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140-461: Alaska Maritime National Wildlife Refuge is well known for its abundance of seabirds . About 75 percent of Alaskan native marine birds, 15 to 30 million among 55 species, use the refuge. AMNWR also provides a nesting habitat for an estimated 40 million seabirds, representing 80 percent of all seabirds in North America . The birds congregate in "bird cities" (colonies) along the coast. Each species has

280-554: A cosmopolitan distribution across the world's oceans, with the highest diversity being around New Zealand . Procellariiforms are colonial , mostly nesting on remote, predator-free islands. The larger species nest on the surface, while most smaller species nest in natural cavities and burrows . They exhibit strong philopatry , returning to their natal colony to breed and returning to the same nesting site over many years. Procellariiforms are monogamous and form long-term pair bonds that are formed over several years and may last for

420-447: A murre colony. In most seabird colonies, several different species will nest on the same colony, often exhibiting some niche separation . Seabirds can nest in trees (if any are available), on the ground (with or without nests ), on cliffs, in burrows under the ground and in rocky crevices. Competition can be strong both within species and between species, with aggressive species such as sooty terns pushing less dominant species out of

560-401: A wreck . Seabirds have had a long association with both fisheries and sailors , and both have drawn benefits and disadvantages from the relationship. Fishermen have traditionally used seabirds as indicators of both fish shoals , underwater banks that might indicate fish stocks, and of potential landfall. In fact, the known association of seabirds with land was instrumental in allowing

700-601: A clade, the Aequornithes either became seabirds in a single transition in the Cretaceous or some lineages such as pelicans and frigatebirds adapted to sea living independently from freshwater-dwelling ancestors. In the Paleogene both pterosaurs and marine reptiles became extinct, allowing seabirds to expand ecologically. These post-extinction seas were dominated by early Procellariidae , giant penguins and two extinct families ,

840-499: A clear sky" with sun or stars visible, the shearwaters oriented themselves and then "flew off in a direct line for Skokholm", making the journey so rapidly that they must have flown almost in a straight line. But if the sky was overcast at the time of release, the shearwaters flew around in circles "as if lost" and returned slowly or not at all, implying that they navigated using astronomical cues. Researchers have also begun investigating olfaction's role in procellariiform navigation. In

980-535: A colony. Eggers from San Francisco took almost half a million eggs a year from the Farallon Islands in the mid-19th century, a period in the islands' history from which the seabird species are still recovering. Both hunting and egging continue today, although not at the levels that occurred in the past, and generally in a more controlled manner. For example, the Māori of Stewart Island / Rakiura continue to harvest

1120-576: A consistent pattern with the albatross family Diomedeidae as the most basal and Hydrobatidae sister to Procellariidae. There are 147 living species of procellariiform worldwide, and the order is divided into four extant families, with a fifth prehistorically extinct : Fossils of a bird similar to a petrel from the Eocene have been found in the London Clay and in Louisiana . Diving petrels occurred in

1260-405: A dense covering of white or grey down feathers , and the ability to move around the nesting site. After hatching, the incubating adult remains with the chick for a number of days, a period known as the guard phase. In the case of most burrow-nesting species, this is only until the chick is able to thermoregulate , usually two or three days. Diving-petrel chicks take longer to thermoregulate and have

1400-486: A fashion similar to grebes and loons (using its feet to move underwater) but had a beak filled with sharp teeth. Flying Cretaceous seabirds do not exceed wingspans of two meters; any sizes were taken by piscivorous pterosaurs . While Hesperornis is not thought to have left descendants, the earliest modern seabirds also occurred in the Cretaceous, with a species called Tytthostonyx glauconiticus , which has features suggestive of Procellariiformes and Fregatidae. As

1540-415: A few days to as much as several weeks, during which the incubating bird can lose a considerable amount of weight. The incubation period varies from species to species, around 40 days for the smallest storm-petrels but longer for the largest species; for albatrosses it can span 70 to 80 days, which is the longest incubation period of any bird. Upon hatching, the chicks are semi- precocial , having open eyes,

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1680-528: A generally tropical and temperate distribution, whereas the fulmarine petrels are mostly polar with some temperate species. The majority of the fulmarine petrels, along with the prions , are confined to the Southern Hemisphere. The storm petrels are almost as widespread as the procellariids, and fall into two distinct families; the Oceanitidae have a mostly Southern Hemisphere distribution and

1820-447: A great deal of time in their young. Most species nest in colonies , varying in size from a few dozen birds to millions. Many species are famous for undertaking long annual migrations , crossing the equator or circumnavigating the Earth in some cases. They feed both at the ocean's surface and below it, and even on each other. Seabirds can be highly pelagic , coastal, or in some cases spend

1960-936: A large number of non-governmental organizations (including BirdLife International , the American Bird Conservancy and the Royal Society for the Protection of Birds ). This led to the Agreement on the Conservation of Albatrosses and Petrels , a legally binding treaty designed to protect these threatened species, which has been ratified by thirteen countries as of 2021 (Argentina, Australia, Brazil, Chile, Ecuador, France, New Zealand, Norway, Peru, South Africa, Spain, Uruguay, United Kingdom). Many seabirds are little studied and poorly known because they live far out at sea and breed in isolated colonies. Some seabirds, particularly

2100-555: A lineage— Eurypygimorphae —that is a sister group to the Aequornithes. Seabirds, by virtue of living in a geologically depositional environment (that is, in the sea where sediments are readily laid down), are well represented in the fossil record. They are first known to occur in the Cretaceous period, the earliest being the Hesperornithiformes , like Hesperornis regalis , a flightless loon-like seabird that could dive in

2240-430: A long relationship with humans. They have been important food sources for many people, and continue to be hunted as such in some parts of the world. The albatrosses in particular have been the subject of numerous cultural depictions. Procellariiforms include some of the most endangered bird taxa , with many species threatened with extinction due to introduced predators in their breeding colonies, marine pollution and

2380-412: A longer guard phase than other burrow nesters. However, surface-nesting species, which have to deal with a greater range of weather and to contend with predators like skuas and frigatebirds , consequently have a longer guard phase (as long as two weeks in procellariids and three weeks in albatrosses). The chick is fed by both parents. Chicks are fed on fish, squid, krill, and stomach oil . Stomach oil

2520-576: A million birds have been recorded, both in the tropics (such as Kiritimati in the Pacific ) and in the polar latitudes (as in Antarctica ). Seabird colonies occur exclusively for the purpose of breeding; non-breeding birds will only collect together outside the breeding season in areas where prey species are densely aggregated. Seabird colonies are highly variable. Individual nesting sites can be widely spaced, as in an albatross colony, or densely packed as with

2660-456: A morphological adaptation to aid in flight, a sheet of tendon which locks the wing when fully extended, allowing the wing to be kept up and out without any muscle effort. Amongst the Oceanitinae storm-petrels there are two unique flight patterns, one being surface pattering. In this they move across the water surface holding and moving their feet on the water's surface while holding steady above

