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Revision as of 15:10, 11 February 2022 edit90.248.112.244 (talk) Included reference to male-female differences in diving behaviourTag: Visual edit← Previous edit Latest revision as of 23:12, 26 December 2024 edit undoEsplanader1871 (talk | contribs)17 editsm Clarified that population which died off, according to the source material, was in Alaska. The article did refer to the die off of the total world population.Tags: Visual edit Mobile edit Mobile web edit 
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{{Short description|Species of bird}} {{Short description|Species of bird}}
{{Speciesbox {{Speciesbox
| name = Common Murre
| image = Common Murre Uria aalge.jpg | image = Common Murre Uria aalge.jpg
| image_caption = ], Wales]] | image2 = Common Guillemot (Uria aalge) (W1CDR0001424 BD6).ogg
| image2_caption = Bird calls recorded in ], Wales
| status = LC | status = LC
| status_system = IUCN3.1 | status_system = IUCN3.1
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}} }}


The '''common murre''' or '''common guillemot''' (''Uria aalge'') is a large ]. It has a ] distribution, occurring in low-Arctic and boreal waters in the North ] and North ]. It spends most of its time at sea, only coming to land to breed on rocky cliff shores or islands. The '''common murre''' or '''common guillemot''' ('''''Uria aalge''''') is a large ]. It has a ] distribution, occurring in low-Arctic and boreal waters in the North ] and North ]. It spends most of its time at sea, only coming to land to breed on rocky cliff shores or islands.


Common murres have fast direct flight but are not very agile. They are more maneuverable underwater, typically diving to depths of {{convert|30|-|60|m|ft|round=5|abbr=on}}. Depths of up to {{convert|180|m|ft|-1|abbr=on}} have been recorded. Common murres are fast in direct flight but are not very agile. They are highly mobile underwater using their wings to 'fly' through the water column, where they typically dive to depths of {{convert|30|-|60|m|ft|round=5|abbr=on}}. Depths of up to {{convert|180|m|ft|-1|abbr=on}} have been recorded.


Common murres breed in ] at high densities. Nesting pairs may be in bodily contact with their neighbours. They make no nest; their single egg is ] on a bare rock ledge on a cliff face. Eggs hatch after ~30 days incubation. The chick is born ] and can regulate its body temperature after 10 days. Some 20 days after hatching the chick leaves its nesting ledge and heads for the sea, unable to fly, but gliding for some distance with fluttering wings, accompanied by its male parent.<ref>{{Cite journal|last1=Harris|first1=M. P.|last2=Wanless|first2=S.|last3=Barton|first3=T. R.|last4=Elston|first4=D. A.|date=1997|title=Nest site characteristics, duration of use and breeding success in the Guillemot Uria aalge|journal=Ibis|volume=139|issue=3|pages=468–476|doi=10.1111/j.1474-919x.1997.tb04660.x|issn=0019-1019}}</ref> Male guillemots spend more time diving, and dive more deeply than females during this time <ref>{{Cite journal|last=Dunn|first=Ruth E.|last2=Wanless|first2=Sarah|last3=Green|first3=Jonathan A.|last4=Harris|first4=Michael P.|last5=Daunt|first5=Francis|date=2019|title=Effects of body size, sex, parental care and moult strategies on auk diving behaviour outside the breeding season|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/jav.02012|journal=Journal of Avian Biology|language=en|volume=50|issue=7|doi=10.1111/jav.02012|issn=1600-048X}}</ref>. Chicks are capable of diving as soon as they hit the water. The female stays at the nest site for some 14 days after the chick has left. Common murres breed in ] at high densities. Nesting pairs may be in bodily contact with their neighbours. They make no nest; their single egg is ] between the adult's feet on a bare rock ledge on a cliff face. Eggs hatch after ~30 days incubation. The chick is born ] and can regulate its body temperature after 10 days. Some 20 days after hatching the chick leaves its nesting ledge and heads for the sea, unable to fly, but gliding for some distance with fluttering wings, accompanied by its male parent. Male guillemots spend more time diving, and dive more deeply than females during this time. Chicks are capable of diving as soon as they hit the water. The female stays at the nest site for some 14 days after the chick has left.


Both male and female common murres moult after breeding and become flightless for 1–2 months. In some populations they occasionally return to the nest site throughout the winter. Adult birds reduce the time that they spend flying during the winter and are able to forage nocturnally.<ref>{{cite journal |last1=Dunn |first1=Ruth E. |last2=Wanless |first2=Sarah |last3=Daunt |first3=Francis |last4=Harris |first4=Michael P. |last5=Green |first5=Jonathan A. |title=A year in the life of a North Atlantic seabird: behavioural and energetic adjustments during the annual cycle |journal=Scientific Reports |date=7 April 2020 |volume=10 |issue=1 |page=5993 |doi=10.1038/s41598-020-62842-x|pmid=32265524 |pmc=7138806 |bibcode=2020NatSR..10.5993D |doi-access=free }}</ref> Both male and female common murres moult after breeding and become flightless for 1–2 months. Some populations have short migration distances, instead remaining close to the breeding site year-round. Such populations return to the nest site from autumn onwards. Adult birds balance their energetic budgets during the winter by reducing the time that they spend flying and are able to forage nocturnally.


==Taxonomy== ==Taxonomy==
The common murre was ] and illustrated in 1763 by the Danish bishop ] under the ] ''Colymbus aalge''.<ref>{{ cite book | last=Pontoppidan | first=Erik | author-link=Erik Pontoppidan | date=1763 | title=Den Danske Atlas eller Konge-Riget Dannemark | volume=1 | language=Danish | location=København | publisher=Printed by A.H. Godiche | page=, }}</ref> The ] is ].<ref>{{ cite book | editor-last=Peters | editor-first=James Lee | editor-link=James L. Peters | year=1934 | title=Check-List of Birds of the World | volume=2 | publisher=Harvard University Press | location=Cambridge, Massachusetts | page=352 | url=https://www.biodiversitylibrary.org/page/14483165 }}</ref> The species is now placed together with the ] in the ] '']'' that was described in 1760 by the French zoologist ].<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 C. Rasmussen | date=December 2023 | title=Noddies, gulls, terns, skimmers, skuas, auks | work=IOC World Bird List Version 14.1 | url=https://www.worldbirdnames.org/bow/gulls/ | publisher=International Ornithologists' Union | access-date=16 July 2024 }}</ref> The genus name is from ] ''ouria'', a waterbird mentioned by ]. The specific epithet ''aalge'' is an old ] word for an auk.<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=, }}</ref>

The auks are a family of ]s related to the ]s and ]s which contains several genera. The common murre is placed in the ] (murre) genus ''Uria'' (], 1760), which it shares with the ] or Brunnich's guillemot, ''U. lomvia''. These species, together with the ], ] and the ] ] make up the ] Alcini. This arrangement was originally based on analyses of auk ] and ].<ref name = strauch1985>Strauch (1985)</ref> The auks are a family of ]s related to the ]s and ]s which contains several genera. The common murre is placed in the ] (murre) genus ''Uria'' (], 1760), which it shares with the ] or Brunnich's guillemot, ''U. lomvia''. These species, together with the ], ] and the ] ] make up the ] Alcini. This arrangement was originally based on analyses of auk ] and ].<ref name = strauch1985>Strauch (1985)</ref>


The official common name for this species is Common Murre according to the IOC World Bird List, Version 11.2.<ref name=ioc/> while Common Guillemot is used in the UK,<ref>{{cite journal|author=British Ornithologists' Union|year=2013|title=The British List|url=http://www.bou.org.uk/british-list/|journal=Ibis|volume=155|pages=635–676|doi=10.1111/ibi.12069|doi-access=free}}</ref> Ireland,<ref>{{cite web |url=http://www.irbc.ie/topbar/IrishList/IRBC_IrishList(31122018).pdf |title=Irish List covering the whole of Ireland on 31st Dec 2019 |author=<!--Not stated--> |date=31 December 2019 |publisher=Irish Rare Birds Committee |access-date=15 August 2024}}</ref> and often elsewhere in Europe where English is used as a second language.<ref>see e.g. the English name column of the Finnish Bird List {{cite web |title=Suomessa havaitut luonnonvaraiset linnut |url=https://www.birdlife.fi/lintutieto/suomessa-havaitut-lintulajit/luonnonvaraiset/ |website=Yhdessä lintujen puolesta |publisher=BirdLife Suomi Finland |access-date=2024-08-15}}</ref>
The binomial name derives from ] ''ouriaa'', a waterbird mentioned by ], and ] ''aalge'', "auk" (from ] ''alka'').<ref name =BTO>{{cite web| title= Guillemot ''Uria aalge'' |work= Bird facts |url= http://blx1.bto.org/birdfacts/results/bob6340.htm |publisher=] |access-date=20 August 2008 }}</ref>


