''Calonectris'' is a genus of

seabird Seabirds (also known as marine birds) are birds that are adaptation, adapted to life within the marine ecosystem, marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent ...

s. The

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

name comes from

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

''kalos'', "good" and ''nectris'', "swimmer". The genus comprises four large

shearwater Shearwaters are medium-sized long-winged seabirds in the petrel family Procellariidae. They have a global marine distribution, but are most common in temperate and cold waters, and are pelagic outside the breeding season. Description These tube ...

s. There are two other shearwater genera, ''

Puffinus ''Puffinus'' is a genus of seabirds in the order Procellariiformes that contains about 20 small to medium-sized shearwaters. Two other shearwater genera are named: '' Calonectris'', which comprises three or four large shearwaters, and '' Ardenna ...

'', which comprises 21 small to medium-sized shearwaters, and '' Ardenna'' with 7 larger species. The

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

in this group are long-winged birds, dark brown or grey-brown above, and mainly white below. They are pelagic outside the breeding season. They are most common in temperate and cold waters. Like most other tubenose birds, they use a shearing flight technique to move across wave fronts with the minimum of active flight, but fly with a more relaxed, fluid, flexible wing action than the other shearwaters in ''Puffinus'' and ''Ardenna''. Svensson, L., Mullarney, K., & Zetterström, D. (2022) '' Collins Bird Guide'', ed. 3. , pages 68-69 ''Calonectris'' shearwaters are long-distance migrants. The streaked shearwater disperses from its east

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

n breeding islands throughout the western

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the cont ...

and into the eastern

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

. They come to islands and coastal cliffs only to breed. They are nocturnal at the colonial breeding sites, preferring moonless nights to minimise predation. They nest in burrows and often give eerie contact calls on their night time visits. They lay a single 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 ...

. They feed on fish, squid and similar oceanic food. They will follow fishing boats to take scraps.

Taxonomy

The genus ''Calonectris'' was introduced in 1915 by the ornithologists Gregory Mathews and

Tom Iredale Tom Iredale (24 March 1880 – 12 April 1972) was an English-born ornithologist and malacologist who had a long association with Australia, where he lived for most of his life. He was an Autodidacticism, autodidact who never went to university ...

with the

streaked shearwater The streaked shearwater (''Calonectris leucomelas'') is a species of seabird. The adult bird averages in length, with a wingspan. Description The streaked shearwater feeds mainly on fish and squid. It follows fishing boats, attracted to anch ...

as the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

. The genus name combines the

''kalos'' meaning "good" or "noble" with the genus name ''Nectris'' that was used for shearwaters by the German naturalist

Heinrich Kuhl Heinrich Kuhl (17 September 1797 – 14 September 1821) was a German people, German naturalist and zoologist. Kuhl was born in Hanau (Hesse, Germany). Between 1817 and 1820, he was the assistant of professor Th. van Swinderen, docent of natural ...

in 1820. The name ''Nectris'' comes from the Ancient Greek ''nēktris'' meaning "swimmer". Scopoli's shearwater and Cory's shearwater were previously considered as conspecific and formed the Cory's shearwater complex (''Calonectris diomedea''). Based on the lack of hybridization and differences in mitochondrial DNA, morphology and vocalisation, the complex was split into two separate species. The English name "Cory's shearwater" was transferred to ''Calonectris borealis'' while what was previously the

nominate subspecies In biological classification, subspecies (: 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. ...

became Scopoli's shearwater (''Calonectris diomedea'').

Species

The genus contains four species. Extinct species, '' Calonectris krantzi'' from the

Early Pliocene Early may refer to: Places in the United States * Early, Iowa, a city * Early, Texas, a city * Early Branch, a stream in Missouri * Early County, Georgia * Fort Early, Georgia, an early 19th century fort Music * Early B, stage name of Jamaican d ...

and '' Calonectris wingatei'' from the

Middle Pleistocene The Chibanian, more widely known as the Middle Pleistocene (its previous informal name), is an Age (geology), age in the international geologic timescale or a Stage (stratigraphy), stage in chronostratigraphy, being a division of the Pleistocen ...

, have also been described from

fossil 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 preserve ...

s. ''Calonectris kurodai'', another fossil from the Middle Miocene Calvert Formation of Chesapeake Bay is named after the Japanese ornithologist Nagahisa Kuroda.

Phylogeny

Phylogeny based on a study by Joan Ferrer Obiol and collaborators published in 2022.

Taxonomy

Species

Phylogeny

References

Further reading