2800-693: A part of the year away from the sea entirely. Seabirds and humans have a long history together: They have provided food to hunters , guided fishermen to fishing stocks, and led sailors to land. Many species are currently threatened by human activities such as oil spills , nets, climate change and severe weather. Conservation efforts include the establishment of wildlife refuges and adjustments to fishing techniques. There exists no single definition of which groups, families and species are seabirds, and most definitions are in some way arbitrary. Elizabeth Shreiber and Joanna Burger, two seabird scientists, said, "The one common characteristic that all seabirds share

2940-414: A place for returning mates to reunite, and reduces the costs of prospecting for a new site. Young adults breeding for the first time usually return to their natal colony, and often nest close to where they hatched. This tendency, known as philopatry , is so strong that a study of Laysan albatrosses found that the average distance between hatching site and the site where a bird established its own territory

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3080-438: A reduced capacity for powered flight and are dependent on a type of gliding called dynamic soaring (where the wind deflected by waves provides lift) as well as slope soaring. Seabirds also almost always have webbed feet , to aid movement on the surface as well as assisting diving in some species. The Procellariiformes are unusual among birds in having a strong sense of smell , which is used to find widely distributed food in

3220-747: A rule this technique is rare. Some diving birds may aid diving by beginning with a plunge from the air, but for the most part petrels are active divers and use their wings to move around under the water. The depths achieved by various species were determined in the 1990s and came as a surprise to scientists; short-tailed shearwaters have been recorded diving to 70 m (230 ft) and the Light-mantled sooty albatross to 12 m (39 ft). All procellariiforms are colonial, predominantly breeding on offshore or oceanic islands. The few species that nest on continents do so in inhospitable environments such as dry deserts or on Antarctica. These colonies can vary from

3360-414: A single breeding attempt per nesting season; even if the egg is lost early in the season, they seldom re-lay. Much effort is placed into laying a single (proportionally) large egg and raising a single chick. Procellariiforms are long-lived: the longest living albatross known survived for 51 years, but was probably older, and even the tiny storm-petrels are known to have survived for 30 years. Additionally,

3500-649: A single night, probably when fed by both parents. The most important family culturally is the albatrosses, which have been described by one author as "the most legendary of birds". Albatrosses have featured in poetry in the form of Samuel Taylor Coleridge 's famous 1798 poem The Rime of the Ancient Mariner , which in turn gave rise to the usage of albatross as metaphor for a burden . More generally, albatrosses were believed to be good omens, and to kill one would bring bad luck. There are few instances of petrels in culture, although there are sailors' legends regarding

3640-461: A smaller layer of air (compared to other diving birds) but otherwise soak up water. This allows them to swim without fighting the buoyancy that retaining air in the feathers causes, yet retain enough air to prevent the bird losing excessive heat through contact with water. The plumage of most seabirds is less colourful than that of land birds, restricted in the main to variations of black, white or grey. A few species sport colourful plumes (such as

3780-575: A source of increasing concern to conservationists. The bycatch of seabirds entangled in nets or hooked on fishing lines has had a big impact on seabird numbers; for example, an estimated 100,000 albatrosses are hooked and drown each year on tuna lines set out by long-line fisheries. Overall, many hundreds of thousands of birds are trapped and killed each year, a source of concern for some of the rarest species (for example, only about 2,000 short-tailed albatrosses are known to still exist). Seabirds are also thought to suffer when overfishing occurs. Changes to

3920-515: A specialized nesting site (rock ledge, crevice, boulder rubble, pinnacle, or burrow). Other animals present in this refuge include caribou , sea lions , bears , coyotes , seals , Canada lynx , beavers , foxes , muskrats , wolf packs, moose , walrus , river otters , marten , whales , Dall sheep and sea otters . The administrative headquarters and visitor center are located in Homer, Alaska . In 1968, Simeonof National Wildlife Refuge, part of

4060-634: A study where Cory's shearwaters were rendered anosmic with zinc sulphate, a compound which kills the surface layer of the olfactory epithelium, and released hundreds of kilometers away from their home colony at night, control birds found their way to their home nests before night was over, whereas anosmic birds did not home until the next day. A similar study that released Cory's shearwaters 800 km from their home nests, testing both magnetic and olfactory disturbances’ effects on navigation, found that anosmic birds took longer to home than magnetically disturbed or control birds. Procellariiforms range in size from

4200-628: A successful breeding attempt). Procellariiforms are monogamous breeders and form long-term pair bonds. These pair bonds take several years to develop in some species, particularly with the albatrosses. Once formed, they last for many breeding seasons, in some cases for the life of the pair. Petrel courtship can be elaborate. It reaches its extreme with the albatrosses, where pairs spend many years perfecting and elaborating mating dances. These dances are composed of synchronised performances of various actions such as preening , pointing, calling, bill clacking, staring, and combinations of such behaviours (like

4340-552: A succession of bounding jumps. The procellariiforms are for the most part exclusively marine foragers ; the only exception to this rule are the two species of giant petrel, which regularly feed on carrion or other seabirds while on land. While some other species of fulmarine and Procellaria petrels also take carrion, the diet of most species of albatrosses and petrels is dominated by fish, squid, krill and other marine zooplankton. The importance of these food sources varies from species to species and family to family. For example, of

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4480-403: A vast ocean, and help distinguish familiar nest odours from unfamiliar ones. Salt glands are used by seabirds to deal with the salt they ingest by drinking and feeding (particularly on crustaceans ), and to help them osmoregulate . The excretions from these glands (which are positioned in the head of the birds, emerging from the nasal cavity ) are almost pure sodium chloride . With

4620-400: A very variable prey source); this may be a reason why it arises more frequently in seabirds. There are other possible advantages: colonies may act as information centres, where seabirds returning to the sea to forage can find out where prey is by studying returning individuals of the same species. There are disadvantages to colonial life, particularly the spread of disease. Colonies also attract

4760-454: A year, unless they lose the first (with a few exceptions, like the Cassin's auklet ), and many species (like the tubenoses and sulids ) will only lay one egg a year. Care of young is protracted, extending for as long as six months, among the longest for birds. For example, once common guillemot chicks fledge , they remain with the male parent for several months at sea. The frigatebirds have

4900-721: Is Frederick DuCane Godman 's Monograph of the Petrels , five fascicles, 1907–1910, with figures by John Gerrard Keulemans . In the Sibley-Ahlquist taxonomy , the tubenoses were included in a greatly enlarged order "Ciconiiformes". This taxonomic treatment was almost certainly erroneous, but its assumption of a close evolutionary relationship with other "higher waterbirds" – such as loons (Gaviiformes) and penguins (Sphenisciformes) – appears to be correct. The procellariiforms are most closely related to penguins, having diverged from them about 60 million years ago. The diving petrels in