Five ] are now recognised:<ref name=ioc/>
The English "guillemot" is from French ''guillemot'', probably derived from ''Guillaume'', "William".<ref name=OED>{{Cite OED |Guillemot }}</ref> "Murre" is of uncertain origins, but may imitate the call of the common guillemot.<ref name=OED2>{{Cite OED |Murre }}</ref>
* ''U. a. aalge'' (], 1763) – coastal southeast Canada, southwest Greenland, Iceland, ], Scotland, south Norway and Baltic Sea. Includes ''intermedia'' and ''spiloptera''.<ref>{{ cite book | editor1-last=Dickinson | editor1-first=E.C. | editor1-link=Edward C. Dickinson | editor2-last=Remsen | editor2-first=J.V. Jr. | editor2-link=James Van Remsen Jr. | year=2013 | title=The Howard & Moore Complete Checklist of the Birds of the World | volume=1: Non-passerines | edition=4th | location=Eastbourne, UK | publisher=Aves Press | isbn=978-0-9568611-0-8 | page=223, Note 4 | url=https://archive.org/details/howardmoorecompl0001howa/page/223/mode/1up | url-access=registration }}</ref>
* ''U. a. hyperborea'' ], 1932 – coastal north Norway to ] and ] (northwest Russia)
* ''U. a. albionis'' ], 1923 – coastal British Isles, ] (north of Germany), northwest France and west ]
* ''U. a. inornata'' Salomonsen, 1932 – coastal ], ], Kuril and ] (east Russia), south ] (north Japan), ] (northwest of ]; formerly also ]; north Japan); ] and ] islands to west Alaska and southwest Canada
* ''U. a. californica'' (], 1861) – coastal north Washington to south California (east North Pacific)


==Etymology==
The official common name for this species is Common Murre according to the IOC World Bird List, Version 11.2.<ref>Gill, Donsker & & Rasmussen (2021)</ref> Unofficial names include common guillemot, used in the UK.<ref> https://americanornithology.org/red-eggs/ |publisher=] Retrieved 19 August 2021</ref>
The spelling ''guillemot'' is of French origin, first attested by ] in 1555, but derived from Old (11th century) French ''willelm'', and matched by English variants ''willock'' (attested 1631), ''willick'', ''will'' and ''wilkie'', all from forms of the name ], cf. {{langx|fr|Guillaume}}, but ultimately ] from the loud, high-pitched "''will'', ''willem''" begging calls of the newly fledged young of the common guillemot.<ref name="Lockwood">{{cite book|last = Lockwood| first = W. B.|title = Oxford Book of British Bird Names|publisher = Oxford University Press|year = 1984}}</ref> The American name ''murre'', also known from England (particularly Cornwall) from the 17th century, is by contrast, onomatopoeic of the growling call of adult common guillemots.<ref name="Lockwood"/><ref>: growling "murre" calls of adult, and "willem" calls of young, common guillemots, at ]</ref>


==Description== ==Description==
The common murre is {{convert|38|-|46|cm|in|0|abbr=on}} in length with a {{convert|61|-|73|cm|in|0|abbr=on}} wingspan.<ref name = mullarney1999>Mullarney et al. (1999)</ref> Male and female are indistinguishable in the field and weight ranges between {{convert|945|g|lboz|frac=2|abbr=on}} in the south of their range to {{convert|1044|g|lboz|frac=2|abbr=on}} in the north.<ref name = harris1985 >Harris & Birkhead (1985)</ref> A weight range of {{convert|775|-|1250|g|lboz|frac=2|abbr=on}} has been reported.<ref name = "CRC">''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), {{ISBN|978-0-8493-4258-5}}.</ref> In breeding plumage, the ] ''U. a. aalge'' is black on the head, back and wings, and has white underparts. It has a thin dark pointed bill and a small rounded black tail. After the ] moult, the face is white with a dark spur behind the eye, and there are often dark streaks on the flanks.<ref name = mullarney1999 /> Birds of the ] ''U. a. albionis'' are dark brown rather than black, most obviously so in colonies in southern ]. The legs and the bill are dark grey. Occasionally, adults have been seen with yellow-grey legs. In May 2008, an aberrant adult was photographed with a bright yellow bill.<ref>Blamire (2008)</ref>


The adults moult into breeding plumage in December–February, even starting as early as November in ''U. a. albionis'', and back into winter plumage soon after leaving the breeding colonies in July to August. The plumage of first winter birds is the same as the adult winter plumage. However, their moult into first summer plumage occurs later in the year than in adults. First year birds often remain in winter plumage as late as May, and their first summer plumage usually retains some white feathers around the throat.<ref name = mullarney1999 />
The common murre is {{convert|38|-|46|cm|in|0|abbr=on}} in length with a {{convert|61|-|73|cm|in|0|abbr=on}} wingspan.<ref name = mullarney1999>Mullarney et al. (1999)</ref> Male and female are indistinguishable in the field and weight ranges between {{convert|945|g|lboz|frac=2|abbr=on}} in the south of their range to {{convert|1044|g|lboz|frac=2|abbr=on}} in the north.<ref name = harris1985 >Harris & Birkhead (1985)</ref> A weight range of {{convert|775|-|1250|g|lboz|frac=2|abbr=on}} has been reported.<ref name = "CRC">''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), {{ISBN|978-0-8493-4258-5}}.</ref> In breeding plumage, the ] subspecies (''U. a. aalge'') is black on the head, back and wings, and has white underparts. It has thin dark pointed bill and a small rounded dark tail. After the ] moult, the face is white with a dark spur behind the eye. Birds of the ] ''U. a. albionis'' are dark brown rather than black, most obviously so in colonies in southern ]. Legs are grey and the bill is dark grey. Occasionally, adults are seen with yellow/grey legs. In May 2008, an aberrant adult was photographed with a bright yellow bill.<ref>Blamire (2008)</ref>


Some individuals in the North Atlantic, known as "bridled guillemots", have a white ring around the eye extending back as a white line. This is not a distinct subspecies, but a ] that becomes more common the farther north the birds breed.<ref name = hbw>Nettleship (1996)</ref>
The plumage of first winter birds is the same as the adult basic plumage. However, the first pre-alternate moult occurs later in the year. The adult pre-alternate moult is December–February, (even starting as early as November in ''U. a. albionis''). First year birds can be in basic plumage as late as May, and their alternate plumage can retain some white feathers around the throat.<ref name = mullarney1999 />


The chicks are downy with blackish feathers on top and white below. By 12 days old, contour feathers are well developed in areas except for the head. At 15 days, facial feathers show the dark eyestripe against the white throat and cheek.<ref name=mahoney1981/> They jump from the breeding cliffs at 20–21 days old, long before being fully fledged, and are cared for by the male parent at sea.<ref name = mullarney1999 />
Some individuals in the North Atlantic, known as "bridled guillemots", have a white ring around the eye extending back as a white line. This is not a distinct subspecies, but a ] that becomes more common the farther north the birds breed—perhaps ] with the northerly ], which has a white bill-stripe but no bridled morph. The white is highly contrasting especially in the latter species and would provide an easy means for an individual bird to recognize ]s in densely packed breeding colonies.<ref name = hbw>Nettleship (1996)</ref>


The common murre has a variety of calls, including a soft purring noise, but the main call of the adults, often deafening at large colonies, is a growling "murrrr"; the chicks have a food-begging call, a high-pitched whistle "willee", with considerable carrying power.
The chicks are downy with blackish feathers on top and white below. By 12 days old, contour feathers are well developed in areas except for the head. At 15 days, facial feathers show the dark eyestripe against the white throat and cheek.<ref name=mahoney1981/>
<gallery> <gallery>
Winter uria aalge.jpg|Adult in ] (winter) plumage, ] Winter uria aalge.jpg|Adult in winter ], ]
Guillemot (Uria aalge) in flight.jpg|in flight off ] Guillemot (Uria aalge) in flight.jpg|in flight off ]
Guillemot (Uria aalge) mature, on water.jpg|Bridled mature bird (white eye ring) Guillemot (Uria aalge) mature, on water.jpg|Mature 'bridled' bird (white eye ring)
</gallery> </gallery>


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==Distribution and habitat== ==Distribution and habitat==
{{outdated section|date=December 2024|reason=The publication of }}
The breeding ] is islands, rocky shores, cliffs and sea stacks.
The breeding ] is islands, rocky shores, cliffs and sea stacks. The population is large, perhaps 7.3 million breeding pairs <ref name = mitchell2004>Mitchell et al. (2004)</ref> or 18 million individuals.<ref name="iucn status 12 November 2021" /> It had been stable, but in 2016 a massive die-off of the birds in the northeast Pacific was reported. The birds seem emaciated and starving; no etiology has been found.<ref></ref> In general, potential threats include excessive hunting (legal in ]), ] and ]s. ] is home to one of the most populous colonies of nesting common murres on the North American continent.<ref>{{Cite web|url=https://oregonstateparks.org/index.cfm?do=parkPage.dsp_parkPage&parkId=131|title=Cape Meares State Scenic Viewpoint - Oregon State Parks and Recreation|website=oregonstateparks.org|access-date=2019-12-16}}</ref>


