumEc...9..305E. doi:10.1007/BF00890740. ISSN 1572-9915.
- ^ a b c Handbook of the birds of Europe the Middle East and North Africa: the birds of the Western Palearctic. Oxford [u.a.]: Oxford University Press. 1977.
- ^ Bull, Farrand (1994). National Audubon Society Field Guide to North American Birds: Eastern Region. New York: Alfred A. Knopf. p. 554. ISBN 0-679-42852-6.
- ^ Svensson, Lars; Mullarney, Killian; Zetterström, Dan (2009). Collins Bird Guide (2nd ed.). London: HarperCollins. p. 226. ISBN 978-0-00-726814-6.
- ^ a b c d e Meehan, R. H. (1980). Behavioral significance of Boreal Owl vocalizations during breeding season. Master's Thesis, Univ. Alaska, Fairbanks.
- ^ a b c Bondrup-Nielsen, S. (1984). "Vocalizations of the boreal owl, Aegolius funereus richardsoni, in North America". Canadian Field-Naturalist. 98 (2): 191–197. doi:10.5962/p.355125.
- ^ Alaska Department of Fish and Game The Boreal Owl. [1], Retrieved on May 10, 2013.
- ^ "Boulder County Nature Association". Retrieved May 10, 2013.
- ^ a b c d Korpimäki, Erkki; Hakkarainen, Harri (2012-09-27). The Boreal Owl: Ecology, Behaviour and Conservation of a Forest-Dwelling Predator (1 ed.). Cambridge University Press. doi:10.1017/cbo9780511844164. ISBN 978-0-511-84416-4.
- ^ Löfgren, O.; Hörnfeldt, B.; Carlsson, B. -G. (1986-06-01). "Site tenacity and nomadism in Tengmalm's owl (Aegolius funereus (L.)) in relation to cyclic food production". Oecologia. 69 (3): 321–326. Bibcode:1986Oecol..69..321L. doi:10.1007/BF00377051. ISSN 1432-1939. PMID 28311331.
- ^ Korpimäki, Erkki (1986-05-01). "Gradients in population fluctuations of Tengmalm's owl Aegolius funereus in Europe". Oecologia. 69 (2): 195–201. Bibcode:1986Oecol..69..195K. doi:10.1007/BF00377621. ISSN 1432-1939. PMID 28311358.
- ^ Sonerud, Geir A.; Solheim, Roar; Prestrud, Kristen (1988). "Dispersal of Tengmalm's Owl Aegolius funereus in Relation to Prey Availability and Nesting Success". Ornis Scandinavica (Scandinavian Journal of Ornithology). 19 (3): 175–181. doi:10.2307/3676555. ISSN 0030-5693. JSTOR 3676555.
- ^ Journal of Raptor Research (2024-01-06). "Habitat Selection, Movements and Activity of Boreal and Saw-whet Owls". Journal of Raptor Research. 21 (1).
- ^ Korpimaki, E. (1981). On the ecology and biology of Tengmalm's Owl (Aegolius funereus) in southern Ostrobothnia and Suomenselka, western Finland. Acta Univ. Ouluensis A 118 Biol. 13:1-84
- ^ März, R. (1968). Der Rauhfusskauz. Wittenberg-Lutherstadt: Die Neue Brehm-Bücherei 394.
- ^ Joneniaux, A. and G. Durand. (1987). Forest management and population ecology of Tengmalm's Owl. Rev. Ecol. Terre et la Vie, Supl. 4:84-87
- ^ Korpimäki, Erkki; Norrdahl, Kai (1989). "Predation of Tengmalm's Owls: Numerical Responses, Functional Responses and Dampening Impact on Population Fluctuations of Microtines". Oikos. 54 (2): 154–164. Bibcode:1989Oikos..54..154K. doi:10.2307/3565261. ISSN 0030-1299. JSTOR 3565261.
- ^ a b c "Aegolius funereus (Boreal owl)". Animal Diversity Web.
- ^ a b c "Boreal Owl | the Peregrine Fund".
- ^ Norberg, R. A. (1978-03-09). "Skull asymmetry, ear structure and function, and auditory localization in Tengmalm's owl, Aegolius funereus (Linné)". Philosophical Transactions of the Royal Society of London. B, Biological Sciences. 282 (991): 325–410. Bibcode:1978RSPTB.282..325N. doi:10.1098/rstb.1978.0014. ISSN 0080-4622.
