Editing Procellariidae (section)

===Food and feeding===
The diet of the procellariids is the most diverse of all the Procellariiformes, as are the methods employed to obtain it. With the exception of the [[giant petrel]]s, all procellariids are exclusively [[ocean|marine]], and the diet of all species is dominated by either fish, [[squid]], [[crustacean]]s and [[carrion]], or some combination thereof.{{sfn|Carboneras|1992a|pp=[https://archive.org/details/handbookofbirdso0001unse/page/223/mode/1up 223–224]}}

The majority of species are surface feeders, obtaining food that has been pushed to the surface by other predators or currents, or have floated in death. Among the surface feeders some, principally the gadfly petrels, can obtain food by dipping from flight, while most of the rest feed while sitting on the water. These surface feeders are dependent on their prey being close to the surface, and for this reason procellariids are often found in association with other predators or oceanic convergences. Studies have shown strong associations between many different kinds of [[seabird]]s, including [[wedge-tailed shearwater]]s, and [[dolphin]]s and [[tuna]], which push shoaling fish up towards the surface.<ref name = "AU"/> The gadfly petrels and the Kerguelen petrel mainly feed at night. In so doing they can take advantage of the nocturnal migration of cephalopods and other food species towards the surface.<ref name=Imber1985/><ref name=Harper1987>{{Cite journal | last=Harper | first=Peter C. | date=1987 | title=Feeding behaviour and other notes on 20 species of Procellariiformes at sea | journal=Notornis | volume=34 | issue=3 | pages=169–192 | url=https://notornis.osnz.org.nz/feeding-behaviour-and-other-notes-20-species-procellariiformes-sea | access-date=2022-01-30 | archive-date=2022-01-30 | archive-url=https://web.archive.org/web/20220130121359/https://notornis.osnz.org.nz/feeding-behaviour-and-other-notes-20-species-procellariiformes-sea | url-status=dead }}</ref>

The fulmarine petrels are generalists, which for the most part take many species of fish and crustacea. The giant petrels, uniquely for Procellariiformes, will feed on land, eating the carrion of other seabirds and [[pinniped|seals]]. They will also attack the chicks of other seabirds. The diet of the giant petrels varies according to sex, with the females taking more [[krill]] and the males more carrion.<ref name=j20/> All the fulmarine petrels readily feed on fisheries discards at sea, a habit that has been implicated in (but not proved to have caused) the expansion in range of the northern fulmar in the Atlantic.<ref>{{Cite book | last=Thompson | first=P.M. | chapter=Identifying drivers of change: did fisheries play a role in the spread of North Atlantic fulmars? | editor1-last=Boyd | editor1-first=I.L. | editor2-last=Wanless | editor2-first=S. | editor3-last=Camphuysen | editor3-first=C.J. | date=2006 | title=Top Predators in Marine Ecosystems: Their Role in Monitoring and Management | series=Conservation Biology | location=Cambridge, England |publisher=Cambridge University Press | isbn=978-0-521-61256-2 | pages=143–156 | archive-url=https://web.archive.org/web/20060823131229/http://www.abdn.ac.uk/zoology/lighthouse/documents/Thompson_fulmars.pdf | archive-date=2006-08-23 | chapter-url=http://www.abdn.ac.uk/zoology/lighthouse/documents/Thompson_fulmars.pdf}}</ref>
[[Image:Broad billed prion.jpg|thumb|The [[broad-billed prion]] (''Pachyptila vittata)'' filters zooplankton from the water with its wide bill. | alt=Photo of a broad-billed prion on land]]

The three larger prion species have bills filled with [[Lamellae (zoology)|lamellae]], which act as filters to sift [[zooplankton]] from the water. Water is forced through the lamellae and small prey items are collected. This technique is often used in conjunction with a method known as hydroplaning where the bird dips its bill beneath the surface and propels itself forward with wings and feet as if walking on the water.<ref name=j6/>{{sfn|Carboneras|1992a|p=[https://archive.org/details/handbookofbirdso0001unse/page/223/mode/1up 223]}}

The diving petrels and many of the shearwaters are proficient divers. While it has long been known that they regularly dive from the surface to pursue prey, using their wings for propulsion,{{sfn|Warham|1990|p=199}} the depth that they are able to dive to was not appreciated (or anticipated) until scientists began to deploy maximum-depth recorders on foraging birds. Studies of both long-distance migrants such as the sooty shearwater and more sedentary species such as the [[black-vented shearwater]] have shown maximum diving depths of {{convert|67|m|ft|abbr=on}} and {{convert|52|m|ft|abbr=on}}.<ref name=j5/><ref>{{Cite journal | last1=Navarro | first1=J. | last2=Votier | first2=S.C. | last3=Phillips | first3=R.A. | date=2014 | title=Diving capabilities of diving petrels | journal=Polar Biology | volume=37 | issue=6 | pages=897–901 | doi=10.1007/s00300-014-1483-0 | doi-access=free | bibcode=2014PoBio..37..897N | hdl=10261/108735 | hdl-access=free }} Supplementary Material.</ref> Tropical shearwaters, such as the wedge-tailed shearwater and the [[Sargasso shearwater]], also dive in order to hunt, making the shearwaters the only tropical seabirds capable of exploiting that ecological niche (all other tropical seabirds feed close to the surface).<ref name=j4/> Many other species of procellariid, from [[white-chinned petrel]]s to [[slender-billed prion]]s, dive to a couple of metres below the surface, though not as proficiently or as frequently as the shearwaters.<ref name=j3/>