The diving petrels form a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
, ''Pelecanoides'', of
seabird
Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same enviro ...
s in the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Procellariidae
The family Procellariidae is a group of seabirds that comprises the fulmarine petrels, the gadfly petrels, the diving petrels, the prions, and the shearwaters. This family is part of the bird order Procellariiformes (or tubenoses), which also ...
. There are four very similar species of diving petrels, distinguished only by small differences in the coloration of their
plumage
Plumage ( "feather") is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, ...
, habitat, and
bill
Bill(s) may refer to:
Common meanings
* Banknote, paper cash (especially in the United States)
* Bill (law), a proposed law put before a legislature
* Invoice, commercial document issued by a seller to a buyer
* Bill, a bird or animal's beak
Plac ...
construction. They are only found in the southern hemisphere. The diving petrels were formerly placed in their own family, the Pelecanoididae.
Diving petrels are auk-like small
petrel
Petrels are tube-nosed seabirds in the bird order Procellariiformes.
Description
The common name does not indicate relationship beyond that point, as "petrels" occur in three of the four families within that group (all except the albatross f ...
s of the southern oceans. The resemblances with the
auk
An auk or alcid is a bird of the family Alcidae in the order Charadriiformes. The alcid family includes the murres, guillemots, auklets, puffins, and murrelets. The word "auk" is derived from Icelandic ''álka'', from Old Norse ''alka'' (a ...
s are due to
convergent evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last com ...
, since both
families
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideall ...
feed by pursuit diving, although some researchers have in the past suggested that the similarities are due to relatedness. Among the Procellariiformes the diving petrels are the family most adapted to life in the sea rather than flying over it, and are generally found closer inshore than other families in the order.
Taxonomy
The genus ''Pelecanoides'' was introduced in 1799 by the French naturalist
Bernard Germain de Lacépède
Bernard-Germain-Étienne de La Ville-sur-Illon, comte de Lacépède or La Cépède (; 26 December 17566 October 1825) was a French naturalist and an active freemason. He is known for his contribution to the Comte de Buffon's great work, the ...
for the
common diving petrel
The common diving petrel (''Pelecanoides urinatrix''), also known as the smaller diving petrel or simply the diving petrel, is a diving petrel, one of four very similar auk-like small petrels of the southern oceans. It is native to South Atlant ...
.
The genus name combines the
Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
''pelekan '' meaning "pelican" and "-oidēs" meaning "resembling".
The diving petrels were formerly placed in their own
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
, Pelecanoididae.
[ When genetic studies found that they were embedded within the family Procellariidae, the family Pelecanoididae were merged into Procellariidae.]
Extant Species
Four species are usually recognised:
A fifth species, the Whenua Hou diving-petrel (''Pelecanoides whenuahouensis''), is sometimes recognised. It was first described in 2018 and is found around Codfish
Cod is the common name for the demersal fish genus '' Gadus'', belonging to the family Gadidae. Cod is also used as part of the common name for a number of other fish species, and one species that belongs to genus ''Gadus'' is commonly not call ...
, or Whenua Hou Island, New Zealand. In the bird list maintained by Frank Gill Frank Gill may refer to:
* Frank Gill (Australian footballer) (1908–1970), Australian rules footballer with Carlton
* Frank Gill (footballer, born 1948), footballer for Tranmere Rovers
*Frank Gill (politician) (1917–1982), New Zealand politicia ...
, Pamela Rasmussen
Pamela Cecile Rasmussen (born October 16, 1959) is an American ornithologist and expert on Asian birds. She was formerly a research associate at the Smithsonian Institution in Washington, D.C., and is based at the Michigan State University. She ...
and David Donsker on behalf of the International Ornithological Committee
The International Ornithologists' Union, formerly known as the International Ornithological Committee, is a group of about 200 international ornithologists, and is responsible for the International Ornithological Congress and other international ...
the Whenua Hou diving-petrel is treated as a subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
of the South Georgia diving petrel.[
The ]evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
and systematics of these birds is not well researched. Several populations were described as distinct species and while most of them are only subspecies, some may indeed be distinct. The prehistoric fossil record
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...
was long limited to very fragmentary remains described as ''P. cymatotrypetes'' found in Early Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58[Langebaanweg
Langebaanweg is a town on the southwest coast of South Africa, in Western Cape Province.
It is the location of the air force base AFB Langebaanweg.
Langebaanweg has been an important mining center, with its mai minerals consisting of phosphorite ...](_blank)
, South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
; while this bird apparently was close to the common diving petrel, no members of the genus are known from South African waters today.
In 2007, a humerus
The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...
piece from New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
was described as '' P. miokuaka''. This was found in Early/Middle Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
deposits and just as may be expected, it far more resembles diving petrels than any other known bird, but presents a less apomorph
In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have ...
ic condition.
Description
The diving petrels are small petrels that measure between and weigh . They are highly uniform in appearance, and very difficult to distinguish when seen at sea. They are best distinguished by the size and shape of their short bills. The plumage
Plumage ( "feather") is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, ...
is shining black on the top and white on the underside. Their wings are short, particularly with regards to overall body size, and used in a highly characteristic whirring flight. This flight is low over the water and diving petrels will fly through the crests of waves without any interruption of their flight path. In the water these wings are half folded and used as paddles to propel the bird after its prey
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...