Some birds are permanent residents; northern birds ] south to open waters near ], southern California, Japan, ] and the western ]. UK populations are generally distributed near their breeding colonies year-round, but have been found to make long-distance migrations as far north as the Barents Sea.<ref name="Buckingham et al. 2022">{{cite journal |last1=Buckingham |first1=Lila |last2=Bogdanova |first2=Maria I. |last3=Green |first3=Jonathan A. |last4=Dunn |first4=Ruth E. |last5=Wanless |first5=Sarah |last6=Bennett |first6=Sophie |last7=Bevan |first7=Richard M. |last8=Call |first8=Andrew |last9=Canham |first9=Michael |last10=Corse |first10=Colin J. |last11=Harris |first11=Michael P. |last12=Heward |first12=Christopher J. |last13=Jardine |first13=David C. |last14=Lennon |first14=Jim |last15=Parnaby |first15=David |last16=Redfern |first16=Chris P. F. |last17=Scott |first17=Liz |last18=Swann |first18=Robert L. |last19=Ward |first19=Robin M. |last20=Weston |first20=Ewan D. |last21=Furness |first21=Robert W. |last22=Daunt |first22=Francis |title=Interspecific variation in non-breeding aggregation: a multi-colony tracking study of two sympatric seabirds |journal=Marine Ecology Progress Series |date=17 February 2022 |volume=684 |pages=181–197 |doi=10.3354/meps13960 |bibcode=2022MEPS..684..181B |s2cid=244752949 |doi-access=free }}</ref> Common murres rest on the water in the winter and this may have consequences for their metabolism. In the ] (which shares this winter habit) resting metabolism is 40% higher on water than it is in air.<ref name = humphreys2007>Humphreys et al. (2007)</ref>
] is home to one of the most populous colonies of nesting common murres on the North American continent.<ref>{{Cite web|url=https://oregonstateparks.org/index.cfm?do=parkPage.dsp_parkPage&parkId=131|title=Cape Meares State Scenic Viewpoint - Oregon State Parks and Recreation|website=oregonstateparks.org|access-date=2019-12-16}}</ref>


A marine heat wave killed off half the murre population in Alaska between 2014 to 2016 and as of 2024 the species has yet to recover.<ref>{{cite news |url=https://lite.cnn.com/2024/12/26/science/alaska-heat-wave-murres-global-warming/index.html |title=The bird at the center of the worst single-species mortality event in modern history isn’t recovering, scientists say |last1=Bragg |first1=Julianna |date=26 December 2024|publisher=CNN |accessdate=26 December 2024}}</ref>
{| width=98% class="wikitable"
!width=20% | Subspecies<ref name = gaston1998>Gaston & Jones (1998)</ref>
!width=35% | Range
!width=43% | Appearance
|-
| ''Uria aalge aalge''
| Nominate subspecies, eastern ], ], ], northern ] and ], southern ], possibly ] or a separate subspecies.
|
|-
| ''U. a. albionis''
| Southern ] and ], ], ], ], ]
| Smaller than nominate, chocolate brown upperparts
|-
| ''U. a. hyperborea'' ''
| Northern Norway, Northwest ], ]
| Larger than ''U. a. aalge'', black upperparts
|-
| ''U. a. intermedia''
| ]
| Intermediate between ''U. a. aalge'' and ''U. a. albionis''
|-
| ''U. a. spiloptera''
| ]
|
|-
| ''U. a. inornata''
| ], ], Eastern Russia, ]
| Largest subspecies and largest auk, slightly larger than ]
|-
| ''U. a. californica''
| ], ], ], ]
|
|-
|}


==Behaviour and ecology==
] aquarium]]
===Food and feeding===
Some birds are permanent residents; northern birds ] south to open waters near ], southern California, Japan, ] and the western ]. Common murres rest on the water in the winter and this may have consequences for their metabolism. In the ] (which shares this winter habit) resting metabolism is 40% higher on water than it is in air.<ref name = humphreys2007>Humphreys et al. (2007)</ref>

The population is large, perhaps 7.3 million breeding pairs <ref name = mitchell2004>Mitchell et al. (2004)</ref> or 18 million individuals.<ref name="iucn status 12 November 2021" /> It had been stable, but in 2016 a massive die-off of the birds in the northeast Pacific was reported. The birds seem emaciated and starving; no etiology has been found.<ref></ref> In general, potential threats include excessive hunting (legal in ]), ] and ]s.

==Ecology and behaviour==

===Feeding===
The common murre can venture far from its breeding grounds to forage; distances of {{convert|100|km|mi|-1|abbr=on}} and more are often observed<ref name = lilliendahletal2003>Lilliendahl ''et al.'' (2003)</ref> though if sufficient food is available closer by, birds only travel much shorter distances. The common murre mainly eats small ] ] {{convert|200|mm|in|0|abbr=on}} long or less, such as ], ], ]s, ]s, ]s, ] and ]. Capelin and sand lances are favourite food, but what the main prey is at any one time depends much on what is available in quantity.<ref name = lilliendahletal2003 /> It also eats some ]s, marine ]s, ], and ]s such as ]s. It consumes {{convert|20|-|32|g|oz|frac=16|abbr=on}} of food in a day on average. It is often seen carrying fish in its bill with the tail hanging out.<ref name = hbw /> The common murre can venture far from its breeding grounds to forage; distances of {{convert|100|km|mi|-1|abbr=on}} and more are often observed<ref name = lilliendahletal2003>Lilliendahl ''et al.'' (2003)</ref> though if sufficient food is available closer by, birds only travel much shorter distances. The common murre mainly eats small ] ] {{convert|200|mm|in|0|abbr=on}} long or less, such as ], ], ]s, ]s, ]s, ] and ]. Capelin and sand lances are favourite food, but what the main prey is at any one time depends much on what is available in quantity.<ref name = lilliendahletal2003 /> It also eats some ]s, marine ]s, ], and ]s such as ]s. It consumes {{convert|20|-|32|g|oz|frac=16|abbr=on}} of food in a day on average. It is often seen carrying fish in its bill with the tail hanging out.<ref name = hbw />


The ] is occasionally eaten, but it has poor nutritional value. The amount of these fish is increasing in the common murre's diet. Since 2003, the snake pipefish has increased in numbers in the North-east Atlantic and North Sea and sandeel numbers have declined.<ref name = harris2008>Harris et al. (2008)</ref> The ] is occasionally eaten, but it has poor nutritional value. The amount of these fish is increasing in the common murre's diet. Since 2003, the snake pipefish has increased in numbers in the North-east Atlantic and North Sea and sandeel numbers have declined.<ref name = harris2008>Harris et al. (2008)</ref>


===Communication=== ===Breeding===
The common murre has a variety of calls, including a soft purring noise.

===Reproduction===

====Colonies==== ====Colonies====
], ]]] ], ]]]
The common murre nests in densely packed colonies (known as "loomeries"), with up to twenty pairs occupying one square metre at peak season.{{citation needed|date=May 2013}} Common murres do not make nests and lay their eggs on bare rock ledges, under rocks, or the ground. They first breed at four to nine years old,<ref name=":0">{{Cite journal|last1=Lee|first1=Derek E.|last2=Abraham|first2=Christine L.|last3=Warzybok|first3=Peter M.|last4=Bradley|first4=Russell W.|last5=Sydeman|first5=William J.|date=2008-04-01|title=Age-Specific Survival, Breeding Success, and Recruitment in Common Murres (Uria Aalge) of the California Current System|journal=The Auk|volume=125|issue=2|pages=316–325|doi=10.1525/auk.2008.07007|s2cid=85018537|issn=0004-8038}}</ref> but most individuals recruit into the breeding population at ages six or seven,<ref name=":0" /> although birds may disperse (permanently depart their natal colony) if space is limited. Annual survival probability for birds aged 6–15 is 0.895,<ref name=":0" /> and average lifespan is about 20 years. Breeding success increases with age up to age 9–10 to 0.7 fledglings per pair, then declines in the oldest age birds, perhaps indicating ].<ref name=":0" /> The common murre nests in densely packed colonies (known as "loomeries"{{citation needed|date=August 2024}}), with up to twenty pairs occupying one square metre at peak season.{{citation needed|date=May 2013}} Common murres do not make nests and lay their eggs on bare rock ledges, under rocks, or the ground. Despite the high density of murre breeding sites, sites may vary greatly in their quality over small spatial scales. Pairs breeding at those sites of highest quality are more likely to be occupied by a breeding pairs at all population sizes, and more likely to successfully fledge a chick.<ref name="Bennett2022">{{cite journal |last1=Bennett |first1=Sophie |last2=Wanless |first2=Sarah |last3=Harris |first3=Mike P. |last4=Newell |first4=Mark A. |last5=Searle |first5=Kate R. |last6=Green |first6=Jonathan A. |last7=Daunt |first7=Francis |title=Site-dependent regulation of breeding success: Evidence for the buffer effect in the common guillemot, a colonially breeding seabird |journal=Journal of Animal Ecology |date=2022 |volume=91 |issue=4 |pages=0–14 |doi=10.1111/1365-2656.13674|pmid=35157312 |pmc=9305850 |bibcode=2022JAnEc..91..752B |s2cid=246813729 }}</ref> They first breed at four to nine years old,<ref name=":0">{{Cite journal|last1=Lee|first1=Derek E.|last2=Abraham|first2=Christine L.|last3=Warzybok|first3=Peter M.|last4=Bradley|first4=Russell W.|last5=Sydeman|first5=William J.|date=2008-04-01|title=Age-Specific Survival, Breeding Success, and Recruitment in Common Murres (Uria Aalge) of the California Current System|journal=The Auk|volume=125|issue=2|pages=316–325|doi=10.1525/auk.2008.07007|s2cid=85018537|issn=0004-8038|doi-access=free}}</ref> but most individuals recruit into the breeding population at ages six or seven,<ref name=":0" /> although birds may disperse (permanently depart their natal colony) if space is limited. Annual survival probability for birds aged 6–15 is 0.895,<ref name=":0" /> and average lifespan is about 20 years. Breeding success increases with age up to age 9–10 to 0.7 fledglings per pair, then declines in the oldest age birds, perhaps indicating ].<ref name=":0" />