5040-417: Is oil composed of neutral dietary lipids that are the residue created by digestion of the prey items. As an energy source for chicks it has several advantages over undigested prey, its calorific value is around 9.6 kcal per gram, which is only slightly lower than the value for diesel oil. This can be a real advantage for species that range over huge distances to provide food for hungry chicks. The oil

5180-462: Is also fed to their young, as well as being used for defense. Procellariiforms drink seawater, so they have to excrete excess salt. All birds have an enlarged nasal gland at the base of the bill, above the eyes, and in the Procellariiformes the gland is active. In general terms, the salt gland removes salt from the system and forms a 5 percent saline solution that drips out of the nostrils, or

5320-428: Is also used in defence. All procellariiforms create stomach oil except the diving-petrels. The chick fledges between two and nine months after hatching, almost twice as long as a gull of the same body mass. The reasons behind the length of time are associated with the distance from the breeding site to food. First, there are few predators at the nesting colonies, therefore there is no pressure to fledge quickly. Second,

5460-488: Is attractive to foraging birds and many are hooked by the lines as they are set. As many as 100,000 albatrosses are hooked and drown each year on tuna lines set out by long-line fisheries. Before 1991 and the ban on drift-net fisheries , it was estimated that 500,000 seabirds a year died as a result. This has caused steep declines in some species, as procellariiforms are extremely slow breeders and cannot replace their numbers fast enough. Losses of albatrosses and petrels in

5600-407: Is energetically inefficient in warmer waters. With their poor flying ability, many wing-propelled pursuit divers are more limited in their foraging range than other guilds. Gannets , boobies , tropicbirds , some terns, and brown pelicans all engage in plunge diving, taking fast-moving prey by diving into the water from the flight. Plunge diving allows birds to use the energy from the momentum of

5740-594: Is forcibly ejected in some petrels. The processes behind this involve high levels of sodium ion reabsorption into the blood plasma within the kidneys, and secretion of sodium chloride via the salt glands using less water than was absorbed, which essentially generates salt-free water for other physiological uses. This high efficiency of sodium ion absorption is attributed to mammalian-type nephrons . Most albatrosses and procellariids use two techniques to minimise exertion while flying, namely, dynamic soaring and slope soaring . The albatrosses and giant petrels share

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5880-642: Is inconclusive. Some plunge divers (as well as some surface feeders) are dependent on dolphins and tuna to push shoaling fish up towards the surface. This catch-all category refers to other seabird strategies that involve the next trophic level up. Kleptoparasites are seabirds that make a part of their living stealing food of other seabirds. Most famously, frigatebirds and skuas engage in this behaviour, although gulls, terns and other species will steal food opportunistically. The nocturnal nesting behaviour of some seabirds has been interpreted as arising due to pressure from this aerial piracy. Kleptoparasitism

6020-518: Is non-consumptive, it can have deleterious effects that need careful management to protect both the birds and the tourism. The English naturalist William Yarrell wrote in 1843 that "ten or twelve years ago, Mr. Gould exhibited twenty-four [storm petrels], in a large dish, at one of the evening meetings of the Zoological Society ". The engraver Thomas Bewick wrote in 1804 that " Pennant , speaking of those [birds] which breed on, or inhabit,

6160-545: Is not thought to play a significant part of the diet of any species, and is instead a supplement to food obtained by hunting. A study of great frigatebirds stealing from masked boobies estimated that the frigatebirds could at most obtain 40% of the food they needed, and on average obtained only 5%. Many species of gull will feed on seabird and sea mammal carrion when the opportunity arises, as will giant petrels . Some species of albatross also engage in scavenging: an analysis of regurgitated squid beaks has shown that many of

6300-402: Is often a problem as well—visitors, even well-meaning tourists, can flush brooding adults off a colony, leaving chicks and eggs vulnerable to predators. The build-up of toxins and pollutants in seabirds is also a concern. Seabirds, being apex predators , suffered from the ravages of the insecticide DDT until it was banned; DDT was implicated, for example, in embryo development problems and

6440-456: Is punished for killing an albatross by having to wear its corpse around his neck. Sailors did, however, consider it unlucky to touch a storm petrel, especially one that landed on the ship. Procellariiformes † Diomedeoididae Procellariidae Diomedeidae Hydrobatidae Oceanitidae Procellariiformes / p r ɒ s ɛ ˈ l ɛər i . ɪ f ɔːr m iː z / is an order of seabirds that comprises four families :

6580-464: Is site fidelity, where pairs of birds return to the same nesting site for a number of years. Among the most extreme examples known of this tendency was the fidelity of a ringed northern fulmar that returned to the same nest site for 25 years. The average number of birds returning to the same nest sites is high in all species studied, with around 91 percent for Bulwer's petrels , and 85 percent of males and 76 percent of females for Cory's shearwaters (after

6720-484: Is some evidence of this, the effects of seabirds are considered smaller than that of marine mammals and predatory fish (like tuna ). Some seabird species have benefited from fisheries, particularly from discarded fish and offal . These discards compose 30% of the food of seabirds in the North Sea , for example, and compose up to 70% of the total food of some seabird populations. This can have other impacts; for example,

6860-756: Is that they feed in saltwater ; but, as seems to be true with any statement in biology, some do not." However, by convention all of the Sphenisciformes (penguins) and Procellariiformes ( albatrosses and petrels ), all of the Suliformes ( gannets and cormorants ) except the darters , and some of the Charadriiformes (the gulls , skuas , terns , auks and skimmers ) are classified as seabirds. The phalaropes are usually included as well, since although they are waders ("shorebirds" in North America), two of

7000-589: Is the skimmer , which has a unique fishing method: flying along the surface with the lower mandible in the water—this shuts automatically when the bill touches something in the water. The skimmer's bill reflects its unusual lifestyle, with the lower mandible uniquely being longer than the upper one. Surface feeders that swim often have unique bills as well, adapted for their specific prey. Prions have special bills with filters called lamellae to filter out plankton from mouthfuls of water, and many albatrosses and petrels have hooked bills to snatch fast-moving prey. On

7140-448: Is the deepest diver of the shearwaters, having been recorded diving below 70 metres (230 ft). Some albatross species are also capable of limited diving, with light-mantled sooty albatrosses holding the record at 12 metres (40 ft). Of all the wing-propelled pursuit divers, the most efficient in the air are the albatrosses, and they are also the poorest divers. This is the dominant guild in polar and subpolar environments, but it

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7280-424: Is the small area around either the nest or a burrow. Competition between pairs can be intense, as is competition between species, particularly for burrows. Larger species of petrels will even kill the chicks and even adults of smaller species in disputes over burrows. Burrows and natural crevices are most commonly used by the smaller species; all the storm petrels and diving petrels are cavity nesters, as are many of