.
Behaviour
Food and feeding
Diving petrels are plankton
Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...
feeders, taking mostly crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...
prey such as krill
Krill are small crustaceans of the order Euphausiacea, and are found in all the world's oceans. The name "krill" comes from the Norwegian
Norwegian, Norwayan, or Norsk may refer to:
*Something of, from, or related to Norway, a country in n ...
, copepod
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (inhabiting sea waters), some are benthos, benthic (living on the ocean floor) ...
s and the amphipod
Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far descr ...
''Themisto gaudichaudii
''Themisto gaudichaudii'' is an amphipod crustacean of the suborder Hyperiidea.
Relatives
The 260 species of hyperiid amphipods are large-eyed and planktonic amphipods, whereas gammarid amphipods have smaller eyes and tend to live on the sea fl ...
'', also taking small fish and squid
True squid are molluscs with an elongated soft body, large eyes, eight arms, and two tentacles in the superorder Decapodiformes, though many other molluscs within the broader Neocoleoidea are also called squid despite not strictly fitting t ...
. They have several adaptations for obtaining their prey including short powerful wings, a gular pouch
Gular skin (throat skin), in ornithology, is an area of featherless skin on birds that joins the lower mandible of the beak (or ''bill'') to the bird's neck. Other vertebrate taxa may have a comparable anatomical structure that is referred to as e ...
for storing food, and their nostril
A nostril (or naris , plural ''nares'' ) is either of the two orifices of the nose. They enable the entry and exit of air and other gasses through the nasal cavities. In birds and mammals, they contain branched bones or cartilages called turbi ...
s open upwards rather than pointing forward as in other tubenoses.
Breeding
These bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
s nest in colonies on islands. One white egg
An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the a ...
is laid in a burrow in turf or soft soil that is usually covered with vegetation, feather
Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and a premier ...
s, or small rocks. They are nocturnal at the breeding colonies. It has a long period of parental care (around 45 to 60 days) in the burrow, but once the chick fledge
Fledging is the stage in a flying animal's life between hatching or birth and becoming capable of flight.
This term is most frequently applied to birds, but is also used for bats. For altricial birds, those that spend more time in vulnerable c ...
s out to sea it is on its own.
Status and conservation
Of the four species, two, the Peruvian diving petrel
The Peruvian diving petrel (''Pelecanoides garnotii'') (local name in Peru: potoyunco) is a small seabird that feeds in offshore waters in the Humboldt Current off Peru and Chile.
Taxonomy
The Peruvian diving petrel was formally described in 18 ...
and the Magellanic diving petrel
The Magellanic diving-petrel (''Pelecanoides magellani'') is a species of diving petrel, one of five very similar, small, auk-like petrels found exclusively in the southern oceans. It is one of the smaller species of diving-petrels, though size d ...
, have highly restricted ranges around South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
's coasts, while the common diving petrel
The common diving petrel (''Pelecanoides urinatrix''), also known as the smaller diving petrel or simply the diving petrel, is a diving petrel, one of four very similar auk-like small petrels of the southern oceans. It is native to South Atlant ...
and the South Georgia diving petrel
The South Georgia diving petrel or Georgian diving-petrel (''Pelecanoides georgicus'') is one of five very similar small auk-like diving petrels of the southern oceans. It is native to the South Atlantic and islands of the southern Indian Ocean a ...
range widely across the southern oceans, breeding on islands off New Zealand, Subantarctic
The sub-Antarctic zone is a region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region includes many islands ...
islands in the Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...
, and islands in the south Atlantic
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...
(like Tristan da Cunha
Tristan da Cunha (), colloquially Tristan, is a remote group of volcanic islands in the South Atlantic Ocean. It is the most remote inhabited archipelago in the world, lying approximately from Cape Town in South Africa, from Saint Helena ...
). The subspecies, the Whenua Hou diving petrel
The Whenua Hou diving-petrel (''Pelecanoides georgicus whenuahouensis'') is a highly endangered subspecies of the South Georgia diving petrel that is endemic to New Zealand.
The subspecies was first described by Johannes H. Fischer and collab ...
, has an extremely restricted range, breeding only on New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
's Codfish Island
Codfish Island / Whenua Hou is a small island () located to the west of Stewart Island in southern New Zealand. It reaches a height of close to the south coast. The island is home to Sirocco, an internationally famous kākāpō, a rare speci ...
.[
Diving petrels are among the world's most numerous birds, with common and South Georgia diving petrels numbering several million pairs each. The Peruvian and Whenua Hou diving petrels, on the other hand, are highly threatened by ]guano
Guano (Spanish from qu, wanu) is the accumulated excrement of seabirds or bats. As a manure, guano is a highly effective fertilizer due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. G ...
extraction, introduced species
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there ...
and climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...
, and are considered endangered species
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...
.
References
{{Taxonbar, from=Q539433
Diving animals
Extant Miocene first appearances
*