View source for Shearwater

{{Short description|Seabird}}
{{Other uses}}
{{Paraphyletic group
| auto = yes
| name = Shearwaters
| image = Puffinus gravisPCCA20070623-3738B.jpg
| image_caption = [[Great shearwater]] 
| parent = Procellariidae
| diversity_link = List of shearwaters
| diversity = 3 genera and c. 30 species
| includes_text = Genera
| includes = 
*''[[Calonectris]]''
*''[[Puffinus]]''
*''[[Ardenna]]''
}}

'''Shearwaters''' are medium-sized long-winged [[seabird]]s in the [[petrel]] family [[Procellariidae]]. They have a global marine distribution, but are most common in temperate and cold waters, and are [[pelagic]] outside the breeding season.

==Description==
These [[Procellariiformes|tubenose birds]] fly with stiff wings and use a "shearing" flight technique (flying very close to the water and seemingly cutting or "shearing" the tips of waves) to move across wave fronts with the minimum of active flight. This technique gives the group its English name.<ref name=OED>{{Cite OED |Shearwaters }}</ref> Some small species like the [[Manx shearwater]] are [[cruciform]] in flight, with their long wings held directly out from their bodies.

==Behaviour==
===Movements===
Many shearwaters are long-distance migrants, perhaps most spectacularly [[sooty shearwater]]s, which cover distances in excess of {{convert|14000|km|mi|abbr=on}} from their breeding colonies on the [[Falkland Islands]] (52°S 60°W) to as far as 70° north latitude in the North Atlantic Ocean off northern Norway, and around [[New Zealand]] to as far as 60° north latitude in the North Pacific Ocean off Alaska. A 2006 study found individual tagged sooty shearwaters from New Zealand migrating {{convert|64000|km|mi|abbr=on}} a year,<ref name=Shaffer/> which gave them the then longest known animal migration ever recorded electronically (though subsequently greatly exceeded by a tagged [[arctic tern]] migrating {{convert|96000|km|mi|abbr=on}}<ref name=BBC/>). [[Short-tailed shearwater]]s perform an even longer "figure of eight" loop migration in the Pacific Ocean from [[Tasmania]] to as far north as the Arctic Ocean off northwest Alaska. They are also long-lived: a Manx shearwater breeding on [[Copeland Island]], Northern Ireland, was (as of 2003/2004) the oldest known wild bird in the world; [[Bird ringing|ringed]] as an adult (when at least 5 years old) in July 1953, it was retrapped in July 2003, at least 55 years old (also now exceeded, by a [[Laysan albatross]]). Manx shearwaters migrate over {{convert|10000|km|mi|abbr=on}} to South America in winter, using waters off southern Brazil and Argentina, so this bird had covered a minimum of {{convert|1000000|km|mi|abbr=on}} on migration alone. 

Following the tracks of the migratory [[Yelkouan shearwater]] has revealed that this species never flies overland, even if it means flying an extra 1,000 km. For instance, during their seasonal migration towards the Black Sea they would circumvent the entire [[Peloponnese]] instead of crossing over the 6 km [[Isthmus of Corinth]].<ref>CIESM Seabird Project. 2021. https://ciesm.org/marine/programs/seabirds/track-seabirds-migrating-live/ </ref>

===Breeding===
Shearwaters come to islands and coastal cliffs only to breed. They are nocturnal at the colonial breeding sites, preferring moonless nights to minimize predation. They nest in [[Burrow nest|burrows]] and often give eerie contact calls on their night-time visits. They lay a single white egg. The chicks of some species, notably short-tailed and sooty shearwaters, are subject to harvesting from their nest burrows for food, a practice known as [[muttonbirding]], in Australia and New Zealand.