7420-572: The Fiji petrel has rarely been seen since its discovery. The breeding colony of the New Zealand storm petrel was not located until February 2013; it had been thought extinct for 150 years until its rediscovery in 2003, while the Bermuda petrel had been considered extinct for nearly 300 years. The principal threat to the albatrosses and larger species of procellariids is long-line fishing . Bait set on hooks

7560-538: The Hydrobatidae are found mostly in the Northern Hemisphere. Amongst the albatrosses the majority of the family is restricted to the Southern Hemisphere, feeding and nesting in cool temperate areas, although one genus, Phoebastria , ranges across the north Pacific. The family is absent from the north Atlantic, although fossil records indicate they bred there once. Finally the diving petrels are restricted to

7700-621: The Isle of St Kilda , says—'No bird is of so much use to the islanders as this: the Fulmar supplies them with oil for their lamps, down for their beds, a delicacy for their tables, a balm for their wounds, and a medicine for their distempers.'" A photograph by George Washington Wilson taken about 1886 shows a "view of the men and women of St Kilda on the beach dividing up the catch of Fulmar". James Fisher, author of The Fulmar (1952) calculated that every person on St Kilda consumed over 100 fulmars each year;

7840-630: The Māori of New Zealand use a sustainable traditional method known as kaitiakitanga . In Alaska, residents of Kodiak Island harpoon short-tailed albatrosses , Diomedea albatrus , and until the late 1980s residents of Tristan Island in the Indian Ocean harvested the eggs of the Yellow-nosed Mollymawks , Diomedea chlororhynchos , and sooty albatrosses , Phoebetria fusca . Albatrosses and petrels are also now tourist draws in some locations, such as Taiaroa Head . While such exploitation

7980-684: The Pelagornithidae and the Plotopteridae (a group of large seabirds that looked like the penguins). Modern genera began their wide radiation in the Miocene , although the genus Puffinus (which includes today's Manx shearwater and sooty shearwater ) might date back to the Oligocene . Within the Charadriiformes, the gulls and allies ( Lari ) became seabirds in the late Eocene, and then waders in

8120-692: The Polynesians to locate tiny landmasses in the Pacific. Seabirds have provided food for fishermen away from home, as well as bait. Famously, tethered cormorants have been used to catch fish directly. Indirectly, fisheries have also benefited from guano from colonies of seabirds acting as fertilizer for the surrounding seas. Negative effects on fisheries are mostly restricted to raiding by birds on aquaculture , although long-lining fisheries also have to deal with bait stealing. There have been claims of prey depletion by seabirds of fishery stocks, and while there

8260-555: The Wilson's storm petrel and the Providence petrel , but no albatrosses cross the equator, as they rely on wind assisted flight. There are other long-distance migrants within the order; Swinhoe's storm petrels breed in the western Pacific and migrate to the western Indian Ocean, and Bonin petrels nesting in Hawaii migrate to the coast of Japan during the non-breeding season. Many species in

8400-471: The albatrosses , the petrels and shearwaters , and two families of storm petrels . Formerly called Tubinares and still called tubenoses in English, procellariiforms are often referred to collectively as the petrels , a term that has been applied to all members of the order, or more commonly all the families except the albatrosses. They are almost exclusively pelagic (feeding in the open ocean), and have

8540-482: The bill , which contains seven to nine distinct horny plates, is another unifying feature, although there are differences within the order. Petrels have a plate called the maxillary unguis that forms a hook on the maxilla. The smaller members of the order have a comb-like mandible, made by the tomial plate, for plankton feeding. Most members of the order are unable to walk well on land, and many species visit their remote breeding islands only at night. The exceptions are

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8680-518: The burevestnik name is applied in Russian (it, in fact, is known in Russian as an entirely un-romantic kachurka ), the English translators uniformly used the "stormy petrel" image in their translations of the poem, usually known in English as The Song of the Stormy Petrel . Various tubenose birds are relevant to the mythologies and oral traditions of Polynesia . The Māori used the wing bones of

8820-455: The marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution , as the same environmental problems and feeding niches have resulted in similar adaptations. The first seabirds evolved in the Cretaceous period , and modern seabird families emerged in the Paleogene . Seabirds generally live longer, breed later and have fewer young than other birds, but they invest

8960-669: The millinery trade reached industrial levels. Muttonbirding (harvesting shearwater chicks) developed as important industries in both New Zealand and Tasmania, and the name of one species, the providence petrel , is derived from its seemingly miraculous arrival on Norfolk Island where it provided a windfall for starving European settlers. In the Falkland Islands , hundreds of thousands of penguins were harvested for their oil each year. Seabird eggs have also long been an important source of food for sailors undertaking long sea voyages, as well as being taken when settlements grow in areas near

9100-581: The procellariids . The fulmarine petrels and some tropical gadfly petrels and shearwaters are surface nesters, as are all the albatrosses. Procellariiforms show high levels of philopatry , both site fidelity and natal philopatry. Natal philopatry is the tendency of an individual bird to return to its natal colony to breed, often many years after leaving the colony as a chick. This tendency has been shown through ringing studies and mitochondrial DNA studies. Birds ringed as chicks have been recaptured close to their original nests, sometimes extremely close; in

9240-419: The razorbill (an Atlantic auk) requires 64% more energy to fly than a petrel of equivalent size. Many shearwaters are intermediate between the two, having longer wings than typical wing-propelled divers but heavier wing loadings than the other surface-feeding procellariids , leaving them capable of diving to considerable depths while still being efficient long-distance travellers. The short-tailed shearwater

9380-481: The shearwaters and gadfly petrels). Surface feeders in flight include some of the most acrobatic of seabirds, which either snatch morsels from the water (as do frigate-birds and some terns), or "walk", pattering and hovering on the water's surface, as some of the storm-petrels do. Many of these do not ever land in the water, and some, such as the frigatebirds, have difficulty getting airborne again should they do so. Another seabird family that does not land while feeding

9520-596: The short-tailed shearwater (23 million individuals); while the total population of some other species is a few hundred. There are less than 200 Magenta petrels breeding on the Chatham Islands , only 130 to 160 Zino's petrels and only 170 Amsterdam albatrosses . Only one species is thought to have become extinct since 1600, the Guadalupe storm petrel of Mexico , although a number of species had died out before this. Numerous species are very poorly known; for example,

9660-882: The Alaska Maritime National Wildlife Refuge, was designated as a National Natural Landmark by the National Park Service. The refuge is divided into five units. Clockwise around Alaska, starting in the southeast, their component territories include: Includes most of the land area of the Aleutian Islands , from Unimak in the east to Attu in the west: Near Islands , Rat Islands , Delarof Islands , Andreanof Islands , Islands of Four Mountains , Fox Islands , and Krenitzin Islands Seabird Seabirds (also known as marine birds ) are birds that are adapted to life within