High densities mean that birds are close contact with neighbouring breeders.<ref name = birkhead1978>Birkhead (1978)</ref> Common murres perform appeasement displays more often at high densities and more often than ].<ref name = birkhead1978/> ] is common both between mates and between neighbours. Allopreening helps to reduce parasites, and it may also have important social functions.<ref name = lewis2007>Lewis et al. (2007)</ref> Frequency of allopreening a neighbour correlates well with current breeding success.<ref name = lewis2007/> Allopreening may function as a stress-reducer; ledges with low levels of allopreening show increased levels of fighting and reduced breeding success.<ref name =lewis2007/> High densities mean that birds are close contact with neighbouring breeders.<ref name = birkhead1978>Birkhead (1978)</ref> Common murres perform appeasement displays more often at high densities and more often than ].<ref name = birkhead1978/> ] is common both between mates and between neighbours. Allopreening helps to reduce parasites, and it may also have important social functions.<ref name = lewis2007>Lewis et al. (2007)</ref> Frequency of allopreening a neighbour correlates well with current breeding success.<ref name = lewis2007/> Allopreening may function as a stress-reducer; ledges with low levels of allopreening show increased levels of fighting and reduced breeding success.<ref name =lewis2007/>


====Courtship==== ====Courtship====
Courtship displays including bowing, billing and mutual preening. The male points its head vertically and makes croaking and growling noises to attract the females. The species is ], but pairs may split if breeding is unsuccessful.<ref name = kokko2004>Kokko et al. (2004)</ref><ref name = moody2005>Moody et al. (2005)</ref> Courtship displays including bowing, billing and mutual preening. The male points its head vertically and makes croaking and growling noises to attract the females. The species is ], but pairs may split if breeding is unsuccessful.<ref name = kokko2004>Kokko et al. (2004)</ref><ref name = moody2005>Moody et al. (2005)</ref>


====Eggs and incubation==== ====Eggs and incubation====
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] ]


Common murre eggs are large (around 11% of female weight<ref name=gaston1998/>), and are pointed at one end. The egg's ] shape is popularly ascribed the function of allowing the egg to spin on its axis or in an arc when disturbed, however there is no evidence to support this claim.<ref name="pyriformegg">{{cite journal |last1=Birkhead |first1=Tim R. |last2=Thompson |first2=Jamie E. |last3=Montgomerie |first3=Robert |title=The pyriform egg of the Common Murre (Uria aalge) is more stable on sloping surfacesEl huevo piriforme de Uria aalge es más estable en superficies inclinadasCommon Murre egg shape and stability |journal=The Auk |date=1 October 2018 |volume=135 |issue=4 |pages=1020–1032 |doi=10.1642/AUK-18-38.1 |language=en|doi-access=free }}</ref> Various hypotheses have arisen to explain the egg's shape: Common murre eggs are large (around 11% of female weight<ref name = gaston1998>Gaston & Jones (1998)</ref>), and are pointed at one end. The egg's ] shape is popularly ascribed the function of allowing the egg to spin on its axis or in an arc when disturbed, however there is no evidence to support this claim.<ref name="pyriformegg">{{cite journal |last1=Birkhead |first1=Tim R. |last2=Thompson |first2=Jamie E. |last3=Montgomerie |first3=Robert |title=The pyriform egg of the Common Murre (Uria aalge) is more stable on sloping surfacesEl huevo piriforme de Uria aalge es más estable en superficies inclinadasCommon Murre egg shape and stability |journal=The Auk |date=1 October 2018 |volume=135 |issue=4 |pages=1020–1032 |doi=10.1642/AUK-18-38.1 |language=en|doi-access=free }}</ref> Various hypotheses have arisen to explain the egg's shape:
# Pyriform eggs are more stable on a sloping surface than more elliptical eggs, such as that of the ].<ref name="pyriformegg"></ref> # Pyriform eggs are more stable on a sloping surface than more elliptical eggs, such as that of the ].<ref name="pyriformegg" />
# The shape allows efficient heat transfer during incubation.<ref name=johnson1941>Johnson (1941)</ref> # The shape allows efficient heat transfer during incubation.<ref name=johnson1941>Johnson (1941)</ref>
# As a compromise between large egg size and small cross-section. Large size allows quick development of the chick. Small cross-sectional area allows the adult bird to have a small cross-section and therefore reduce drag when swimming.<ref name=gaston1998/> # As a compromise between large egg size and small cross-section. Large size allows quick development of the chick. Small cross-sectional area allows the adult bird to have a small cross-section and therefore reduce drag when swimming.<ref name=gaston1998/>
# Due to its pyriform shape, a higher proportion of the eggshell is in contact with the cliff minimising the effects of impact by neighbouring birds. # Due to its pyriform shape, a higher proportion of the eggshell is in contact with the cliff minimising the effects of impact by neighbouring birds.
# It helps to confine faecal contamination to the pointy end of the egg. The blunt end, where the embryo's head and air cell are located, is kept relatively free of debris, allowing gases to pass through the shell unimpeded;.<ref>{{cite journal |author1=Birkhead, T. R. |author2=Thompson, J. E. | author3=Jackson, D. |author4=Biggins, J. D. | year=2017| title=The point of a Guillemot's egg| journal=Ibis| volume=159| pages=255–265| doi=10.1111/ibi.12458 | issue=2| url=http://eprints.whiterose.ac.uk/113128/16/Birkhead%20et%20al.%202017%20IBIS%20accepted%20manuscript.pdf| doi-access=free}}</ref><ref name="pyriformegg"></ref> # It helps to confine faecal contamination to the pointy end of the egg. The blunt end, where the embryo's head and air cell are located, is kept relatively free of debris, allowing gases to pass through the shell unimpeded;.<ref>{{cite journal |author1=Birkhead, T. R. |author2=Thompson, J. E. | author3=Jackson, D. |author4=Biggins, J. D. | year=2017| title=The point of a Guillemot's egg| journal=Ibis| volume=159| pages=255–265| doi=10.1111/ibi.12458 | issue=2| url=http://eprints.whiterose.ac.uk/113128/16/Birkhead%20et%20al.%202017%20IBIS%20accepted%20manuscript.pdf| doi-access=free}}</ref><ref name="pyriformegg" />


Eggs are laid between May and July for the Atlantic populations and March to July for those in the Pacific. The female spends less time ashore during the two weeks before laying. When laying, she assumes a "phoenix-like" posture: her body raised upright on vertical ]; wings half outstretched. The egg emerges point first and laying usually takes 5–10 minutes.<ref name=harris2006>Harris & Wanless (2006)</ref> Eggs are laid between May and July for the Atlantic populations and March to July for those in the Pacific. The female spends less time ashore during the two weeks before laying. When laying, she assumes a "phoenix-like" posture: her body raised upright on vertical ]; wings half outstretched. The egg emerges point first and laying usually takes 5–10 minutes.<ref name=harris2006>Harris & Wanless (2006)</ref>
] steals an egg, ]]] ] steals an egg, ]]]