===Feeding===
Shearwaters feed on fish, squid, and similar oceanic food. Some will follow fishing boats to take scraps, commonly the sooty shearwater; these species also commonly follow [[whale]]s to feed on fish disturbed by them. Their primary feeding technique is diving, with some species diving to depths of {{convert|70|m|ft|abbr=on}}.<ref name=Shaffer/> Shearwaters defecate more often than other seabirds, typically between once every four to ten minutes. They excrete five percent of their body mass every hour, generally done while flying, rather than while resting on water.<ref>{{Cite news |last=Preston |first=Elizabeth |date=2025-08-18 |title=These Majestic Seabirds Never Stop Pooping |url=https://www.nytimes.com/2025/08/18/science/seabirds-never-stop-pooping.html |access-date=2025-08-23 |work=[[The New York Times]] |language=en}}</ref><ref>{{Cite journal |last1=Uesaka |first1=Leo |last2=Sato |first2=Katsufumi |date=18 August 2025 |title=Periodic excretion patterns of seabirds in flight |url=https://linkinghub.elsevier.com/retrieve/pii/S0960982225008188 |journal=Current Biology |language=en |volume=35 |issue=16 |pages=R795–R796 |doi=10.1016/j.cub.2025.06.058 |pmid=40829559 |url-access=subscription }}</ref>

==Taxonomy==
There are about 30 [[species]]: a few larger ones in the genera ''[[Calonectris]]'' and ''[[Ardenna]]'' and many smaller ones in ''[[Puffinus]]''. Recent genomic studies show that Shearwaters form a clade with ''[[Procellaria]]'', ''[[Bulweria]]'' and ''[[Pseudobulweria]]''.<ref name="Estandia et al. 2021">{{cite journal |last1=Estandia |first1=A |last2=Chesser |first2=RT |last3=James |first3=HF |last4=Levy |first4=MA |last5=Ferrer Obiol |first5=J |last6=Bretagnolle |first6=V |last7=Gonzales-Solis |first7=J |last8=Welch |first8=AJ |title=Substitution rate variation in a robust procellariiform seabird phylogeny is not solely explained by body mass, flight efficiency, population size or life history traits |journal=bioRxiv |date=July 2021 |doi=10.1101/2021.07.27.453752|s2cid=236502443 |url=https://www.biorxiv.org/content/biorxiv/early/2021/07/27/2021.07.27.453752.full.pdf }}</ref> This arrangement contrasts with earlier conceptions based on mitochondrial [[DNA sequencing]]. <ref name=Bretagnolle/><ref name=Nunn/><ref name=Austin/>

===List of species===
The group contains 3 genera with 32 species.<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=August 2024 | title=Petrels, albatrosses | work=IOC World Bird List Version 14.2 | url=https://www.worldbirdnames.org/bow/petrels/ | publisher=International Ornithologists' Union | access-date=10 September 2024 }}</ref>
* ''[[Puffinus]]''
** [[Christmas shearwater]] ''Puffinus nativitatis''
** [[Manx shearwater]] ''Puffinus puffinus''
** [[Yelkouan shearwater]] ''Puffinus yelkouan''
** [[Balearic shearwater]] ''Puffinus mauretanicus'' (proposed lump with ''P. yelkouan'')
** [[Bryan's shearwater]] ''Puffinus bryani'' – first described in 2011
** [[Black-vented shearwater]] ''Puffinus opisthomelas''
** [[Townsend's shearwater]] ''Puffinus auricularis''
** [[Newell's shearwater]] ''Puffinus  newelli'' (split from Townsend's shearwater)
** [[Rapa shearwater]] ''Puffinus myrtae'' (split from Newell's shearwater)
** [[Fluttering shearwater]] ''Puffinus gavia''
** [[Hutton's shearwater]] ''Puffinus huttoni''
** [[Sargasso shearwater]] (formerly Audubon's shearwater, before splitting) ''Puffinus lherminieri''
** [[Persian shearwater]] ''Puffinus persicus'' (split from Audubon's shearwater)
** [[Tropical shearwater]] ''Puffinus bailloni'' (split from Audubon's shearwater)
** [[Galápagos shearwater]] ''Puffinus subalaris'' (split from Audubon's shearwater)
** [[Bannerman's shearwater]] ''Puffinus bannermani''
** [[Heinroth's shearwater]]  ''Puffinus heinrothi''
** [[Little shearwater]] ''Puffinus assimilis''
** [[Subantarctic shearwater]] ''Puffinus elegans'' (split from little shearwater)
** [[Barolo shearwater]] or Macronesian shearwater ''Puffinus baroli''
** [[Boyd's shearwater]] ''Puffinus boydi'' (split from Barolo shearwater)
* ''[[Calonectris]]''
** [[Streaked shearwater]] ''Calonectris leucomelas''
** [[Scopoli's shearwater]] ''Calonectris diomedea'' (split from Cory's shearwater)
** [[Cory's shearwater]] ''Calonectris diomedea'' 
** [[Cape Verde shearwater]] ''Calonectris edwardsii'' 
* ''[[Ardenna]]''
** [[Wedge-tailed shearwater]] ''Ardenna pacifica''
** [[Buller's shearwater]] ''Ardenna bulleri'' 
** [[Sooty shearwater]] ''Ardenna grisea'' 
** [[Short-tailed shearwater]] ''Ardenna tenuirostris'' 
** [[Pink-footed shearwater]] ''Ardenna creatopus'' 
** [[Flesh-footed shearwater]] ''Ardenna carneipes'' 
** [[Great shearwater]] ''Ardenna gravis''