9800-515: The Antarctic mainland, are unlikely to find anything to eat around their breeding sites. The marbled murrelet nests inland in old growth forest , seeking huge conifers with large branches to nest on. Other species, such as the California gull , nest and feed inland on lakes, and then move to the coasts in the winter. Some cormorant, pelican , gull and tern species have individuals that never visit

9940-625: The Arctic tern; birds that nest in New Zealand and Chile and spend the northern summer feeding in the North Pacific off Japan, Alaska and California, an annual round trip of 64,000 kilometres (40,000 mi). Other species also migrate shorter distances away from the breeding sites, their distribution at sea determined by the availability of food. If oceanic conditions are unsuitable, seabirds will emigrate to more productive areas, sometimes permanently if

10080-700: The Austral summer in Antarctica. Other species also undertake trans-equatorial trips, both from the north to the south, and from south to north. The population of elegant terns , which nest off Baja California , splits after the breeding season with some birds travelling north to the Central Coast of California and some travelling as far south as Peru and Chile to feed in the Humboldt Current . The sooty shearwater undertakes an annual migration cycle that rivals that of

10220-553: The Laysan albatross the average distance between hatching site and the site where a bird established its own territory was 22 m (72 ft), and a study of Cory's shearwaters nesting near Corsica found that nine out of 61 male chicks that returned to breed at their natal colony actually bred in the burrow they were raised in. Mitochondrial DNA provides evidence of restricted gene flow between different colonies, strongly suggesting philopatry. The other type of philopatry exhibited

10360-632: The Miocene, with a species from that family ( Pelecanoides miokuaka ) being described in 2007. The most numerous fossils from the Paleogene are those from the extinct family Diomedeoididae, fossils of which have been found in Central Europe and Iran. The procellariiforms have a cosmopolitan distribution across the world's oceans and seas, although at the levels of family and genus there are some clear patterns. Antarctic petrels , Thalassoica antarctica , have to fly over 100 mi (160 km) to get to

10500-529: The Southern Hemisphere. The various species within the order have a variety of migration strategies. Some species undertake regular trans-equatorial migrations, such as the sooty shearwater which annually migrates from its breeding grounds in New Zealand and Chile to the North Pacific off Japan , Alaska and California, an annual round trip of 64,000 km (40,000 mi), the second longest measured annual migration of any bird. A number of other petrel species undertake trans-equatorial migrations, including

10640-556: The Southern Ocean were estimated at between 1 percent and 16 percent per year, which these species cannot sustain for long. Exotic species introduced to the remote breeding colonies threaten all types of procellariiform. These principally take the form of predators ; most albatross and petrel species are clumsy on land and unable to defend themselves from mammals such as rats , feral cats and pigs . This phenomenon, ecological naivete , has resulted in declines in many species and

10780-543: The UK was the Scottish Seabird Centre , near the important bird sanctuaries on Bass Rock , Fidra and the surrounding islands. The area is home to huge colonies of gannets, puffins , skuas and other seabirds. The centre allows visitors to watch live video from the islands as well as learn about the threats the birds face and how we can protect them, and has helped to significantly raise the profile of seabird conservation in

10920-480: The UK. Seabird tourism can provide income for coastal communities as well as raise the profile of seabird conservation, although it needs to be managed to ensure it does not harm the colonies and nesting birds. For example, the northern royal albatross colony at Taiaroa Head in New Zealand attracts 40,000 visitors a year. The plight of albatross and large seabirds, as well as other marine creatures, being taken as bycatch by long-line fisheries, has been addressed by

11060-430: The albatross to carve flutes . In Hawaiian mythology , Laysan albatrosses are considered aumakua , being a sacred manifestation of the ancestors, and quite possibly also the sacred bird of Kāne . The storm petrel features prominently in the "Origin of Birds" myth. Albatrosses and petrels have been important food sources for humans for as long as people have been able to reach their remote breeding colonies. Amongst

11200-402: The albatrosses and gulls, are more well known to humans. The albatross has been described as "the most legendary of birds", and have a variety of myths and legends associated with them. While it is widely considered unlucky to harm them, the notion that sailors believed that is a myth that derives from Samuel Taylor Coleridge 's famous poem, " The Rime of the Ancient Mariner ", in which a sailor

11340-448: The attention of predators , principally other birds, and many species attend their colonies nocturnally to avoid predation. Birds from different colonies often forage in different areas to avoid competition. Like many birds, seabirds often migrate after the breeding season . Of these, the trip taken by the Arctic tern is the farthest of any bird, crossing the equator in order to spend

11480-454: The bird is young. After fledging, juvenile birds often disperse further than adults, and to different areas, so are commonly sighted far from a species' normal range. Some species, such as the auks, do not have a concerted migration effort, but drift southwards as the winter approaches. Other species, such as some of the storm petrels, diving petrels and cormorants, never disperse at all, staying near their breeding colonies year round. While

11620-500: The chances of successfully fledging. Procellariids are also vulnerable to marine pollution , as well as oil spills . Some species, such as Barau's petrel , Newell's shearwater and Cory's shearwater, which nest high up on large developed islands, are victims of light pollution. Fledging chicks are attracted to streetlights and may then be unable to reach the sea. An estimated 20 to 40 percent of fledging Barau's petrels and 45 to 60 percent of fledging Cory's shearwater are attracted to

11760-480: The chicks of the sooty shearwater as they have done for centuries, using traditional stewardship, kaitiakitanga , to manage the harvest, but now also work with the University of Otago in studying the populations. In Greenland , however, uncontrolled hunting is pushing many species into steep decline. Other human factors have led to declines and even extinctions in seabird populations and species. Of these, perhaps

11900-544: The danger of fisheries by-catch . Scientists, conservationists, fishermen, and governments around the world are working to reduce the threats posed to them, and these efforts have led to the signing of the Agreement on the Conservation of Albatrosses and Petrels , a legally binding international treaty signed in 2001. Diomedeidae – albatrosses (21 species) Oceanitidae – austral storm petrels (10 species) Hydrobatidae – northern storm petrels (18 species) Procellariidae – petrels and shearwaters (100 species) The order

12040-453: The definition of seabirds suggests that the birds in question spend their lives on the ocean, many seabird families have many species that spend some or even most of their lives inland away from the sea. Most strikingly, many species breed tens, hundreds or even thousands of miles inland. Some of these species still return to the ocean to feed; for example, the snow petrel , the nests of which have been found 480 kilometres (300 mi) inland on

12180-451: The disease have scarred digestive tracts from ingesting plastic waste . "When birds ingest small pieces of plastic, they found, it inflames the digestive tract. Over time, the persistent inflammation causes tissues to become scarred and disfigured, affecting digestion, growth and survival." The threats faced by seabirds have not gone unnoticed by scientists or the conservation movement . As early as 1903, U.S. President Theodore Roosevelt