The eggs vary in colour and pattern to help the parents recognize them, each egg's pattern being unique.<ref>{{cite book |last1=Birkhead |first1=Tim |title=The Most Perfect Thing: Inside (and Outside) a Bird's Egg |date=2016 |publisher=Bloomsbury |location=London |page=117}}</ref> Colours include white, green, blue or brown with spots or speckles in black or lilac. After laying, the female will look at the egg before starting the first incubation shift.<ref name=harris2006/> Both parents incubate the egg using a single, centrally located ] for the 28 to 34 days to hatching in shifts of 1–38 hours.<ref name=gaston1998/> The eggs vary in colour and pattern to help the parents recognize them, each egg's pattern being unique.<ref>{{cite book |last1=Birkhead |first1=Tim |title=The Most Perfect Thing: Inside (and Outside) a Bird's Egg |date=2016 |publisher=Bloomsbury |location=London |page=117}}</ref> Colours include white, green, blue or brown with spots or speckles in black or lilac. After laying, the female will look at the egg before starting the first incubation shift.<ref name=harris2006/> Both parents incubate the egg using a single, centrally located ] for the 28 to 34 days to hatching in shifts of 1–38 hours.<ref name=gaston1998/>


Eggs can be lost due to predation or carelessness. ] and ]s are opportunist egg thieves. Eggs are also knocked from ledges during fights. If the first egg is lost, the female may lay a second egg. This egg is usually lighter than the first, with a lighter yolk.{{citation needed|date=May 2013}} Chicks from second eggs grow quicker than those from first eggs. However this rapid growth comes at a cost, first chicks have larger fat reserves and can withstand temporary shortages of food.{{Citation needed|date=January 2012}} Eggs can be lost due to predation or carelessness. ] and ]s are opportunist egg thieves. Eggs are also knocked from ledges during fights. If the first egg is lost, the female may lay a second egg. This egg is usually lighter than the first, with a lighter yolk.{{citation needed|date=May 2013}} Chicks from second eggs grow quicker than those from first eggs. However this rapid growth comes at a cost, first chicks have larger fat reserves and can withstand temporary shortages of food.{{Citation needed|date=January 2012}}
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The chicks will leave the nest after 16 to 30 days (average 20–22 days),<ref name = harris1985/> and glide down into the sea, slowing their fall by fluttering as they are not yet able to fly. Chicks glide from heights as high as {{convert|457|m|ft|abbr=on}} to the water below.{{citation needed|date=September 2014}} Once the young chick has left the nest, the male is in close attendance for up to two months. The chicks are able to fly roughly two weeks after fledging. Up until then the male feeds and cares for the chick at sea. In its migration south the chick swims about {{convert|1000|km|mi|sigfig=1|abbr=on}}. The female remains at the nest site for up to 36 days after the chick has fledged (average 16 days).<ref name = harris2003>Harris & Wanless (2003)</ref> The chicks will leave the nest after 16 to 30 days (average 20–22 days),<ref name = harris1985/> and glide down into the sea, slowing their fall by fluttering as they are not yet able to fly. Chicks glide from heights as high as {{convert|457|m|ft|abbr=on}} to the water below.{{citation needed|date=September 2014}} Once the young chick has left the nest, the male is in close attendance for up to two months. The chicks are able to fly roughly two weeks after fledging. Up until then the male feeds and cares for the chick at sea. In its migration south the chick swims about {{convert|1000|km|mi|sigfig=1|abbr=on}}. The female remains at the nest site for up to 36 days after the chick has fledged (average 16 days).<ref name = harris2003>Harris & Wanless (2003)</ref>


==Relationship to humans== ==Relationship with humans==
{{multiple image {{multiple image
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* {{cite journal|author1=Harding, Ann M.A. |author2=Piatt, John F. |author3=Schmutz, Joel A. |year=2007|title=Seabird behavior as an indicator of food supplies: sensitivity across the breeding season|journal=Marine Ecology Progress Series|volume=352|pages= 269–274|doi=10.3354/meps07072|bibcode=2007MEPS..352..269H |doi-access=free}} * {{cite journal|author1=Harding, Ann M.A. |author2=Piatt, John F. |author3=Schmutz, Joel A. |year=2007|title=Seabird behavior as an indicator of food supplies: sensitivity across the breeding season|journal=Marine Ecology Progress Series|volume=352|pages= 269–274|doi=10.3354/meps07072|bibcode=2007MEPS..352..269H |doi-access=free}}
* Harris, Michael P. & Birkhead, Tim R. (1985): ''Breeding Ecology of the Atlantic Alcidae'' in Nettleship & Birkhead (1985) pp 155–204 * Harris, Michael P. & Birkhead, Tim R. (1985): ''Breeding Ecology of the Atlantic Alcidae'' in Nettleship & Birkhead (1985) pp 155–204
* {{cite journal|author1=Harris, Michael P. |author2=Bull, J. |author3=Wanless, Sarah |year=2000|url=http://www.seabirdgroup.org.uk/?page=journalcontents&vol=2&no=2 |title=Common Guillemots ''Uria aalge'' successfully feed two chicks|journal= Atlantic Seabirds |volume=2|issue=2|pages=92–94}} * {{cite journal|author1=Harris, Michael P.|author2=Bull, J.|author3=Wanless, Sarah|year=2000|url=http://www.seabirdgroup.org.uk/?page=journalcontents&vol=2&no=2|title=Common Guillemots ''Uria aalge'' successfully feed two chicks|journal=Atlantic Seabirds|volume=2|issue=2|pages=92–94}}
* {{cite journal|author1=Harris, Michael P. |author2=Frederiksen, Morten |author3=Wanless, Sarah |doi=10.1111/j.1474-919X.2007.00667.x|title=Within- and between-year variation in the juvenile survival of the Common Guillemot ''Uria aalge''|year=2007|journal=Ibis|volume=149|issue=3|pages=472}} * {{cite journal|author1=Harris, Michael P. |author2=Frederiksen, Morten |author3=Wanless, Sarah |doi=10.1111/j.1474-919X.2007.00667.x|title=Within- and between-year variation in the juvenile survival of the Common Guillemot ''Uria aalge''|year=2007|journal=Ibis|volume=149|issue=3|pages=472}}
* {{cite journal|author1=Harris, Michael P. |author2=Newell, Mark |author3=Daunt, Francis |author4=Speakman, John R. |author5=Wanless, Sarah |doi=10.1111/j.1474-919X.2007.00780.x|title=Snake Pipefish ''Entelurus aequoreus'' are poor food for seabirds|year=2007|journal=Ibis|volume=150|issue=2|pages=413}} * {{cite journal|author1=Harris, Michael P. |author2=Newell, Mark |author3=Daunt, Francis |author4=Speakman, John R. |author5=Wanless, Sarah |doi=10.1111/j.1474-919X.2007.00780.x|title=Snake Pipefish ''Entelurus aequoreus'' are poor food for seabirds|year=2007|journal=Ibis|volume=150|issue=2|pages=413}}
* {{cite journal|author1=Harris, Michael P. |author2=Wanless, Sarah |doi=10.1642/0004-8038(2003)1202.0.CO;2|title=Postfledging occupancy of breeding sites by female common murres (''Uria aalge'')|year=2003|volume=120|pages=75|journal=The Auk}} * {{cite journal|author1=Harris, Michael P. |author2=Wanless, Sarah |doi=10.1642/0004-8038(2003)1202.0.CO;2|title=Postfledging occupancy of breeding sites by female common murres (''Uria aalge'')|year=2003|volume=120|pages=75|journal=The Auk|s2cid=86711711 }}
* {{cite journal|author1=Harris, Michael P. |author2=Wanless, Sarah |year=2006|title=Laying a big e.g. on a little ledge:does it help a female Common Guillemot if Dad's there?|journal=]|volume=99|pages= 230–235}} * {{cite journal|author1=Harris, Michael P. |author2=Wanless, Sarah |year=2006|title=Laying a big e.g. on a little ledge:does it help a female Common Guillemot if Dad's there?|journal=]|volume=99|pages= 230–235}}
* Harrison, Paul (2008): ''Lundy (Climbers Club Guides)'' Climbers Club * Harrison, Paul (2008): ''Lundy (Climbers Club Guides)'' Climbers Club
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* {{cite journal|author1=Humphreys, Elizabeth M. |author2=Wanless, Sarah |author3=Bryant, David M. |year=2007|title=Elevated metabolic costs while resting on water in a surface feeder: the Black-legged Kittiwake ''Rissa tridactyla''|journal=]|volume=149|pages=106–111|doi=10.1111/j.1474-919X.2006.00618.x}} * {{cite journal|author1=Humphreys, Elizabeth M. |author2=Wanless, Sarah |author3=Bryant, David M. |year=2007|title=Elevated metabolic costs while resting on water in a surface feeder: the Black-legged Kittiwake ''Rissa tridactyla''|journal=]|volume=149|pages=106–111|doi=10.1111/j.1474-919X.2006.00618.x}}
* {{cite journal|author=Johnson, Robert A. |year=1941|title=Nesting behavior of the Atlantic Murre|journal=]|volume=58|issue=2|pages= 153–163|doi=10.2307/4079099|jstor=4079099}} * {{cite journal|author=Johnson, Robert A. |year=1941|title=Nesting behavior of the Atlantic Murre|journal=]|volume=58|issue=2|pages= 153–163|doi=10.2307/4079099|jstor=4079099}}
* {{cite journal|author1=Kokko, H. |author2=Harris, Michael, P. |author3=Wanless, Sarah |doi=10.1111/j.0021-8790.2004.00813.x|title=Competition for breeding sites and site-dependent population regulation in a highly colonial seabird, the common guillemot ''Uria aalge''|year=2004|journal=Journal of Animal Ecology|volume=73|issue=2|pages=367}} * {{cite journal|author1=Kokko, H. |author2=Harris, Michael, P. |author3=Wanless, Sarah |doi=10.1111/j.0021-8790.2004.00813.x|title=Competition for breeding sites and site-dependent population regulation in a highly colonial seabird, the common guillemot ''Uria aalge''|year=2004|journal=Journal of Animal Ecology|volume=73|issue=2|pages=367|doi-access=free|bibcode=2004JAnEc..73..367K }}
* {{cite journal|author1=Lewis, Sue |author2=Roberts, Gilbert |author3=Harris, Michael P. |author4=Prigmore, Carina |author5=Wanless, Sarah |year=2007|title=Fitness increases with partner and neighbour allopreening|journal=Biology Letters|volume=3|pages=386–389|doi=10.1098/rsbl.2007.0258|pmid=17550875|issue=4|pmc=2390679}} * {{cite journal|author1=Lewis, Sue |author2=Roberts, Gilbert |author3=Harris, Michael P. |author4=Prigmore, Carina |author5=Wanless, Sarah |year=2007|title=Fitness increases with partner and neighbour allopreening|journal=Biology Letters|volume=3|pages=386–389|doi=10.1098/rsbl.2007.0258|pmid=17550875|issue=4|pmc=2390679}}
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* {{cite journal|last=Vaughn | first=H.R.H. | year=1937 | title=Flight speed of guillemots, razorbills and puffins | journal=British Birds | volume=31 | page= 123 | url=https://britishbirds.co.uk/wp-content/uploads/article_files/V31/V31_N04/V31_N04_P120_126_N021.pdf }} * {{cite journal | last=Vaughn | first=H.R.H. | year=1937 | title=Flight speed of guillemots, razorbills and puffins | journal=British Birds | volume=31 | page=123 | url=https://britishbirds.co.uk/wp-content/uploads/article_files/V31/V31_N04/V31_N04_P120_126_N021.pdf | access-date=2015-11-08 | archive-date=2016-03-05 | archive-url=https://web.archive.org/web/20160305134516/https://britishbirds.co.uk/wp-content/uploads/article_files/V31/V31_N04/V31_N04_P120_126_N021.pdf | url-status=dead }}
* {{cite journal|author=Votier, S.C.|author2=Birkhead, T.R.|author3=Oro, D.|author4=Trinder, M.|author5=Grantham, M.J.|author6=Clark, J.A.|author7=McCleery, R.H.|author8=Hatchwell, B.J.|name-list-style=amp |year=2008|doi=10.1111/j.1365-2656.2008.01421.x|title=Recruitment and survival of immature seabirds in relation to oil spills and climate variability|journal=Journal of Animal Ecology|volume=77|issue=5|pages=974–983|pmid=18624739|doi-access=free}} * {{cite journal|author=Votier, S.C.|author2=Birkhead, T.R.|author3=Oro, D.|author4=Trinder, M.|author5=Grantham, M.J.|author6=Clark, J.A.|author7=McCleery, R.H.|author8=Hatchwell, B.J.|name-list-style=amp |year=2008|doi=10.1111/j.1365-2656.2008.01421.x|title=Recruitment and survival of immature seabirds in relation to oil spills and climate variability|journal=Journal of Animal Ecology|volume=77|issue=5|pages=974–983|pmid=18624739|doi-access=|bibcode=2008JAnEc..77..974V }}
* {{cite journal|author1=Wanless, S. |author2=Harris, M.P. |author3=Redman, P. |author4=Speakman, J.R. |year=2005|title=Low energy values of fish as a probable cause of a major seabird breeding failure in the North Sea|journal= Marine Ecology Progress Series |volume=294|pages= 1–8|doi=10.3354/meps294001|bibcode=2005MEPS..294....1W |doi-access=free}} * {{cite journal|author1=Wanless, S. |author2=Harris, M.P. |author3=Redman, P. |author4=Speakman, J.R. |year=2005|title=Low energy values of fish as a probable cause of a major seabird breeding failure in the North Sea|journal= Marine Ecology Progress Series |volume=294|pages= 1–8|doi=10.3354/meps294001|bibcode=2005MEPS..294....1W |doi-access=free}}
* White, Peter; (1995), ''The Farallon Islands, Sentinels of the Golden Gate'', Scottwall Associates:San Francisco, {{ISBN|0-942087-10-0}} * White, Peter; (1995), ''The Farallon Islands, Sentinels of the Golden Gate'', Scottwall Associates:San Francisco, {{ISBN|0-942087-10-0}}
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Latest revision as of 23:12, 26 December 2024