There are two extinct species that have been described from fossils.
* † [[Lava shearwater]] or Olson's shearwater ''Puffinus olsoni''
* † [[Dune shearwater]] or Hole's shearwater ''Puffinus holeae''

===Phylogeny===
Phylogeny of the shearwaters based on a study by Joan Ferrer Obiol and collaborators published in 2022. Only 14 of the 21 recognised species in the genus ''[[Puffinus]]'' were included.<ref>{{Cite journal | last1=Ferrer Obiol | first1=J. | last2=James | first2=H.F. | last3=Chesser | first3=R.T. | last4=Bretagnolle | first4=V. | last5=González-Solís | first5=J. | last6=Rozas | first6=J. | last7=Welch | first7=A.J. | last8=Riutort | first8=M. | date=2022 | title=Palaeoceanographic changes in the late Pliocene promoted rapid diversification in pelagic seabirds | journal=Journal of Biogeography | volume=49 | issue=1 | pages=171–188 | doi=10.1111/jbi.14291 | doi-access=free | bibcode=2022JBiog..49..171F | hdl=2445/193747 | hdl-access=free }}</ref>
{{Clade
|1={{clade
   |label1=''[[Puffinus]]''
   |1={{clade
      |1=[[Christmas shearwater]] ''Puffinus nativitatis''
      |2={{clade
         |1={{clade
            |1=[[Fluttering shearwater]] ''Puffinus gavia''
            |2=[[Hutton's shearwater]] ''Puffinus huttoni''
            }}
         |2={{clade
            |1={{clade
               |1={{clade
                  |1=[[Audubon's shearwater]] ''Puffinus lherminieri''
                  |2={{clade
                     |1=[[Barolo shearwater]] ''Puffinus baroli''
                     |2=[[Boyd's shearwater]] ''Puffinus boydi''
                     }}
                  }}
               |2={{clade
                  |1=[[Manx shearwater]] ''Puffinus puffinus''
                  |2={{clade
                     |1=[[Balearic shearwater]] ''Puffinus mauretanicus''
                     |2=[[Yelkouan shearwater]] ''Puffinus yelkouan''
                     }}
                  }}
               }}
            |2={{clade
               |1={{clade
                  |1=[[Little shearwater]] ''Puffinus assimilis''
                  |2=[[Subantarctic shearwater]] ''Puffinus elegans''
                  }}
               |2={{clade
                  |1=[[Tropical shearwater]] ''Puffinus bailloni''
                  |2={{clade
                     |1=[[Black-vented shearwater]] ''Puffinus opisthomelas''
                     |2=[[Newell's shearwater]] ''Puffinus newelli''
                     }}
                  }}
               }}
            }}
         }}
      }}
   |2={{clade
      |label1=''[[Calonectris]]''
      |1={{clade
         |1=[[Streaked shearwater]] ''Calonectris leucomelas''
         |2={{clade
            |1=[[Cape Verde shearwater]] ''Calonectris edwardsii''
            |2={{clade
               |1=[[Cory's shearwater]] ''Calonectris borealis''
               |2=[[Scopoli's shearwater]] ''Calonectris diomedea''
               }}
            }}
         }}
      |label2=''[[Ardenna]]''
      |2={{clade
         |1={{clade
            |1=[[Buller's shearwater]] ''Ardenna bulleri''
            |2=[[Wedge-tailed shearwater]] ''Ardenna pacifica''
            }}
         |2={{clade
            |1=[[Short-tailed shearwater]] ''Ardenna tenuirostris''
            |2={{clade
               |1=[[Sooty shearwater]] ''Ardenna grisea''
               |2={{clade
                  |1=[[Great shearwater]] ''Ardenna gravis''
                  |2={{clade
                     |1=[[Flesh-footed shearwater]] ''Ardenna carneipes''
                     |2=[[Pink-footed shearwater]] ''Ardenna creatopus''
                     }}
                  }}
               }}
            }}
         }}
      }}
   }}
}}