12320-456: The dive to combat natural buoyancy (caused by air trapped in plumage), and thus uses less energy than the dedicated pursuit divers, allowing them to utilise more widely distributed food resources, for example, in impoverished tropical seas. In general, this is the most specialised method of hunting employed by seabirds; other non-specialists (such as gulls and skuas) may employ it but do so with less skill and from lower heights. In brown pelicans,

12460-413: The earliest instances known is in southern Chile, where archaeological excavations in middens has shown hunting of albatrosses, cormorants and shearwaters from 5000 BP. This pressure has led to some species becoming extinct in many places; in particular, at least 20 species of an original 29 no longer breed on Easter Island . In the 19th century, the hunting of seabirds for fat deposits and feathers for

12600-508: The earliest-known examples of this is the remains of shearwaters and albatrosses along with those of other seabirds in 5,000-year-old middens in Chile , although it is likely that they were exploited prior to this. Since then, many other marine cultures, both subsistence and industrial, have exploited procellariiforms, in some cases almost to extinction . Some cultures continue to harvest shearwaters (a practice known as muttonbirding ); for example,

12740-404: The exception of the cormorants and some terns, and in common with most other birds, all seabirds have waterproof plumage . However, compared to land birds, they have far more feathers protecting their bodies. This dense plumage is better able to protect the bird from getting wet, and cold is kept out by a dense layer of down feathers . The cormorants possess a layer of unique feathers that retain

12880-676: The feathers resist abrasion. Seabirds evolved to exploit different food resources in the world's seas and oceans, and to a great extent, their physiology and behaviour have been shaped by their diet . These evolutionary forces have often caused species in different families and even orders to evolve similar strategies and adaptations to the same problems, leading to remarkable convergent evolution , such as that between auks and penguins. There are four basic feeding strategies, or ecological guilds, for feeding at sea: surface feeding, pursuit diving, plunge-diving, and predation of higher vertebrates ; within these guilds, there are multiple variations on

13020-706: The feet are webbed, and the hind toe is undeveloped or non-existent; their adult plumage is predominantly black, white, and grey. The order has a few unifying characteristics, starting with their tubular nasal passage which is used for olfaction . Procellariiformes that nest in burrows have a strong sense of smell, being able to detect dimethyl sulfide released from plankton in the ocean. This ability to smell helps to locate patchily distributed prey at sea and may also help locate their nests within nesting colonies . In contrast, surface nesting Procellariiformes have increased vision, having six times better spatial resolution than those that nest in burrows. The structure of

13160-466: The first time in over a hundred years. Seabird mortality caused by long-line fisheries can be greatly reduced by techniques such as setting long-line bait at night, dying the bait blue, setting the bait underwater, increasing the amount of weight on lines and by using bird scarers, and their deployment is increasingly required by many national fishing fleets. One of the Millennium Projects in

13300-446: The forest understory on Cabbage Tree Island off New South Wales , which increased the vulnerability of the Gould's petrels nesting on the island to natural predators, and left them vulnerable to the sticky fruits of the native birdlime tree ( Pisonia umbellifera ). In the natural state these fruits lodge in the understory of the forest, but with the understory removed the fruits fall to

13440-478: The frequency of breeding failures due to unfavourable marine conditions, and the relative lack of predation compared to that of land-living birds. Because of the greater investment in raising the young and because foraging for food may occur far from the nest site, in all seabird species except the phalaropes, both parents participate in caring for the young, and pairs are typically at least seasonally monogamous . Many species, such as gulls, auks and penguins, retain

13580-434: The genus Pelecanoides were formerly placed in their own family Pelecanoididae. When genetic studies found that they were embedded within the family Procellariidae, the two families were merged. All the storm petrels were once placed in the family Hydrobatidae but genetic data indicated that Hydrobatidae consisted of two deeply divergent clades that were not sister taxa. In 2018 the austral storm petrels were moved to

13720-484: The ground where the petrels move about, sticking to their feathers and making flight impossible. Exploitation has decreased in importance as a threat. Other threats include the ingestion of plastic flotsam . Once swallowed, plastic can cause a general decline in the fitness of the bird, or in some cases lodge in the gut and cause a blockage, leading to death by starvation. It can also be picked up by foraging adults and fed to chicks, stunting their development and reducing

13860-444: The huge albatrosses, several of the gadfly petrels and shearwaters and the fulmar-petrels. The latter can disable even large predatory birds with their obnoxious stomach oil , which they can project some distance. This stomach oil, stored in the proventriculus , is a digestive residue created in the foregut of all tubenoses except the diving petrels, and is used mainly for storage of energy-rich food during their long flights. The oil

14000-414: The life of the pair. A single egg is laid per nesting attempt, and usually a single nesting attempt is made per year, although the larger albatrosses may only nest once every two years. Both parents participate in incubation and chick rearing. Incubation times are long compared to other birds, as are fledging periods. Once a chick has fledged there is no further parental care. Procellariiforms have had

14140-468: The longest period of parental care of any bird except a few raptors and the southern ground hornbill , with each chick fledging after four to six months and continued assistance after that for up to fourteen months. Due to the extended period of care, breeding occurs every two years rather than annually for some species. This life-history strategy has probably evolved both in response to the challenges of living at sea (collecting widely scattered prey items),

14280-408: The marine ecosystems caused by dredging, which alters the biodiversity of the seafloor, can also have a negative impact. The hunting of seabirds and the collecting of seabird eggs have contributed to the declines of many species, and the extinction of several, including the great auk and the spectacled cormorant . Seabirds have been hunted for food by coastal peoples throughout history—one of

14420-494: The meat was their staple food, and they caught around 12,000 birds annually. However, when the human population left St Kilda in 1930, the population did not suddenly grow. The albatrosses and petrels are "amongst the most severely threatened taxa worldwide". They face a variety of threats, the severity of which varies greatly from species to species. Several species are among the most common of seabirds, including Wilson's storm petrel (an estimated 12 to 30 million individuals) and

14560-569: The middle Miocene ( Langhian ). The highest diversity of seabirds apparently existed during the Late Miocene and the Pliocene . At the end of the latter, the oceanic food web had undergone a period of upheaval due to extinction of considerable numbers of marine species; subsequently, the spread of marine mammals seems to have prevented seabirds from reaching their erstwhile diversity. Seabirds have made numerous adaptations to living on and feeding in

14700-490: The most desirable nesting spaces. The tropical Bonin petrel nests during the winter to avoid competition with the more aggressive wedge-tailed shearwater . When the seasons overlap, the wedge-tailed shearwaters will kill young Bonin petrels in order to use their burrows. Many seabirds show remarkable site fidelity , returning to the same burrow, nest or site for many years, and they will defend that site from rivals with great vigour. This increases breeding success, provides