- ^ Holt, Denver W.; Berkley, Regan; Deppe, Caroline; Enríquez, Paula L.; Petersen, Julie L.; Rangel Salazar, José Luis; Segars, Kelley P.; Wood, Kristin L.; Bonan, Arnau (2020-03-04), Del Hoyo, Josep; Elliott, Andrew; Sargatal, Jordi; Christie, David; De Juana, Eduardo (eds.), "Buff-fronted Owl (Aegolius harrisii)", Birds of the World, Cornell Lab of Ornithology, doi:10.2173/bow.bufowl1.01, retrieved 2024-10-14
- ^ König, Claus, and Weick (2008). Owls of the world. A&C Black.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ Mikkola, Heimo Juhani (January 1983). Owls of Europe (1st ed.). A.D. & T. Poyser. ISBN 0-85661-034-8.
{{cite book}}: CS1 maint: date and year (link) - ^ Sonerud, G. A. (1985). "Nest Hole Shift in Tengmalm's Owl Aegolius funereus as Defence Against Nest Predation Involving Long-Term Memory in the Predator". The Journal of Animal Ecology. 54 (1): 179–192. Bibcode:1985JAnEc..54..179S. doi:10.2307/4629. JSTOR 4629. S2CID 86967254.
- ^ Herrera, Carlos M.; Hiraldo, Fernando (1976). "Food-Niche and Trophic Relationships among European Owls". Ornis Scandinavica (Scandinavian Journal of Ornithology). 7 (1): 29–41. doi:10.2307/3676172. ISSN 0030-5693. JSTOR 3676172.
- ^ Piorecky, Mark D.; Prescott, David R. C. (2004). Distribution, abundance and habitat selection of northern pygmy and barred owls along the Eastern Slopes of the Alberta Rocky Mountains /. [Edmonton]: Alberta Sustainable Resource Development, Fish & Wildlife Division, Resource Data and Species at Risk Section. doi:10.5962/bhl.title.113788.
- ^ Korpimäki, Erkki (1992). "Fluctuating Food Abundance Determines the Lifetime Reproductive Success of Male Tengmalm's Owls". Journal of Animal Ecology. 61 (1): 103–111. Bibcode:1992JAnEc..61..103K. doi:10.2307/5513. ISSN 0021-8790. JSTOR 5513.
- ^ Sonerud, Geir A.; Solheim, Roar; Prestrud, Kristen (1988). "Dispersal of Tengmalm's Owl Aegolius funereus in Relation to Prey Availability and Nesting Success". Ornis Scandinavica. 19 (3): 175. doi:10.2307/3676555. ISSN 0030-5693. JSTOR 3676555.
- ^ Korpimäki, Erkki (1986). "Gradients in population fluctuations of Tengmalm's owl Aegolius funereus in Europe". Oecologia. 69 (2): 195–201. Bibcode:1986Oecol..69..195K. doi:10.1007/bf00377621. ISSN 0029-8549. PMID 28311358.
- ^ a b Cocker, Bruce Marcot, David Johnson, Mark. "Owls in Lore and Culture (Page 2 of 3)". The Owl Pages. Retrieved 2024-10-15.
{{cite web}}: CS1 maint: multiple names: authors list (link) - ^ Hussain, Shumon T. (2019-10-02). "Gazing at Owls? Human-strigiform Interfaces and their Role in the Construction of Gravettian Lifeworlds in East-Central Europe". Environmental Archaeology. 24 (4): 359–376. Bibcode:2019EnvAr..24..359H. doi:10.1080/14614103.2018.1434854. hdl:1887/72082. ISSN 1461-4103.
- ^ Ornithology, British Trust for (2019-03-21). A review of raptor and owl monitoring activity across Europe: its implications for capacity building towards pan-European monitoring.
Sources
[edit]- Cramp, Stanley, ed. (1985). "Aegolius funereus Tengmalm's Owl". Handbook of the Birds of Europe the Middle East and North Africa. The Birds of the Western Palearctic. Vol. IV: Terns to Woodpeckers. Oxford: Oxford University Press. pp. 606–616. ISBN 978-0-19-857507-8.
External links
[edit]
Wikimedia Commons has media related to Aegolius funereus.
Wikispecies has information related to Aegolius funereus.
- "Boreal Owl media". Internet Bird Collection.
- "Aegolius funereus". Integrated Taxonomic Information System. Retrieved 24 February 2009.
- Aegolius funereus in Field Guide: Birds of the World on Flickr
- "Aegolius funereus". Avibase.
- Boreal Owl photo gallery at VIREO (Drexel University)