==References==
{{reflist|refs=

<ref name=Bretagnolle>{{cite journal |last1=Bretagnolle |first1=Vincent |last2=Attié |first2=Carole |last3=Pasquet |first3=Eric |year=1998 |title=Cytochrome-''B'' evidence for validity and phylogenetic relationships of ''Pseudobulweria'' and ''Bulweria'' (Procellariidae) |journal=The Auk |doi=10.2307/4089123 |volume=115 |issue=1 |pages=188–195 |url=http://sora.unm.edu/sites/default/files/journals/auk/v115n01/p0188-p0195.pdf |jstor=4089123 }}</ref>

<ref name=Nunn>{{cite journal |last1=Nunn |first1=Gary B. |last2=Stanley |first2=Scott E. |year=1998 |title= Body Size Effects and Rates of Cytochrome ''b'' Evolution in Tube-Nosed Seabirds |journal=Molecular Biology and Evolution |doi=10.1093/oxfordjournals.molbev.a025864 |pmid=9787440 |volume=15 |issue=10 |pages=1360–1371 |doi-access=free }} [https://web.archive.org/web/20060823131221/http://mbe.oxfordjournals.org/cgi/reprint/17/11/1774.pdf Corrigendum]</ref>

<ref name=Austin>{{cite journal |last=Austin |first=Jeremy J. |year=1996 |title=Molecular Phylogenetics of ''Puffinus'' Shearwaters: Preliminary Evidence from Mitochondrial Cytochrome ''b'' Gene Sequences |journal=Molecular Phylogenetics and Evolution |doi=10.1006/mpev.1996.0060 |pmid=8812308 |volume=6 |issue=1 |pages= 77–88|bibcode=1996MolPE...6...77A }}</ref>

<ref name=Shaffer>{{cite journal |last1=Shaffer |first1=Scott A. |last2=Tremblay |first2=Yann |last3=Weimerskirch |first3=Henri |last4=Costa |first4=Daniel P. |year=2006 |title= Migratory shearwaters integrate oceanic resources across the Pacific Ocean in an endless summer |journal=PNAS |doi=10.1073/pnas.0603715103 |volume=103 |issue=34 |pages=12799–12802 |doi-access=free |pmid=16908846 |pmc=1568927 |bibcode=2006PNAS..10312799S }}</ref>

<ref name=BBC>{{cite news |title=Arctic tern in record-breaking migration from Farne Islands |url=https://www.bbc.co.uk/news/uk-england-tyne-36466763 |access-date=10 September 2024 |agency=BBC |date=7 June 2016}}</ref>

}}

==External links==
*[https://search.macaulaylibrary.org/catalog?taxonCode=procel3&includeChildTaxa=true&mediaType=video Shearwater videos] at the Macauley Library

[[Category:Shearwaters|*]]
[[Category:Seabirds]]
[[Category:Bird common names]]