14840-552: The most serious are introduced species . Seabirds, breeding predominantly on small isolated islands, are vulnerable to predators because they have lost many behaviours associated with defence from predators. Feral cats can take seabirds as large as albatrosses, and many introduced rodents, such as the Pacific rat , take eggs hidden in burrows. Introduced goats, cattle, rabbits and other herbivores can create problems, particularly when species need vegetation to protect or shade their young. The disturbance of breeding colonies by humans

14980-444: The new family Oceanitidae. The northern storm petrels in the family Hydrobatidae are more closely related to the family Procellariidae than they are to the austral storm petrels in the family Oceanitidae. Earlier molecular phylogenetic studies found the family Oceantidae containing the austral storm petrels as the most basal with differing branching topologies for other three families. More recent large-scale studies have found

15120-657: The ocean from their breeding colonies in Antarctica , and northern fulmars breed on the northeastern tip of Greenland , the northernmost piece of land . The most cosmopolitan family is the Procellariidae , which are found in tropical, temperate and polar zones of both the Northern and the Southern Hemispheres, though the majority do not breed in the tropics, and half the species are restricted to southern temperate and polar regions. The gadfly petrels, Pterodroma , have

15260-428: The ocean lead to decreased availability of food and colonies are more often flooded as a consequence of sea level rise and extreme rainfall events. Heat stress from extreme temperatures is an additional threat. Some seabirds have used changing wind patterns to forage further and more efficiently. In 2023, plasticosis , a new disease caused solely by plastics, was discovered in seabirds. The birds identified as having

15400-517: The oldest living bird is Wisdom , a female Laysan albatross. The majority of procellariiforms nest once a year and do so seasonally. Some tropical shearwaters, like the Christmas shearwater , are able to nest on cycles slightly shorter than a year, and the large great albatrosses (genus Diomedea ) nest in alternate years (if successful). Most temperate and polar species nest over the spring-summer, although some albatrosses and procellariids nest over

15540-543: The order travel long distances over open water but return to the same nest site each year, raising the question of how they navigate so accurately. The Welsh naturalist Ronald Lockley carried out early research into animal navigation with the Manx shearwaters that nested on the island of Skokholm . In release experiments, a Manx shearwater flew from Boston to Skokholm, a distance of 3,000 miles (4,800 kilometres) in 12 1 ⁄ 2 days. Lockley showed that when released "under

15680-841: The other hand, most gulls are versatile and opportunistic feeders who will eat a wide variety of prey, both at sea and on land. Pursuit diving exerts greater pressures (both evolutionary and physiological) on seabirds, but the reward is a greater area in which to feed than is available to surface feeders. Underwater propulsion is provided by wings (as used by penguins, auks, diving petrels and some other species of petrel) or feet (as used by cormorants, grebes , loons and several types of fish-eating ducks ). Wing-propelled divers are generally faster than foot-propelled divers. The use of wings or feet for diving has limited their utility in other situations: loons and grebes walk with extreme difficulty (if at all), penguins cannot fly, and auks have sacrificed flight efficiency in favour of diving. For example,

15820-452: The quality of potential mates. After pairs have been formed, calls serve to help them reunite; the ability of individuals to recognise their own mate has been demonstrated in several species. Procellariiforms are K-selected , being long-lived and caring extensively for their few offspring. Breeding is delayed for several years after fledging , sometimes for as long as ten years in the largest species. Once they begin breeding, they make only

15960-437: The removal of exotic invaders from increasingly large islands. Feral cats have been removed from Ascension Island , Arctic foxes from many islands in the Aleutian Islands , and rats from Campbell Island . The removal of these introduced species has led to increases in numbers of species under pressure and even the return of extirpated ones. After the removal of cats from Ascension Island, seabirds began to nest there again for

16100-465: The same mate for several seasons, and many petrel species mate for life. Albatrosses and procellariids , which mate for life, take many years to form a pair bond before they breed, and the albatrosses have an elaborate breeding dance that is part of pair-bond formation. Ninety-five percent of seabirds are colonial, and seabird colonies are among the largest bird colonies in the world, providing one of Earth's great wildlife spectacles. Colonies of over

16240-653: The sea at all, spending their lives on lakes, rivers, swamps and, in the case of some of the gulls, cities and agricultural land. In these cases, it is thought that these terrestrial or freshwater birds evolved from marine ancestors. Some seabirds, principally those that nest in tundra , as skuas and phalaropes do, will migrate over land as well. The more marine species, such as petrels, auks and gannets , are more restricted in their habits, but are occasionally seen inland as vagrants. This most commonly happens to young inexperienced birds, but can happen in great numbers to exhausted adults after large storms , an event known as

16380-501: The sea's edge (coast), but are also not treated as seabirds. Sea eagles and other fish-eating birds of prey are also typically excluded, however tied to marine environments they may be. German ornithologist Gerald Mayr defined the "core waterbird" clade Aequornithes in 2010. This lineage gives rise to the Gaviiformes , Sphenisciformes , Procellariiformes, Ciconiiformes , Suliformes and Pelecaniformes . The tropicbirds are part of

16520-407: The sea. Wing morphology has been shaped by the niche an individual species or family has evolved , so that looking at a wing's shape and loading can tell a scientist about its life feeding behaviour. Longer wings and low wing loading are typical of more pelagic species, while diving species have shorter wings. Species such as the wandering albatross , which forage over huge areas of sea, have

16660-416: The skewed sex ratio of western gulls in southern California. Oil spills are also a threat to seabirds: the oil is toxic, and bird feathers become saturated by the oil, causing them to lose their waterproofing. Oil pollution in particular threatens species with restricted ranges or already depressed populations. Climate change mainly affect seabirds via changes to their habitat : various processes in

16800-432: The skills of plunge-diving take several years to fully develop—once mature, they can dive from 20 m (66 ft) above the water's surface, shifting the body before impact to avoid injury. It may be that plunge divers are restricted in their hunting grounds to clear waters that afford a view of their prey from the air. While they are the dominant guild in the tropics, the link between plunge diving and water clarity

16940-457: The sky-call). Each particular pair will develop their own individual version of the dance. The breeding behaviour of other procellariiforms is less elaborate, although similar bonding behaviours are involved, particularly for surface-nesting species. These can involve synchronised flights, mutual preening and calling . Calls are important for helping birds locate potential mates and distinguishing between species, and may also help individuals assess

17080-489: The spread of the northern fulmar through the United Kingdom is attributed in part to the availability of discards. Discards generally benefit surface feeders, such as gannets and petrels, to the detriment of pursuit divers like penguins and guillemots, which can get entangled in the nets. Fisheries also have negative effects on seabirds, and these effects, particularly on the long-lived and slow-breeding albatrosses, are