Species of bird

Common murre
Bird calls recorded in Pembrokeshire, Wales
Conservation status

Least Concern  (IUCN 3.1)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Charadriiformes
Family: Alcidae
Genus: Uria
Species: U. aalge
Binomial name
Uria aalge
(Pontoppidan, 1763)
Synonyms
  • Colymbus aalge Pontoppidan, 1763
  • Colymbus troile Linnaeus, 1766
  • Uria troile Linnaeus

The common murre or common guillemot (Uria aalge) is a large auk. It has a circumpolar distribution, occurring in low-Arctic and boreal waters in the North Atlantic and North Pacific. It spends most of its time at sea, only coming to land to breed on rocky cliff shores or islands.

Common murres are fast in direct flight but are not very agile. They are highly mobile underwater using their wings to 'fly' through the water column, where they typically dive to depths of 30–60 m (100–195 ft). Depths of up to 180 m (590 ft) have been recorded.

Common murres breed in colonies at high densities. Nesting pairs may be in bodily contact with their neighbours. They make no nest; their single egg is incubated between the adult's feet on a bare rock ledge on a cliff face. Eggs hatch after ~30 days incubation. The chick is born downy and can regulate its body temperature after 10 days. Some 20 days after hatching the chick leaves its nesting ledge and heads for the sea, unable to fly, but gliding for some distance with fluttering wings, accompanied by its male parent. Male guillemots spend more time diving, and dive more deeply than females during this time. Chicks are capable of diving as soon as they hit the water. The female stays at the nest site for some 14 days after the chick has left.

Both male and female common murres moult after breeding and become flightless for 1–2 months. Some populations have short migration distances, instead remaining close to the breeding site year-round. Such populations return to the nest site from autumn onwards. Adult birds balance their energetic budgets during the winter by reducing the time that they spend flying and are able to forage nocturnally.

Taxonomy

The common murre was formally described and illustrated in 1763 by the Danish bishop Erik Pontoppidan under the binomial name Colymbus aalge. The type locality is Iceland. The species is now placed together with the thick-billed murre in the genus Uria that was described in 1760 by the French zoologist Mathurin Jacques Brisson. The genus name is from Ancient Greek ouria, a waterbird mentioned by Athenaeus. The specific epithet aalge is an old Danish word for an auk.

The auks are a family of seabirds related to the gulls and terns which contains several genera. The common murre is placed in the guillemot (murre) genus Uria (Brisson, 1760), which it shares with the thick-billed murre or Brunnich's guillemot, U. lomvia. These species, together with the razorbill, little auk and the extinct great auk make up the tribe Alcini. This arrangement was originally based on analyses of auk morphology and ecology.

The official common name for this species is Common Murre according to the IOC World Bird List, Version 11.2. while Common Guillemot is used in the UK, Ireland, and often elsewhere in Europe where English is used as a second language.

Five subspecies are now recognised:

Etymology

The spelling guillemot is of French origin, first attested by Pierre Belon in 1555, but derived from Old (11th century) French willelm, and matched by English variants willock (attested 1631), willick, will and wilkie, all from forms of the name William, cf. French: Guillaume, but ultimately onomatopoeic from the loud, high-pitched "will, willem" begging calls of the newly fledged young of the common guillemot. The American name murre, also known from England (particularly Cornwall) from the 17th century, is by contrast, onomatopoeic of the growling call of adult common guillemots.

Description

The common murre is 38–46 cm (15–18 in) in length with a 61–73 cm (24–29 in) wingspan. Male and female are indistinguishable in the field and weight ranges between 945 g (2 lb 1+1⁄2 oz) in the south of their range to 1,044 g (2 lb 5 oz) in the north. A weight range of 775–1,250 g (1 lb 11+1⁄2 oz – 2 lb 12 oz) has been reported. In breeding plumage, the nominate subspecies U. a. aalge is black on the head, back and wings, and has white underparts. It has a thin dark pointed bill and a small rounded black tail. After the post-breeding moult, the face is white with a dark spur behind the eye, and there are often dark streaks on the flanks. Birds of the subspecies U. a. albionis are dark brown rather than black, most obviously so in colonies in southern Britain. The legs and the bill are dark grey. Occasionally, adults have been seen with yellow-grey legs. In May 2008, an aberrant adult was photographed with a bright yellow bill.

The adults moult into breeding plumage in December–February, even starting as early as November in U. a. albionis, and back into winter plumage soon after leaving the breeding colonies in July to August. The plumage of first winter birds is the same as the adult winter plumage. However, their moult into first summer plumage occurs later in the year than in adults. First year birds often remain in winter plumage as late as May, and their first summer plumage usually retains some white feathers around the throat.

Some individuals in the North Atlantic, known as "bridled guillemots", have a white ring around the eye extending back as a white line. This is not a distinct subspecies, but a polymorphism that becomes more common the farther north the birds breed.

The chicks are downy with blackish feathers on top and white below. By 12 days old, contour feathers are well developed in areas except for the head. At 15 days, facial feathers show the dark eyestripe against the white throat and cheek. They jump from the breeding cliffs at 20–21 days old, long before being fully fledged, and are cared for by the male parent at sea.

The common murre has a variety of calls, including a soft purring noise, but the main call of the adults, often deafening at large colonies, is a growling "murrrr"; the chicks have a food-begging call, a high-pitched whistle "willee", with considerable carrying power.

Flight

The common murre flies with fast wing beats and has a flight speed of 80 km/h (50 mph). Groups of birds are often seen flying together in a line just above the sea surface. However, a high wing loading of 2 g/cm means that this species is not very agile and take-off is difficult. Common murres become flightless for 45–60 days while moulting their primary feathers. The sound of the wing beats of the murres are often described as similar to a helicopter.

Diving

Skeleton

The common murre is a pursuit-diver that forages for food by swimming underwater using its wings for propulsion. Dives usually last less than one minute, but the bird swims underwater for distances of over 30 m (100 ft) on a regular basis. Diving depths up to 180 m (590 ft) have been recorded and birds can remain underwater for a couple of minutes.

Distribution and habitat

This section needs to be updated. The reason given is: The publication of a study about the 2014–16 die-off. Please help update this article to reflect recent events or newly available information. (December 2024)

The breeding habitat is islands, rocky shores, cliffs and sea stacks. The population is large, perhaps 7.3 million breeding pairs or 18 million individuals. It had been stable, but in 2016 a massive die-off of the birds in the northeast Pacific was reported. The birds seem emaciated and starving; no etiology has been found. In general, potential threats include excessive hunting (legal in Newfoundland), pollution and oil spills. Cape Meares, Oregon is home to one of the most populous colonies of nesting common murres on the North American continent.

Some birds are permanent residents; northern birds migrate south to open waters near New England, southern California, Japan, Korea and the western Mediterranean. UK populations are generally distributed near their breeding colonies year-round, but have been found to make long-distance migrations as far north as the Barents Sea. Common murres rest on the water in the winter and this may have consequences for their metabolism. In the black-legged kittiwake (which shares this winter habit) resting metabolism is 40% higher on water than it is in air.

A marine heat wave killed off half the murre population in Alaska between 2014 to 2016 and as of 2024 the species has yet to recover.

Behaviour and ecology

Food and feeding

The common murre can venture far from its breeding grounds to forage; distances of 100 km (60 mi) and more are often observed though if sufficient food is available closer by, birds only travel much shorter distances. The common murre mainly eats small schooling forage fish 200 mm (8 in) long or less, such as polar cod, capelin, sand lances, sprats, sandeels, Atlantic cod and Atlantic herring. Capelin and sand lances are favourite food, but what the main prey is at any one time depends much on what is available in quantity. It also eats some molluscs, marine worms, squid, and crustaceans such as amphipods. It consumes 20–32 g (11⁄16–1+1⁄8 oz) of food in a day on average. It is often seen carrying fish in its bill with the tail hanging out.

The snake pipefish is occasionally eaten, but it has poor nutritional value. The amount of these fish is increasing in the common murre's diet. Since 2003, the snake pipefish has increased in numbers in the North-east Atlantic and North Sea and sandeel numbers have declined.

Breeding

Colonies

Part of a U. a. californica colony, Farallon Islands, California

The common murre nests in densely packed colonies (known as "loomeries"), with up to twenty pairs occupying one square metre at peak season. Common murres do not make nests and lay their eggs on bare rock ledges, under rocks, or the ground. Despite the high density of murre breeding sites, sites may vary greatly in their quality over small spatial scales. Pairs breeding at those sites of highest quality are more likely to be occupied by a breeding pairs at all population sizes, and more likely to successfully fledge a chick. They first breed at four to nine years old, but most individuals recruit into the breeding population at ages six or seven, although birds may disperse (permanently depart their natal colony) if space is limited. Annual survival probability for birds aged 6–15 is 0.895, and average lifespan is about 20 years. Breeding success increases with age up to age 9–10 to 0.7 fledglings per pair, then declines in the oldest age birds, perhaps indicating reproductive senescence.

High densities mean that birds are close contact with neighbouring breeders. Common murres perform appeasement displays more often at high densities and more often than razorbills. Allopreening is common both between mates and between neighbours. Allopreening helps to reduce parasites, and it may also have important social functions. Frequency of allopreening a neighbour correlates well with current breeding success. Allopreening may function as a stress-reducer; ledges with low levels of allopreening show increased levels of fighting and reduced breeding success.

Courtship

Courtship displays including bowing, billing and mutual preening. The male points its head vertically and makes croaking and growling noises to attract the females. The species is monogamous, but pairs may split if breeding is unsuccessful.

Eggs and incubation

See also: Bird egg
Murre eggs

Common murre eggs are large (around 11% of female weight), and are pointed at one end. The egg's pyriform shape is popularly ascribed the function of allowing the egg to spin on its axis or in an arc when disturbed, however there is no evidence to support this claim. Various hypotheses have arisen to explain the egg's shape:

  1. Pyriform eggs are more stable on a sloping surface than more elliptical eggs, such as that of the razorbill.
  2. The shape allows efficient heat transfer during incubation.
  3. As a compromise between large egg size and small cross-section. Large size allows quick development of the chick. Small cross-sectional area allows the adult bird to have a small cross-section and therefore reduce drag when swimming.
  4. Due to its pyriform shape, a higher proportion of the eggshell is in contact with the cliff minimising the effects of impact by neighbouring birds.
  5. It helps to confine faecal contamination to the pointy end of the egg. The blunt end, where the embryo's head and air cell are located, is kept relatively free of debris, allowing gases to pass through the shell unimpeded;.

Eggs are laid between May and July for the Atlantic populations and March to July for those in the Pacific. The female spends less time ashore during the two weeks before laying. When laying, she assumes a "phoenix-like" posture: her body raised upright on vertical tarsi; wings half outstretched. The egg emerges point first and laying usually takes 5–10 minutes.

Herring gull steals an egg, Lundy

The eggs vary in colour and pattern to help the parents recognize them, each egg's pattern being unique. Colours include white, green, blue or brown with spots or speckles in black or lilac. After laying, the female will look at the egg before starting the first incubation shift. Both parents incubate the egg using a single, centrally located brood patch for the 28 to 34 days to hatching in shifts of 1–38 hours.

Eggs can be lost due to predation or carelessness. Crows and gulls are opportunist egg thieves. Eggs are also knocked from ledges during fights. If the first egg is lost, the female may lay a second egg. This egg is usually lighter than the first, with a lighter yolk. Chicks from second eggs grow quicker than those from first eggs. However this rapid growth comes at a cost, first chicks have larger fat reserves and can withstand temporary shortages of food.

Growth of the chick

Chicks occupy an intermediate position between the precocial chicks of genus Synthliboramphus and the semi-precocial chicks of the Atlantic puffin. They are born downy and by 10 days old they are able to regulate their own temperature. Except in times of food shortage there is at least one parent present at all times, and both parents are present 10–30% of the time. Both parents alternate between brooding the chick or foraging for food.

Adults feeding chick, Lundy

Provisioning is usually divided equally between each parent, but unequal provisioning effort can lead to divorce. Common murres are single-prey loaders, this means that they carry one fish at time. The fish is held lengthways in the adult's bill, with the fish's tail hanging from the end of the beak. The returning adult will form its wings into a 'tent' to protect the chick. The adult points its head downwards and the chick swallows the fish head first.

Alloparenting behaviour is frequently observed. Non-breeding and failed breeders show great interest in other chicks, and will attempt to brood or feed them. This activity is more common as the chicks get older and begin to explore their ledge. There has also been a record of a pair managing to raise two chicks. Adults that have lost chicks or eggs will sometimes bring fish to the nest site and try to feed their imaginary chick.