17220-695: The squid eaten are too large to have been caught alive, and include mid-water species likely to be beyond the reach of albatrosses. Some species will also feed on other seabirds; for example, gulls, skuas and pelicans will often take eggs, chicks and even small adult seabirds from nesting colonies, while the giant petrels can kill prey up to the size of small penguins and seal pups. Seabirds' life histories are dramatically different from those of land birds. In general, they are K-selected , live much longer (anywhere between twenty and sixty years), delay breeding for longer (for up to ten years), and invest more effort into fewer young. Most species will only have one clutch

17360-468: The storm petrels, which are considered to warn of oncoming storms. In general, petrels were considered to be "soul birds", representing the souls of drowned sailors, and it was considered unlucky to touch them. In the Russian language, many petrel species from the Hydrobatidae and Procellariidae families of the order Procellariiformes are known as burevestnik , which literally means 'the announcer of

17500-426: The storm'. When in 1901, the Russian writer Maxim Gorky turned to the imagery of subantarctic avifauna to describe Russian society's attitudes to the coming revolution , he used a storm-announcing petrel as the lead character of a poem that soon became popular in the revolutionary circles as "the battle anthem of the revolution". Although the species called " stormy petrel " in English is not one of those to which

17640-450: The stormy petrel , a very small procellariiform, the egg can be 29 percent of the body weight of the female, while in the grey-faced petrel, the female may spend as much as 80 days feeding out at sea after courtship before laying the egg. When the female returns and lays, incubation is shared between the sexes, with the male taking the first incubation stint and the female returning to sea. The duration of individual stints varies from just

17780-408: The surface of the water, as well as small crustaceans and fish. Petrels obtain food by snatching prey while swimming on the surface, snatching prey from the wing or diving down under the water to pursue prey. Dipping down from flight is most commonly used by the gadfly petrels and the storm petrels . There have been records of wedge-tailed shearwaters snatching flying fish from the air, but as

17920-495: The theme. Many seabirds feed on the ocean's surface, as the action of marine currents often concentrates food such as krill , forage fish , squid , or other prey items within reach of a dipped head. Surface feeding itself can be broken up into two different approaches, surface feeding while flying (for example as practiced by gadfly petrels , frigatebirds , and storm petrels ), and surface feeding while swimming (examples of which are practiced by gulls , fulmars , many of

18060-491: The three species ( Red and Red-necked ) are oceanic for nine months of the year, crossing the equator to feed pelagically. Loons and grebes , which nest on lakes but winter at sea, are usually categorized as water birds, not seabirds. Although there are a number of sea ducks in the family Anatidae that are truly marine in the winter, by convention they are usually excluded from the seabird grouping. Many waders (or shorebirds) and herons are also highly marine, living on

18200-508: The time between feedings is long due to the distance from the nest site that adults forage, thus a chick that had a higher growth rate would stand a better chance of starving to death. The duration between feedings vary among species and during the stages of development. Small feeds are frequent during the guard phase, but afterward become less frequent. However, each feed can deliver a large amount of energy; both sooty shearwater and mottled petrel chicks have been recorded to double their weight in

18340-499: The tropicbirds and some penguins), but most of the colour in seabirds appears in the bills and legs. The plumage of seabirds is thought in many cases to be for camouflage , both defensive (the colour of US Navy battleships is the same as that of Antarctic prions , and in both cases it reduces visibility at sea) and aggressive (the white underside possessed by many seabirds helps hide them from prey below). The usually black wing tips help prevent wear, as they contain melanins that help

18480-574: The two albatross species found in Hawaii, the black-footed albatross takes mostly fish, while the Laysan feeds mainly on squid. The albatrosses in general feed on fish, squid and krill. Among the procellariids, the prions concentrate on small crustacea, the fulmarine petrels take fish and krill but little squid, while the Procellaria petrels consume mainly squid. The storm petrels take small droplets of oil from

18620-505: The very large wandering albatross , at 11 kg (24 lb) and a 3.6-metre (12-foot) wingspan, to tiny birds like the least storm petrel , at 20 g (0.71 oz) with a 32-centimetre (13-inch) wingspan, and the smallest of the prions, the fairy prion , with a wingspan of 23 to 28 cm (9.1 to 11.0 in). Their nostrils are enclosed in one or two tubes on their straight deeply-grooved bills with hooked tips. The beaks are made up of several plates. Their wings are long and narrow;

18760-401: The water, and remaining stationary by hovering with rapid fluttering or by using the wind to anchor themselves in place. A similar flight method is thought to have been used by the extinct petrel family Diomedeoididae . The white-faced storm petrel possesses a unique variation on pattering: holding its wings motionless and at an angle into the wind, it pushes itself off the water's surface in

18900-481: The widely spaced colonies of the giant petrels to the dense 3.6 million-strong colonies of Leach's storm petrels . For almost all species the need to breed is the only reason that procellariiforms return to land at all. Some of the larger petrels have to nest on windswept locations as they require wind to take off and forage for food. Within the colonies, pairs defend usually small territories (the giant petrels and some albatrosses can have very large territories) which

19040-399: The winter. In the tropics, some species can be found breeding throughout the year, but most nest in discreet periods. Procellariiforms return to nesting colonies as much as several months before laying, and attend their nest sites regularly before copulation. Prior to laying, females embark on a lengthy pre-laying exodus to build up energy reserves in order to lay the exceptionally large egg. In

19180-584: Was 22 metres (72 ft); another study, this time on Cory's shearwaters nesting near Corsica , found that of nine out of 61 male chicks that returned to breed at their natal colony bred in the burrow they were raised in, and two actually bred with their own mother. Colonies are usually situated on islands, cliffs or headlands, which land mammals have difficulty accessing. This is thought to provide protection to seabirds, which are often very clumsy on land. Coloniality often arises in types of bird that do not defend feeding territories (such as swifts , which have

19320-653: Was convinced of the need to declare Pelican Island in Florida a National Wildlife Refuge to protect the bird colonies (including the nesting brown pelicans ), and in 1909 he protected the Farallon Islands. Today many important seabird colonies are given some measure of protection, from Heron Island in Australia to Triangle Island in British Columbia. Island restoration techniques, pioneered by New Zealand, enable

19460-504: Was implicated in the extinction of the Guadalupe storm petrel. Already in 1910 Godman wrote: Owing to the introduction of the mongoose and other small carnivorous mammals into their breeding haunts, some species, such as Oestrelata jamaicensis and newelli , have already been completely exterminated, and others appear to be in danger of extinction. Introduced herbivores may unbalance the ecology of islands; introduced rabbits destroyed

19600-477: Was named Procellariiformes by German anatomist Max Fürbringer in 1888. The word comes from the Latin word procella , which means a violent wind or a storm , and -iformes for order . Until the beginning of the 20th century, the family Hydrobatidae was named Procellariidae, and the family now called Procellariidae was rendered "Puffinidae." The order itself was called Tubinares. A major early work on this group

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