At time of extreme food stress, the social activity of the breeding ledge can break down. On the Isle of May colony in 2007, food availability was low. Adults spent more of their time-budget foraging for their chicks and had to leave them unattended at times. Unattended chicks were attacked by breeding neighbour which often led to their deaths. Non-breeding and failed breeders continued to show alloparental care.

Chick, Alaska

The chicks will leave the nest after 16 to 30 days (average 20–22 days), and glide down into the sea, slowing their fall by fluttering as they are not yet able to fly. Chicks glide from heights as high as 457 m (1,499 ft) to the water below. Once the young chick has left the nest, the male is in close attendance for up to two months. The chicks are able to fly roughly two weeks after fledging. Up until then the male feeds and cares for the chick at sea. In its migration south the chick swims about 1,000 km (600 mi). The female remains at the nest site for up to 36 days after the chick has fledged (average 16 days).

Relationship with humans

Common murre chick, LundyBreeding plumageCommon murre family

Pollution

Major oil spills double the winter mortality of breeding adults but appear to have little effect on birds less than three years old. This loss of breeding birds can be compensated by increased recruitment of 4–6 year olds to breeding colonies.

Recreational disturbance

Nesting common murres are prone to two main sources of recreational disturbance: rock-climbing and birdwatching. Sea cliffs are a paradise for climbers as well as birds; a small island like Lundy has over 1000 described climbing routes. To minimise disturbance, some cliffs are subject to seasonal climbing bans.

Birdwatching has conflicting effects on common murres. Birdwatchers petitioned the UK government to introduce the Sea Birds Preservation Act 1869. This act was designed to reduce the effects of shooting and egg collecting during the breeding season. Current concerns include managing the effect of visitor numbers at wildlife reserves. Common murres have been shown to be sensitive to visitor numbers.

Seabirds as indicators of marine health

When common murres are feeding their young, they return with one fish at a time. The provisioning time relates to the distance of the feeding areas from the colony and the numbers of available fish. There is a strong non-linear relationship between fish density and colony attendance during chick-rearing.

As a food source

In areas such as Newfoundland and Labrador, the birds, along with the related thick-billed murre, are referred to as 'turrs' or 'tuirs', and are consumed. The meat is dark and quite oily, due to the birds' diet of fish. Eggs have also been harvested. Eggers from San Francisco took almost half a million eggs a year from the Farallon Islands in the mid-19th century to feed the growing city.

Notes

  1. ^ BirdLife International (2018). "Uria aalge". IUCN Red List of Threatened Species. 2018: e.T22694841A132577296. doi:10.2305/IUCN.UK.2018-2.RLTS.T22694841A132577296.en. Retrieved 12 November 2021.
  2. "Uria aalge: Guillemot". National Biodiversity Network (NBN) Atlas. Retrieved 2020-01-31.
  3. Pontoppidan, Erik (1763). Den Danske Atlas eller Konge-Riget Dannemark (in Danish). Vol. 1. København : Printed by A.H. Godiche. p. 621, Plate 26.
  4. Peters, James Lee, ed. (1934). Check-List of Birds of the World. Vol. 2. Cambridge, Massachusetts: Harvard University Press. p. 352.
  5. ^ Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (December 2023). "Noddies, gulls, terns, skimmers, skuas, auks". IOC World Bird List Version 14.1. International Ornithologists' Union. Retrieved 16 July 2024.
  6. Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. pp. 229, 29. ISBN 978-1-4081-2501-4.
  7. Strauch (1985)
  8. British Ornithologists' Union (2013). "The British List". Ibis. 155: 635–676. doi:10.1111/ibi.12069.
  9. "Irish List covering the whole of Ireland on 31st Dec 2019" (PDF). Irish Rare Birds Committee. 31 December 2019. Retrieved 15 August 2024.
  10. see e.g. the English name column of the Finnish Bird List "Suomessa havaitut luonnonvaraiset linnut". Yhdessä lintujen puolesta. BirdLife Suomi Finland. Retrieved 2024-08-15.
  11. Dickinson, E.C.; Remsen, J.V. Jr., eds. (2013). The Howard & Moore Complete Checklist of the Birds of the World. Vol. 1: Non-passerines (4th ed.). Eastbourne, UK: Aves Press. p. 223, Note 4. ISBN 978-0-9568611-0-8.
  12. ^ Lockwood, W. B. (1984). Oxford Book of British Bird Names. Oxford University Press.
  13. External audio: growling "murre" calls of adult, and "willem" calls of young, common guillemots, at xeno-canto
  14. ^ Mullarney et al. (1999)
  15. ^ Harris & Birkhead (1985)
  16. CRC Handbook of Avian Body Masses by John B. Dunning Jr. (Editor). CRC Press (1992), ISBN 978-0-8493-4258-5.
  17. Blamire (2008)
  18. ^ Nettleship (1996)
  19. ^ Mahoney & Threlfall(1981)
  20. Vaughn (1937)
  21. Livezey (1988)
  22. Bédard (1985)
  23. Birkhead & Taylor (1977)
  24. Piatt, John F.; Nettleship, David N. (April 1985). "Diving depths of four alcids" (PDF). The Auk. 102 (2): 293–297. doi:10.2307/4086771. JSTOR 4086771.
  25. Mitchell et al. (2004)
  26. A massive die-off
  27. "Cape Meares State Scenic Viewpoint - Oregon State Parks and Recreation". oregonstateparks.org. Retrieved 2019-12-16.
  28. Buckingham, Lila; Bogdanova, Maria I.; Green, Jonathan A.; Dunn, Ruth E.; Wanless, Sarah; Bennett, Sophie; Bevan, Richard M.; Call, Andrew; Canham, Michael; Corse, Colin J.; Harris, Michael P.; Heward, Christopher J.; Jardine, David C.; Lennon, Jim; Parnaby, David; Redfern, Chris P. F.; Scott, Liz; Swann, Robert L.; Ward, Robin M.; Weston, Ewan D.; Furness, Robert W.; Daunt, Francis (17 February 2022). "Interspecific variation in non-breeding aggregation: a multi-colony tracking study of two sympatric seabirds". Marine Ecology Progress Series. 684: 181–197. Bibcode:2022MEPS..684..181B. doi:10.3354/meps13960. S2CID 244752949.
  29. Humphreys et al. (2007)
  30. Bragg, Julianna (26 December 2024). "The bird at the center of the worst single-species mortality event in modern history isn't recovering, scientists say". CNN. Retrieved 26 December 2024.
  31. ^ Lilliendahl et al. (2003)
  32. Harris et al. (2008)
  33. Bennett, Sophie; Wanless, Sarah; Harris, Mike P.; Newell, Mark A.; Searle, Kate R.; Green, Jonathan A.; Daunt, Francis (2022). "Site-dependent regulation of breeding success: Evidence for the buffer effect in the common guillemot, a colonially breeding seabird". Journal of Animal Ecology. 91 (4): 0–14. Bibcode:2022JAnEc..91..752B. doi:10.1111/1365-2656.13674. PMC 9305850. PMID 35157312. S2CID 246813729.
  34. ^ Lee, Derek E.; Abraham, Christine L.; Warzybok, Peter M.; Bradley, Russell W.; Sydeman, William J. (2008-04-01). "Age-Specific Survival, Breeding Success, and Recruitment in Common Murres (Uria Aalge) of the California Current System". The Auk. 125 (2): 316–325. doi:10.1525/auk.2008.07007. ISSN 0004-8038. S2CID 85018537.
  35. ^ Birkhead (1978)
  36. ^ Lewis et al. (2007)
  37. Kokko et al. (2004)
  38. ^ Moody et al. (2005)
  39. ^ Gaston & Jones (1998)
  40. ^ Birkhead, Tim R.; Thompson, Jamie E.; Montgomerie, Robert (1 October 2018). "The pyriform egg of the Common Murre (Uria aalge) is more stable on sloping surfacesEl huevo piriforme de Uria aalge es más estable en superficies inclinadasCommon Murre egg shape and stability". The Auk. 135 (4): 1020–1032. doi:10.1642/AUK-18-38.1.
  41. Johnson (1941)
  42. Birkhead, T. R.; Thompson, J. E.; Jackson, D.; Biggins, J. D. (2017). "The point of a Guillemot's egg" (PDF). Ibis. 159 (2): 255–265. doi:10.1111/ibi.12458.
  43. ^ Harris & Wanless (2006)
  44. Birkhead, Tim (2016). The Most Perfect Thing: Inside (and Outside) a Bird's Egg. London: Bloomsbury. p. 117.
  45. Gaston (1985)
  46. Wanless et al. (2005)
  47. Harris et al. (2000)
  48. Ashbrook et al. (2008)
  49. Harris & Wanless (2003)
  50. ^ Votier et al. (2008)
  51. ^ Harrison (2008)
  52. Barclay-Smith (1959)
  53. Beale (2007)
  54. Harding et al. (2007)
  55. White, Peter; (1995)

References

External links

Taxon identifiers
Uria aalge
Categories: